Stamcel transplantatie bij Li-Fraumeni een goed idee?



TP53 Testing and Li-Fraumeni Syndrome: Current Status of Clinical Applications and Future Directions


Prevalent as an acquired abnormality in cancer, the role of TP53 as a germline mutation continues to evolve. The clinical impact of a germline TP53 mutation is often dramatic and affects the full life course, with a propensity to develop rare tumors in childhood and multiple common cancers of unexpectedly early onset in adulthood. We review the clinical relevance of germline mutations in the TP53 tumor suppressor gene in current healthcare practices, including the optimal ways to identify patients with Li-Fraumeni syndrome (LFS), to recognize the core-cancers associated with LFS and to develop strategies for early detection of LFS-associated tumors. Several TP53-targeted approaches to improve outcomes in LFS patients are also reviewed. A case report was used to highlight special TP53 testing dilemmas and unique challenges associated with genetic testing decisions in our current age of rapidly advancing genomic technologies.

Keywords: TP53, Li-Fraumeni syndrome, genetic testing, cancer risk, genetic counseling

1. Introduction

Li-Fraumeni syndrome (LFS; OMIM 151623) is an autosomal dominant cancer syndrome caused by heterozygous germline mutations in the TP53 gene. Half of patients with LFS develop at least one LFS-associated cancer by age 30.

[14] This is in comparison to the 1% chance of developing cancer by age 30 in the general population.[5] Almost one third (15-35%) of cancer survivors with LFS will develop multiple primary cancers over their lifetimes.[69] LFS predisposes to radiation-induced malignancies as well.[1012]Understanding the critical role of TP53 as the guardian of the genome has long suggested the potential for targeted cancer treatment.

In this review, we will discuss the clinical relevance of TP53 mutations to modern day healthcare practices. We will review the literature on the clinical picture of LFS, genetic testing criteria, issues related to genetic testing for LFS, and management recommendations. We will also review emerging methods for early disease detection and promising TP53 -targeted approaches to maximize outcomes.

2. Historical Milestones

As we rise to the challenge of merging the explosive number of key findings in the field of cancer biology, it is appropriate to review the medical impact of a gene that has revolutionized the field of cancer biology–TP53.

TP53 was first discovered in 1979[1315] during a period of time when the viral theory of cancer development was held in highest esteem. The viral theory suggested that viruses (such as the Simian virus 40, human papilloma virus, and Epstein Barr virus) were the principal drivers of oncogenesis. The identification and characterization of TP53 changed this theoretical paradigm, leading us into the current age of genomics and advancing our understanding of the role that oncogenes and tumor suppressor genes play in malignant transformation.[1619]

Because of TP53’s key role as the “guardian of the genome,”[20] more than half of all human cancers acquire mechanisms to impede TP53 function. TP53 is the most frequently mutated gene in human cancer[19] with the prevalence of acquired TP53 mutations highest in epithelial ovarian cancers (47%), colorectal (43%), head/neck (42%), and esophageal cancers (41%) (International Agency for Research on Cancer (IARC) database, R15 release).[21] Cancers with acquired TP53 mutations are also associated with diminished survival rates, increased resistance to chemotherapy and radiation, and elevated relapse rates.[2224]

TP53 was first detected in simian virus 40-transformed cells[14, 25] with high levels of detectable p53 protein also seen in cells transformed by other biological or physical agents[26, 27] in tumor cell lines[28] and in human cancers (especially leukemia and sarcoma).[2933]

In 1989, Lavigueur and colleagues accelerated TP53 research when they reported that 20% of transgenic mice carrying a germline mutant TP53 gene developed lung adenocarcinomas, osteosarcomas, and lymphomas. They identified variable degrees of disease penetration and the occasional occurrence of simultaneous primary cancers; and the rare development of cancers like rhabdomyosarcoma, skin carcinoma, fibrosarcoma, testicular carcinoma, and adrenal neuroblastoma.[34]

In 1996, Pfeifer et al. showed that TP53 pathway alterations could directly cause human cancer. Using the active metabolite of benzo[a]pyrene (a byproduct of cigarette smoke), Pfeifer’s group induced TP53mutagenesis, causing malignant transformation with unique genetic alterations.[35, 36] Pfeifer’s work refuted tobacco industry claims by providing the “smoking gun,” scientific proof that cigarettes caused human lung cancer and was, therefore, the lynchpin research that changed public health policies and practices in the United States and abroad.[35, 37] During a similar timeframe, Donehower and colleagues showed that TP53did not appear to impair normal embryogenesis, growth, or development in genetically engineered mice.[3840] Donehower’s observations confirmed that germline mutations in the TP53 gene could be present without lethal consequences; making an inherited human disorder a plausible concept.[14, 25, 26, 41]

The original suggestion of a familial cancer syndrome of diverse tumors in humans was first proposed in 1969 by two physician-scientists, Drs. Frederick P. Li and Joseph F. Fraumeni, Jr., after identifying aggressive, soft tissue sarcomas in young siblings and their biologically-related cousins.[42] Over a twenty year period, they defined and refined a clinical syndrome that was ultimately confirmed, by segregation analysis, to be of genetic etiology and given the moniker “Li-Fraumeni syndrome” (LFS).[3, 9, 43, 44]Molecular genetic testing for TP53 germline mutations was developed in 1990 by David Malkin and colleagues[45, 46] and was quickly used as a screening tool to identify patients with hereditary forms of cancer.[4749] In the early 1990s, Louis Strong and colleagues were the first to develop cancer-specific risk estimates, improving clinical care for families with LFS.[50] These major landmarks in TP53 history have formed the foundation for the modern era of scientific advancements in TP53 -related research and clinical care.[41]

3. Li-Fraumeni Syndrome Core Cancers

While many tumor types can be seen in patients with LFS, four core cancers (breast, sarcoma, brain, and adrenocortical carcinoma) make up about 80% of LFS associated tumors.[1, 43, 44, 51]

Breast Cancer accounts for about 25-30% of all LFS-associated tumors.[1, 51, 52] This is believed to account for at least part of the difference in lifetime cancer risk between women and men (nearly 100% vs. 73%, respectively).[53] Breast cancer is most predictive of the presence of a germline TP53 mutation when it is diagnosed before age 30-35 in a woman with a family history of a first- or second-degree relative with a core LFS cancer (other than breast cancer).[1, 54, 55] Women with LFS-associated breast cancer tend to present at an earlier age (in the 20s or early 30s) with more advanced stage disease (i.e., tumors greater than 5 cm and axillary node disease) at the time of initial diagnosis. Recent studies have begun to describe the phenotype of breast cancers in TP53 mutation carriers.[5658] All three studies found that the majority of breast tumors were Her2Neu positive, and Melhem-Bertrandt et al. found a significantly greater number of Her2Neu positive tumors among TP53 carriers than among non-carriers (p = 0.0001; table 1).[57] Therefore, the emerging phenotype of a classic LFS-associated breast cancer appears to be ductal in histology, ER, PR, and Her2/neu positive, and diagnosed in the 20s or early 30s.

Table I

Breast Cancer Receptor Phenotype in TP53 Mutation Carriers

Sarcomas (weke delen kanker) account for another 25-30% of all LFS-associated tumors.[1, 51, 59, 60] Multiple types of soft tissue sarcomas and osteosarcoma are associated with LFS; but Ewings sarcoma, gastrointestinal stromal cell tumors (GIST), desmoids tumors, and angiosarcomas have not been reported in LFS.[59] A recent study by Ognjanovic et al. compared sarcomas diagnosed in TP53 mutation carriers in the IARC TP53 database (n=236) to sarcoma diagnoses in the Surveillance, Epidemiology, and End Results (SEER) database (n=34,671).[59] They found that 67% of sarcomas in TP53 mutation carriers occurred before the age of 20 compared with only 11.9% in the SEER database; in TP53 carriers only 4.4% of sarcomas occurred after age 50, while 62.7% were diagnosed after 50 in the SEER data. The age distribution of sarcomas in TP53mutation carriers is biphasic, with one peak in childhood and another between ages 20 and 40.[59, 60]

Brain Tumors occur in 9-16% of individuals with TP53 mutations.[1, 51, 60, 61] Glioblastomas/astrocytomas are the most common but, medulloblastoma, ependymoma, supratentorial primitive neuroectodermal tumors, and choroid plexus tumors may also be seen.[61, 62] Despite limited sample sizes, a compelling body of evidence supports the association between choroid plexus tumors, particularly choroid plexus carcinomas (CPC) and TP53 germline mutations.[1, 22, 6365] Gonzalez et al. reported that all 8 individuals in their cohort with choroid plexus tumor (type not specified) and no additional personal or family history reported were positive for a germline TP53 mutation.[1] Other studies report prevalence rates between 36-44% in patients with choroid plexus carcinomas, many of whom also met the Classic LFS or Li-Fraumeni-Like (LFL) criteria.[22, 65] As with sarcoma, there appears to be a biphasic age distribution of brain tumors in those withTP53 mutations, with highest prevalence rates before age 10 and after 20 years of age.[51, 60]

Adrenocortical Carcinoma bijnierschors (ACC) accounts for 10-14% of cancers in TP53 mutation carriers overall.[1, 60]While ACC has been diagnosed in individuals with LFS at a wide range of ages, it is considered a hallmark of LFS when diagnosed in childhood.[1, 60, 66] The IARC TP53 database reports a median age of ACC diagnosis among TP53 mutation carriers of 4.8 years versus 41.9 years among sporadic cases of ACC.[60]Gonzalez et al. found that 80% of individuals in their cohort with ACC diagnosed under 18 had TP53mutations.[1] The highest prevalence rates of ACC are reported in carriers of the Brazilian founder mutation,TP53 R337H. The R337H mutation is present at a high frequency in southern Brazil (about 1 in 300 individuals)[67, 68] and evidence shows it to be a founder mutation.[52, 69] The frequency of this mutation among children with ACC in southern Brazil is 78-97%.[70, 71] Initially, it was thought to be a low penetrance mutation that predisposes only to ACC and not other LFS-associated tumors.[7072] However, more recent studies have found that the R337H mutation can be found in families with a broad spectrum of LFS-associated cancers.[73, 74]

(opmerking tvdwal: opver R337H , niet bekend hoe dat zit bij Nederlandse dragers?)

Other LFS Cancers

Beyond the four core LFS cancers, the next most frequently associated cancers include:

.[1, 51, 60, 7577] All cancer types are diagnosed at younger than average ages. One study on colorectal cancer in LFS families found the average age of diagnosis to be 33, with four individuals diagnosed before age 21.[75] A study of gastric cancer in LFS families found an average age of diagnosis of 43 (range: 24-74), with four diagnosed before age 30.[75, 76]

4. TP53 Gene and Genotype-Phenotype Correlations

The human TP53 gene (chromosome 17p13.1) encodes for a ubiquitous transcription factor that is now known to be responsible for a complex set of critical regulatory functions that promote DNA repair and tumor suppression. It contains 11 exons (including 10 coding exons) and encodes for a protein that is 393 amino acids long. The TP53 gene is comprised of four distinct types of functional domains: two transactivation domains (amino acids 1-42 and 43-62), a centralized DNA binding and mutation hotspot domain (102-292), an oligomerization domain (323-356), and a regulatory domain (363-393) (figure 1).[49,78] Most TP53 mutations are clustered in the DNA-binding domain within specific codons, such as 175 and 248 (figure 2). TP53 mutations are often missense alterations[21] that cause a change in one nucleotide and encode for a different amino acid than the one typically found in that particular location within the protein. Missense mutations are usually transcriptionally inactive; however, some reports have shown gain of function oncogenic effects in TP53.[79, 80]

Fig. 1

A graphic representation of the TP53 gene (boxes) and protein (cylinders), adapted from the IARC TP53 database.[21] The TP53 gene contains 11 exons represented by the numbered boxes. The exons 2-4 (yellow) encode for the two Transactivation domains (I,

Fig. 2

Summary of the most frequent TP53 germline mutations by codon, reproduced from the International Agency for research on Cancer (IARC) TP53 database.[21] Each vertical line represents the codon location of a TP53 germline mutation. The codon location for

Genotype-phenotype correlations in LFS are predictive of age of tumor onset, highest tumor risks, and outcome in patients with TP53 germline mutations.[51, 59, 60, 81] Mutations in the DNA binding portion of the gene cause highly penetrant disease with very early onset cancers; mutations outside the core DNA binding domain are associated with slower rates of tumor development.[8284] Monti and colleagues utilized clinically-annotated TP53 mutation data contained in the IARC database to correlate the functional properties of 104 TP53 germline mutations (with single amino acid substitutions) to cancer-related outcomes. They (and others) have used yeast-based functional assays to show that TP53 mutant alleles with reduced transactivation capability (including dominant negative acting proteins that reduce the transactivation ability of the p53 wild-type protein) are associated with a higher frequency of multiple tumors and are more likely to be found in germline carriers with strong family histories of cancer.[85] Inherited genetic variations (including single-nucleotide polymorphisms, SNPs) of the TP53 gene have been reported to impair p53 function in vitro and are associated with worse outcomes in specific subgroups of patients with cancer.[86]

5. Li-Fraumeni Syndrome: Genetic Testing

The diagnosis of LFS is based on an evolving set of clinical classification criteria that have been established using the most salient aspects of family history and tumor-related characteristics. Deleterious (disease causing) mutations in TP53 are only found in ~70% of the patients who meet the classic diagnostic criteria for LFS,[43] underscoring the importance of clinical suspicion and astute diagnostic skills when trying to identify affected patients and families. TP53 genotyping is typically performed by DNA Sanger sequence analysis and multiplex ligation-dependant probe assay or other technique to detect large rearrangements of portions of the gene.[87]

5.1. Testing Criteria

The following is a summary of when TP53 analysis may be recommended, and when personal and family history should be evaluated for LFS and TP53 genotyping should be considered. The National Comprehensive Cancer Network (NCCN) guidelines recommend TP53 analysis for individuals who meet either the classic LFS criteria, the Chompret criteria, or who were diagnosed with breast cancer under age 30.[88]

  • Published Criteria Several sets of criteria have been developed over the past 20 years to help identify individuals with LFS who should be considered for TP53 testing (table 2). The first formal set of criteria developed (in 1988) is the Classic LFS criteria; these criteria are the most stringent and are the ones used to make a clinical diagnosis of LFS (with or without the identification of a deleterious germline TP53 mutation).[43] Later, broader criteria were developed by Birch and Eeles to identify families which are Li-Fraumeni-like (LFL).[83, 89] Chompret and colleagues developed another set of criteria which were shown to provide the highest positive predictive value and, when combined with the classic LFS criteria, provided the highest sensitivity for identifying individuals with LFS (table 3).[1, 90] During the 3rd International p53 mutant workshop-LFS symposium in 2007, the Chompret criteria were modified to develop a set of Consensus-based criteria to identify TP53 carriers.[60] The Chompret criteria were most recently updated in 2009 to better identify families with milder phenotypes.[84, 91]

    Table II

    Diagnostic criteria for Li-Fraumeni Syndrome and Li-Fraumeni Like Syndrome and criteria for TP53 genetic testing

    Table III

    Likelihood of detecting a mutation based on current clinical classification schemes
  • Breast Cancer < 30 Some, including the NCCN, advocate testing all individuals with breast cancer under age 30 who are negative for BRCA1 and BRCA2 mutations for TP53 mutations.[1, 55, 61, 88]However, others do not support this recommendation, stating that without additional family history, the probability of mutation is too low (<5%).[91] Most recently, McCuaig et al. have suggested that aTP53 mutation is actually more likely than a BRCA1 or BRCA2 mutation in women with breast cancer diagnosed under age 30 without contributory family history.[92] They, therefore, propose that testing for BRCA1, BRCA2, and TP53 be performed simultaneously in this subset of patients.
  • Adrenocortical Carcinoma Well-established criteria recommend TP53 analysis for any individual with ACC regardless of age at diagnosis or family history.[88, 91] Based on the published literature, however, it appears that the probability of finding a TP53 mutation is higher in ACC diagnosed <40, especially those diagnosed in childhood.[1, 60, 66]
  • Choroid Plexus Carcinoma The 2009 Chompret criteria recommend germline TP53 analysis for any patient with CPT regardless of family history.[1, 91]
  • GI Cancers ( noot: spijsvertering )TP53 mutation analysis should also be considered in cases of early onset gastrointestinal (GI) cancer who meet the classic LFS or LFL criteria if other more common hereditary GI syndromes have been ruled out.[75, 76]

5.2. Other TP53 Genetic Testing Considerations

In an attempt to develop an approach to finding other patients with LFS, Gonzalez and colleagues published the largest single report from a diagnostic testing lab.[1] Using clinical data from a TP53 clinical testing cohort of 525 patients submitted for testing, with 91 mutations identified, prevalence tables summarizing the individual and family characteristics associated with TP53 mutations were created. These tables can be used as clinical tools to help guide testing decisions (table 4). Gonzalez and colleagues found that the highest germline TP53 mutation frequency rate (100%; n=5) was in patients who had at least one core cancer during childhood (prior to 18 years of age) and a positive family history for cancer.

Table IV

Prevalence of TP53 mutations

TP53 testing is generally not recommended without a substantial probability of identifying a deleterious mutation. One of the most common and challenging clinical testing dilemmas is determining the most appropriate testing strategy for a woman who has tested negative for BRCA1 and BRCA2 mutations, but who has a family history consistent with a hereditary breast cancer syndrome. Indeed the NCCN recommendsTP53 genetic testing for patients with breast cancer diagnosed under age 30, who have already tested negative for BRCA1 and BRCA2. However, in the absence of very early age of breast cancer diagnosis, most families with breast cancer have an exceedingly low probability of carrying a TP53 mutation.[91] For example, if there are multiple cases of breast cancer in a family, but there are women interspersed between them who have lived past age 50 and not developed breast cancer, TP53 testing is usually not warranted. Common cancers historically associated with TP53 (such as leukemia and lung cancer), which are not among the more recently reported core Li-Fraumeni-associated cancers,[44] do not add to the likelihood of detecting a mutation.[1] Similarly, sarcoma patients over age 50 are much less common in Li-Fraumeni families than in the general population.[59] However, like all of medicine, there are rare exceptions to these rules, supporting the need for clinical judgment to navigate the nuances of strategizing the gene testing process.

6. Genetic Counseling for Li-Fraumeni Syndrome

6.1. Pre- and Post-Test Counseling

Decisions regarding germline TP53 testing should be made by healthcare professionals with specialized training in clinical cancer genetics and experience interpreting complex, and potentially novel, variant gene mutations of uncertain clinical significance. All patients should have cancer genetic counseling, prior to initiating the testing process, and access to long term counseling to support the educational and psychosocial needs of LFS patients and their families.

6.2. Risk for Family Members

Most TP53 mutations have been inherited from a parent. After identifying a mutation, the proband’s parent with any pertinent cancer history or family history should be tested first to establish the lineage of the mutation; otherwise, both parents should be tested. A family history can appear negative due to a limited family structure or incomplete penetrance of the mutation. The frequency of de novo mutations is not well established; however, based on two studies, the de novo rate has been estimated to be as low as 7% (5 of 75) and as high as 24% (4 of 17).[53, 93]

Siblings and offspring of the proband should also be tested. If one of the proband’s parents carries the TP53mutation, each sibling has a 50% risk of having the mutation. If neither parent is found to carry the mutation, the risk to siblings is low, but they should be tested due to the possibility of germline mosaicism. Offspring of a proband have a 50% risk of carrying the mutation.

6.3. Testing of At-Risk Unaffected Children

For some time, testing of at-risk minors for identified TP53 mutations has been controversial, due to the lack of proven surveillance or prevention strategies and concerns about informed consent, stigmatization, and discrimination.[94] However, due to emerging screening protocols showing efficacy in reducing mortality from TP53-related malignancies,[95] testing of at-risk children is now considered.

6.4. Preimplantation Genetic Diagnosis (PGD)

PGD is available for high-risk couples seeking to avoid an affected pregnancy. PGD uses a standard in-vitro fertilization procedure, allowing embryos to be tested for an identified disease-causing TP53 mutation prior to being transferred to the uterus.[96] PGD for LFS is one of the most compelling uses of this technology, among all cancer-predisposing syndromes, due to the early age of onset of cancer and significant risk of death by early adulthood.[97] PGD for TP53 mutations has been described and successfully performed.[98]Prenatal diagnosis of LFS using amniocentesis or chorionic villus sampling (CVS) is another option for avoiding an affected child. Such an approach has been described but, due to the consideration of termination of an affected pregnancy, is controversial and psychologically difficult for families.[99]

6.5. Psychological Considerations

Psychological functioning in individuals and families considering germline TP53 testing is an understudied but important aspect of clinical decision making and should be addressed throughout the counseling process. Peterson et al studied individual perceptions of cancer risk and psychological distress in 92 members of 15 LFS-families. They found that increased psychological distress was associated with poor quality of life and a higher perceived risk of carrying a TP53 germline mutation. Interestingly, they also found that study participants with no personal history of cancer reported more psychological distress than those personally affected by cancer. Increased distress was also seen in participants who had a larger number of relatives affected by cancer.[100] Another study of 119 individuals considering TP53 testing found that study participants who lacked social support were more prone to report clinically relevant levels of distress.[101]TP53 germline carriers did not show higher levels of distress than non-carriers or those who declined testing. A substantial proportion of the overall group (23%) reported clinically relevant levels of distress.[101]Partners of patients with a high probability of carrying a TP53 germline mutation have been reported to have elevated levels of distress and have expressed a desire for psychosocial support services.[102] Collectively, these reports support the need for comprehensive counseling services, including psychosocial counseling, for individuals and families considering TP53 germline testing.[100, 101]

6.6. Duty to Warn

When patients are reluctant to share relevant genetic information with family members, physicians may have to consider how to balance the patient’s privacy with the interests of at-risk family members who can benefit from available screening and interventions. However, warning the relatives without the patient’s consent is not consistent with the provider’s ethical obligation to the patient and could be at odds with state and federal privacy laws. Instead, it is appropriate for providers to encourage patients to share such genetic information with relatives in a manner that is deliberate, but not coercive.[103]

6.7. New Challenges to Informed Consent: TP53 Mutation Discovery with Genomic Approaches

With the growing availability and use of whole genome sequencing (WGS), whole exome sequencing (WES), whole genome arrays, and multi-gene panels comes the increased likelihood of unintentionally or unexpectedly identifying a TP53 mutation carrier. There have already been some case reports of this in the literature. One case was discovered through whole genome array CGH done on a child with mental retardation and no family history of cancer.[104] Another case was discovered through WGS performed on a patient with myelodysplastic syndrome and a history of premenopausal breast and ovarian cancer who had normal genotyping for BRCA1 and BRCA2 and no family history suggestive of a hereditary cancer syndrome.[105] These cases bring up important and complicated questions about how to ensure an adequate informed consent process for genomic testing, maintain health information privacy, and provide appropriate mechanisms for test result disclosures.[106108] Employing these molecular strategies especially on a research basis, initially, will help us to gain a broader phenotypic picture of hereditary cancer syndromes like LFS.[77,106, 109]

Whole sequences kan dus interessant zijn !

7. Management of Li-Fraumeni Syndrome Patients

Guidelines for the management of patients with LFS have been published by the NCCN and include the following recommendations for early detection of disease: (1) children and adults should undergo comprehensive annual physical examination; (2) women should undergo age-specific breast cancer monitoring that is routine for women with an increased inherited risk which includes annual mammograms, breast MRI,[110] and clinical breast examination beginning at age 20-25 years, or even earlier based on the youngest age of onset in the family, and consider the option of risk-reducing mastectomy; and (3) all should see a physician promptly for evaluation of lingering symptoms and illnesses.[88]

Due to the challenges of interpreting results of mammographic images of dense breast tissue in young women and the need to reduce lifetime exposure to radiation, the ACS recommends delaying the use of yearly mammograms in women with LFS until after 25-30 years of age.[111] The NCCN also indicates that MRI-only screening may be sufficient between ages 20 and 30.[88] The NCCN prevention guidelines also include recommendations that adults can consider colonoscopy every 2-5 years beginning no later than age 25, that individuals should undergo organ-targeted surveillance based on the pattern of cancer observed in the family, and that the option to participate in novel screening approaches (such as total body MRI and brain MRI, see below) should be discussed.[88]

7.1. Enhanced Surveillance

Historically, enhanced surveillance for early disease detection in LFS patients beyond what is recommended in the NCCN guidelines has been considered investigational, primarily due to a lack of a proven survival benefit.[112, 113] However, recent reports show that enhanced screening protocols can detect early stage disease and improve outcome in LFS patients.[95, 113, 114]

The first successful LFS-screening study incorporated PET-CT (F18-Fluorodeoxyglucose–Positron Emission Tomography/Computed Tomography) imaging into an enhanced clinical surveillance regimen. The PET-CT study, conducted by Masciari et al, successfully identified cancer in 20% (n=3) of the 15 asymptomatic LFS individuals studied.[113] Two LFS patients had papillary thyroid cancer (stage II and stage III); one LFS patient had stage II esophageal adenocarcinoma. This study laid the foundation for a subsequent study by Villani et al., wherein there was an effort to minimize screening-associated ionizing radiation exposure.

Villani and colleagues conducted a prospective, observational study of eight LFS families.[95] The thirty-three asymptomatic germline TP53 mutation carriers studied self-selected to be followed with enhanced surveillance (n=18) or routine institutional follow-up care (n=16; one LFS patient was in both groups). The surveillance protocol is published and included physical examinations with targeted biochemical monitoring and radiological imaging (with ultrasounds, brain MRIs, and rapid total body MRI scans).[95] The overall survival at 3 years was excellent (100%) in the surveillance group, but only 21% in the group without enhanced surveillance (95% CI 4-48%; p=0.0155). Ten tumors were identified in 7 members of the surveillance group; the five cancers detected were choroid plexus carcinomas (n=2), Adrenocortical carcinomas (n=2), and one malignant fibrous histiocytoma. Three low grade gliomas and one case of myelodysplastic syndrome were also detected in this group.[95]

This is the first reported data that clearly shows a survival benefit for enhanced surveillance in LFS patients. Due to the rarity of LFS, it is not realistically feasible to conduct outcome studies using large scale, randomized, clinical trial study designs. It is, however, reasonable to utilize well developed prospective studies, such as the one conducted by Villani et al., to inform decisions about advanced clinical care options for LFS patients.

Current biochemical screening tests for LFS-patients include standardized tumor-based assays, such as 17-Hydroxyprogesterone to help detect adenocortical carcinoma. However, several research-based testing methodologies are beginning to show promise as future tools for early disease detection and risk stratification for LFS patients. For instance, genomic assessment of copy number variation (CNV) can yield a pattern associated with LFS-associated cancers compared to other cancers and may identify early stage disease in asymptomatic germline TP53 mutation carriers.[115] In one study, germline TP53 mutation carriers had a 4-8 fold increase in CNV, and affected TP53 carriers had much higher CNV levels than unaffected carriers.[115]Recently, LFS has been associated with shortened telomere length.[116, 117] Telomere length may be a reliable marker for assessing cancer-risk and for determining the most appropriate timeframe to begin enhanced surveillance regimens for LFS carriers.

7.2. Other Considerations in Breast Cancer Risk-Reduction and Screening

As part of individualized preventative care, risk-reducing mastectomy should be offered to women with LFS as an option to reduce primary breast cancer risk.[88] LFS patients with breast cancer should be encouraged to consider mastectomy, rather than lumpectomy, to minimize the risk of developing new primary breast cancers and to avoid developing radiation-induced malignancies.[88, 112]

Mammography has diminished efficacy in women with LFS, predominantly due to the increased mammographic densities seen in these young premenopausal women.[118, 119] In addition to limiting the effectiveness of mammography, increased mammographic densities have been associated with elevated breast cancer risk in women with hereditary and sporadic forms of breast cancer.[120, 121] Because interventions that modify hormone effect (e.g., oophorectomy and Tamoxifen) have been shown to reduce mammographic densities and breast cancer risks in younger women, Weitzel et al. developed an open label pilot study to test the efficacy, safety, and tolerability of a novel hormone-based approach to chemoprevention in young women at risk for hereditary breast cancer.[122] Weitzel’s hormonal chemoprevention regimen included daily intranasal sprays of the gonadotropin-releasing hormone agonist, deslorelin, combined with ultralow-dose estradiol, replacement testosterone, and intermittent doses of oral medroxyprogesterone acetate. In this small series (n=6) of premenopausal women with germline BRCA1 mutations, mammographic density was significantly reduced at 12 months (median absolute decrease, 8.3%; P = 0.043; representing a 29.2% median reduction in mammographic percent density). This study suggests that hormone-based chemoprevention options may expand the non-surgical cancer risk reduction options available to women with LFS.

8. Case Example[95, 123]

The proband was a 31-year-old male who had been diagnosed with aplastic anemia at 22 years old for which he received an allogeneic hematopoietic stem cell transplantation (HSCT). His family history (see pedigree, figure 3) was significant for a son who was diagnosed with CPC just before one year of age. The proband’s father was diagnosed with lung cancer at age 60 and died at age 62. The proband presented for TP53 testing after his son was found to have a TP53 mutation. Due to his prior history of HSCT, a buccal sample was submitted for testing and was found to contain wild-type (normal) TP53. His wife was also tested and found to carry wild-type TP53. At this point, it was determined that even a buccal specimen would contain mostly donor DNA (due to peripheral blood contamination) and that a tissue biopsy would be needed. A tissue sample from the proband was analyzed and a deleterious TP53 mutation was identified. The proband had another child, a 4-year-old asymptomatic daughter, who was tested and found to carry the same TP53mutation. Given the mutation and her brother’s history, she underwent a brain MRI and two tumors were identified: a low grade glioma and a CPC. Since her initial diagnosis she has done very well, with no recurrence of the choroid plexus carcinoma. However, later an abdominal ultrasound detected an adrenal cortical carcinoma, which was resected, and she has remained in complete remission. Unfortunately, the proband’s son passed away a short time later. Despite the tragedy, this remarkably resilient family was able to see the potential importance of the genetic approach and became founding members of a new advocacy and support group for families with TP53 mutations.

Fig. 3

Pedigree for the family described in the case example

(The LFS Association;

8.1. Case Discussion

There are many genetic testing and genetic counseling issues to consider in this case example. Since aplastic anemia is not one of the typical LFS malignancies, the only criterion for TP53 testing that was met was the 2009 Chompret criteria, due to the CPC in the son. As discussed above, testing for TP53 mutations in children has been quite controversial in the past, but is gaining acceptance due to recent data showing a benefit from screening regimens. This case is an excellent example of how testing the second child for the previously identified mutation allowed for the screening and early detection of malignancy and, ultimately, improved survival. Another important consideration is that of genetic testing in individuals who have had HSCT. While genetic testing is usually performed on DNA isolated from a blood sample, this would not be accurate in individuals who have undergone HSCT as the DNA in their blood would be that of their donors. In these cases, a tissue sample that will provide enough DNA for analysis must be provided, such as a skin biopsy or sperm sample, from which lymphocytes can be cultured. The last issue related to this case is that of PGD. This particular couple was not interested in having more children, but PGD is an option that should be discussed for families with LFS.

9. Treatment of TP53-Related Malignancies

9.1. Choroid Plexus Carcinomas

Choroid plexus carcinomas (CPCs) are associated with extremely poor outcomes in the pediatric patient population. Typically these patients require treatment with aggressive protocols that include myelosuppressive chemotherapy and brain radiation (with significant developmental and intellectual consequences).[65, 124] In a recent study of 64 choroid plexus tumors from children (with and without LFS), more than 90% of CPCs demonstrated TP53 dysfunction, either due to deleterious TP53 germline mutations (~50%) or due to somatic TP53 sequence variants involving TP53 codon 72 or MDM SNP 309.[125] High-resolution single nucleotide polymorphism (SNP) arrays revealed extremely high total structural variation (TSV) in TP53-mutated CPC tumor genomes (p=0.006 in mutated vs. TP53 wild-type tumors; p=0.004 in mutated vs. CP papillomas).[125] High TSV levels were predictive of tumor progression (p< 0.001).[125]In addition, 14 out of 16 children with TP53 wild-type tumors had significantly favorable outcomes without radiation with a mean follow-up time of 10.2 years (range, 2.4 to 20 years). This and similar studies[65, 124,125] show that children with CPCs can be stratified based on TP53 mutational status into favorable and unfavorable risk groups, allowing a subset of children to benefit from the opportunity to avoid radiation therapy. In addition to advancements in risk stratification, novel therapeutic options are being explored as well. For instance, Poly (ADP-ribose) polymerase-1 (PARP1), a DNA repair protein, has been studied in an assortment of malignancies and may be protective against therapy-induced DNA damage. There is early evidence that PARP inhibition may be a therapeutic target that can trigger selective cell death in high-grade brain cancers (including choroid plexus carcinomas).[126]

9.2. Hematopoietic Malignancies-Stem Cell Transplantation

TP53 mutation carriers are 100 times more likely to develop leukemia; however, only three percent of LFS patients develop a hematopoietic malignancy. LFS-associated leukemia tends to be very aggressive and is associated with a poor prognosis, complex karyotypes, and chromosome abnormalities seen in patients with therapy-related myelodysplastic syndrome.[11] TP53 alterations were the first biological marker to become incorporated in risk stratification and upfront treatment decisions for chronic lymphocytic leukemia (CLL) patients treated on randomized clinical trials.[127, 128] TP53 inactivation in CLL predicts for an ultra high-risk group of patients with fludarabine-resistant disease and median survival times of less than 12 months.[128131] Therefore, the European Research Initiative on CLL, has recommended that TP53 mutation analysis be performed for all CLL patients and that those with TP53 mutations be considered for allogeneic stem cell transplantation in first remission. Studies have shown that Alemtuzumab-based regimens may provide complete responses in this treatment-resistant group of patients.[132]

10. Future Directions for Therapies

A number of strategies have been explored to target TP53-associated cancers and improve outcomes for patients with somatic and germline TP53 mutations. For instance, single gene targeting strategies that utilize viral vectors (such as Advexin and ONYX-015) have shown some promise.[4, 133135] However, current approaches target more generalized TP53 pathway functions, aiming for low toxicity profiles that could support the possibility of incorporating these therapies into multi-agent combination regimens. A few representative approaches are described below.

10.1. Monoclonal Antibodies

Monoclonal antibodies have been shown to improve outcomes in several disease types, including some promising laboratory and early-phase clinical trials showing an apoptotic affect against TP53-associated leukemia.[136, 137] Humanized monoclonal antibodies such as Trastuzumab (Herceptin®) are currently being used to treat several malignancies, including breast and stomach cancer.[138, 139] Trastuzumab binds to the extracellular domain of the human epidermal growth factor receptor type 2 (HER2), inhibiting cell growth, and targeting cancer cells for destruction by the patient’s immune system. Trastuzumab has been shown to significantly improve outcomes for the 20-30% of patients with HER2-positive breast cancer; this includes patients with metastatic disease that are unlikely to be cured by any other means.[140, 141] Recent studies have begun to identify a unique LFS-breast cancer phenotype that is ductal in histology with estrogen, progesterone, and HER2 receptor positivity.[5658] This HER2 positive phenotype suggests that clinical trials, which incorporate Trastuzumab into front-line therapy for young women with LFS-breast cancer, should be considered.

10.2. Small Molecules

Various small molecules are being explored to try to restore normal TP53 function to deficient cells. Reactivation of wild-type TP53 activity can be a successful strategy and has caused regression of lymphoma and liver cancer in TP53 deficient in vivo model systems.[142144] A number of promising small molecules have been identified using in silico drug screening technologies. These small molecules (currently named PhiKan083, PRIMA-1, CP31398, WR1065, MIRA-1, STIMA-1, RETRA, Nutlin -3, and RITA) reactivateTP53 functional pathways using mechanisms such as raising the melting temperature of the mutant protein to trigger reactivation of function, normalizing the folding conformation of the mutant protein to restore its ability to bind to DNA, or reactivating TP53 wild-type function in TP53-associated cancers.[145150]Although promising, the strategy of TP53 reactivation much be approached with some caution because of reports that increased TP53 expression is associated with treatment resistance in breast cancer.[151]

10.3. Metabolic Therapy

Autophagy is an evolutionarily conserved process of self-degradation of cellular components such as very long-lived proteins and damaged (or excessive numbers of) organelles. Current research suggests that autophagy has two somewhat contradictory functions. It protects the host by suppressing early stages of tumor development, yet it supports the survival of established tumors that are threatened by starvation or chemotherapy. TP53 regulates the expression of key genes in the pathways required for both autophagy and adaptive metabolic responses to stressors through the AMPK and mTOR pathways.[78] Metformin is a drug that regulates cellular metabolism by activating the TP53-AMPK pathway.

Metformin is a well tolerated, commercially available drug, commonly used to treat type II diabetes mellitus. Epidemiological studies have shown decreased cancers in diabetes patients receiving treatment with Metformin.[152155] This clinical observation has been supported by preclinical reports showing that Metformin preferentially inhibits growth of cells lacking functional TP53.[156] Similarly, studies of TP53deficient mice have shown prolonged overall survival of more than 5 months when treated with Metformin. These observations are very encouraging and clinical trials aimed at using Metformin to reduce cancer risk in LFS patients are under consideration by members of the Li-Fraumeni Exploration research Consortium (

10.4. Heavy Ion Cancer Therapy

Heavy Ion radiation therapy utilizes charged particles (heavier than helium ions) to give increased dosages of precisely targeted radiation to cancers, achieving good cancer control while minimizing damage to nearby organs. This highly effective form of linear energy transfer has been shown to induce cell death in a TP53-independent manner (possibly through a pathway that activates the mitochondrial apoptotic factor, caspase 9). These findings suggest that heavy ion therapy may be a very well tolerated way to improve outcomes for patients with TP53 mutated or TP53 null cancers. The practical application of this technology is limited by prohibitive costs and the need for impractical, huge, accelerators; thus, there are only a few heavy-ion facilities available worldwide. Even so, advances in TP53-independent apoptosis-related gene pathways could lead to similar, more near-term applications of heavy ion therapies that target aberrant TP53-associated pathways.[157]

11. Summary

Although most TP53 targeted therapies are still in the early phases of testing, the field of TP53 directed research remains very active and is expanding rapidly. Notably, a workshop on November 2, 2010, at the National Institutes of Health in Bethesda, Maryland, brought together clinicians and scientists, as well as individuals from families with LFS, to review the state of the science, address clinical management issues, stimulate collaborative research, and engage the LFS patient community. This workshop led to the creation of the Li-Fraumeni Exploration (LiFE) Research Consortium, to promote a better understanding of the syndrome and the improvement of the lives of individuals with LFS.[123] Following that inaugural meeting, the LFS Association ( was created as a resource designed to provide a wide range of information, advocacy, and support services for individuals and families with Li-Fraumeni Syndrome. The newly established advocacy group was created to facilitate effective communications, among other tasks, between LFS families and the clinical and scientific members of the research consortium. By summarizing these forty years worth of dedicated efforts to advance treatment and cancer prevention options for people with this rare syndrome, we hope to encourage and provide a voice for our international group of research partners and the LFS patients and families who are living each day for a better tomorrow.


The project described was supported in part by grant numbers RC4CA153828 and R25CA085771 (PI: J. Weitzel) from the National Cancer Institute. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Cancer Institute or the National Institutes of Health.

The authors wish to acknowledge Tracy Sulkin for assistance with manuscript preparation.


Conflict of interest: The authors state that they have no financial relationship with the funders.


1. Gonzalez KD, Noltner KA, Buzin CH, et al. Beyond Li–Fraumeni Syndrome: clinical characteristics of families with p53 germline mutations. J Clin Oncol. 2009;27(8):1250–6. [PubMed]
2. Varley JM, Evans DG, Birch JM. Li-Fraumeni syndrome–a molecular and clinical review. Br J Cancer.1997;76(1):1–14. [PMC free article] [PubMed]
3. Lustbader ED, Williams WR, Bondy ML, et al. Segregation analysis of cancer in families of childhood soft-tissue-sarcoma patients. Am J Hum Genet. 1992;51(2):344–56. [PMC free article] [PubMed]
4. Upton B, Chu Q, Li BD. Li-Fraumeni syndrome: the genetics and treatment considerations for the sarcoma and associated neoplasms. Surgical oncology clinics of North America. 2009;18(1):145–56. ix.[PubMed]
5. Siegel R, Naishadham D, Jemal A. Cancer statistics, 2012. CA Cancer J Clin. 2012;62(1):10–29.[PubMed]
6. Hisada M, Garber JE, Fung CY, et al. Multiple primary cancers in families with Li-Fraumeni syndrome. J Natl Cancer Inst. 1998;90(8):606–11. [PubMed]
7. Curiel-Lewandrowski C, Speetzen LS, Cranmer L, et al. Multiple primary cutaneous melanomas in Li-Fraumeni syndrome. Arch Dermatol. 2011;147(2):248–50. [PubMed]
8. Izawa N, Matsumoto S, Manabe J, et al. A Japanese patient with Li-Fraumeni syndrome who had nine primary malignancies associated with a germline mutation of the p53 tumor-suppressor gene. Int J Clin Oncol / Jpn Soc Clin Oncol. 2008;13(1):78–82. [PubMed]
9. Strong LC, Stine M, Norsted TL. Cancer in survivors of childhood soft tissue sarcoma and their relatives.J Natl Cancer Inst. 1987;79(6):1213–20. [PubMed]
10. Hwang SJ, Lozano G, Amos CI, et al. Germline p53 mutations in a cohort with childhood sarcoma: sex differences in cancer risk. Am J Hum Genet. 2003;72(4):975–83. [PMC free article] [PubMed]
11. Talwalkar SS, Yin CC, Naeem RC, et al. Myelodysplastic syndromes arising in patients with germline TP53 mutation and Li-Fraumeni syndrome. Arch Pathol Lab Med. 2010;134(7):1010–5. [PubMed]
12. Henry E, Villalobos V, Million L, et al. Chest wall leiomyosarcoma after breast-conservative therapy for early-stage breast cancer in a young woman with Li-Fraumeni syndrome. J Natl Compr Canc Netw.2012;10(8):939–42. [PubMed]
13. Kress M, May E, Cassingena R, et al. Simian virus 40-transformed cells express new species of proteins precipitable by anti-simian virus 40 tumor serum. J Virol. 1979;31(2):472–83. [PMC free article] [PubMed]
14. Lane DP, Crawford LV. T antigen is bound to a host protein in SV40-transformed cells. Nature.1979;278(5701):261–3. [PubMed]
15. Linzer DI, Levine AJ. Characterization of a 54K dalton cellular SV40 tumor antigen present in SV40-transformed cells and uninfected embryonal carcinoma cells. Cell. 1979;17(1):43–52. [PubMed]
16. Soussi T. The history of p53. A perfect example of the drawbacks of scientific paradigms. EMBO reports. 2010;11(11):822–6. [PMC free article] [PubMed]
17. Diller L, Kassel J, Nelson CE, et al. p53 functions as a cell cycle control protein in osteosarcomas.Molecular and cellular biology. 1990;10(11):5772–81. [PMC free article] [PubMed]
18. Baker SJ, Markowitz S, Fearon ER, et al. Suppression of human colorectal carcinoma cell growth by wild-type p53. Science. 1990;249(4971):912–5. [PubMed]
19. Levine AJ, Momand J, Finlay CA. The p53 tumour suppressor gene. Nature. 1991;351:453–6.[PubMed]
20. Lane DP. Cancer. p53, guardian of the genome. Nature. 1992;358(6381):15–6. [PubMed]
21. Petitjean A, Mathe E, Kato S, et al. Impact of mutant p53 functional properties on TP53 mutation patterns and tumor phenotype: lessons from recent developments in the IARC TP53 database. Hum Mutat.2007;28(6):622–9. [PubMed]
22. Tabori U, Baskin B, Shago M, et al. Universal poor survival in children with medulloblastoma harboring somatic TP53 mutations. J Clin Oncol. 2010 Mar 10;28(8):1345–50. [PubMed]
23. Olivier M, Langerod A, Carrieri P, et al. The clinical value of somatic TP53 gene mutations in 1,794 patients with breast cancer. Clin Cancer Res. 2006;12(4):1157–67. [PubMed]
24. Fernandez-Cuesta L, Oakman C, Falagan-Lotsch P, et al. Prognostic and predictive value of TP53 mutations in node-positive breast cancer patients treated with anthracycline- or anthracycline/taxane-based adjuvant therapy: results from the BIG 02-98 phase III trial. Breast Cancer Res. 2012;14(3):R70.[PMC free article] [PubMed]
25. Linzer DI, Maltzman W, Levine AJ. The SV40 A gene product is required for the production of a 54,000 MW cellular tumor antigen. Virology. 1979;98(2):308–18. [PubMed]
26. DeLeo AB, Jay G, Appella E, et al. Detection of a transformation-related antigen in chemically induced sarcomas and other transformed cells of the mouse. P Natl Acad Sci USA. 1979;76(5):2420–4.[PMC free article] [PubMed]
27. Crawford L. The 53,000-dalton cellular protein and its role in transformation. Int Rev Exp Pathol.1983;25:1–50. [PubMed]
28. Crawford LV, Pim DC, Gurney EG, et al. Detection of a common feature in several human tumor cell lines–a 53,000-dalton protein. P Natl Acad Sci USA. 1981;78(1):41–5. [PMC free article] [PubMed]
29. Crawford LV, Pim DC, Lamb P. The cellular protein p53 in human tumours. Mol Biol Med.1984;2(4):261–72. [PubMed]
30. Koeffler HP, Miller C, Nicolson MA, et al. Increased expression of p53 protein in human leukemia cells.P Natl Acad Sci USA. 1986;83(11):4035–9. [PMC free article] [PubMed]
31. Lubbert M, Miller CW, Crawford L, et al. p53 in chronic myelogenous leukemia. Study of mechanisms of differential expression. J Exp Med. 1988;167(3):873–86. [PMC free article] [PubMed]
32. Masuda H, Miller C, Koeffler HP, et al. Rearrangement of the p53 gene in human osteogenic sarcomas. P Natl Acad Sci USA. 1987;84(21):7716–9. [PMC free article] [PubMed]
33. Smith LJ, McCulloch EA, Benchimol S. Expression of the p53 oncogene in acute myeloblastic leukemia.J Exp Med. 1986;164(3):751–61. [PMC free article] [PubMed]
34. Lavigueur A, Maltby V, Mock D, et al. High incidence of lung, bone, and lymphoid tumors in transgenic mice overexpressing mutant alleles of the p53 oncogene. Mol Cell Biol. 1989;9(9):3982–91.[PMC free article] [PubMed]
35. Denissenko MF, Pao A, Tang M, et al. Preferential formation of benzo[a]pyrene adducts at lung cancer mutational hotspots in P53. Science. 1996;274(5286):430–2. [PubMed]
36. Hainaut P, Pfeifer GP. Patterns of p53 G–> T transversions in lung cancers reflect the primary mutagenic signature of DNA-damage by tobacco smoke. Carcinogenesis. 2001;22(3):367–74. [PubMed]
37. Besaratinia A, Pfeifer GP. Applications of the human p53 knock-in (Hupki) mouse model for human carcinogen testing. FASEB J. 2010;24(8):2612–9. [PMC free article] [PubMed]
38. Harvey M, McArthur MJ, Montgomery CA, Jr., et al. Genetic background alters the spectrum of tumors that develop in p53-deficient mice. FASEB J. 1993;7(10):938–43. [PubMed]
39. Donehower LA, Harvey M, Slagle BL, et al. Mice deficient for p53 are developmentally normal but susceptible to spontaneous tumours. Nature. 1992;356(6366):215–21. [PubMed]
40. Jacks T, Remington L, Williams BO, et al. Tumor spectrum analysis in p53-mutant mice. Curr Biol.1994;4(1):1–7. [PubMed]
41. Vogelstein B. Cancer. A deadly inheritance. Nature. 1990;348(6303):681–2. [PubMed]
42. Li FP, Fraumeni JF., Jr. Rhabdomyosarcoma in children: epidemiologic study and identification of a familial cancer syndrome. J Natl Cancer Inst. 1969;43(6):1365–73. [PubMed]
43. Li FP, Fraumeni JF, Jr., Mulvihill JJ, et al. A cancer family syndrome in twenty-four kindreds. Cancer Res. 1988;48(18):5358–62. [PubMed]
44. Lynch HT, Mulcahy GM, Harris RE, et al. Genetic and pathologic findings in a kindred with hereditary sarcoma, breast cancer, brain tumors, leukemia, lung, laryngeal, and adrenal cortical carcinoma. Cancer.1978;41(5):2055–64. [PubMed]
45. Malkin D, Li FP, Strong LC, et al. Germ line p53 mutations in a familial syndrome of breast cancer, sarcomas, and other neoplasms. Science. 1990;250:1233–7. [PubMed]
46. Srivastava S, Zou ZQ, Pirollo K, et al. Germ-line transmission of a mutated p53 gene in a cancer-prone family with Li-Fraumeni syndrome. Nature. 1990;348(6303):747–9. [PubMed]
47. Borresen AL, Andersen TI, Garber J, et al. Screening for germ line TP53 mutations in breast cancer ptients. Cancer Res. 1992;52:3234–6. [PubMed]
48. Birch JM. Germline mutations in the p53 tumour suppressor gene: scientific, clinical and ethical challenges. Br J Cancer. 1992;66(3):424–6. [PMC free article] [PubMed]
49. Law JC, Strong LC, Chidambaram A, et al. A germ line mutation in exon 5 of the p53 gene in an extended cancer family. Cancer Res. 1991;51(23 Pt 1):6385–7. [PubMed]
50. Strong LC, Williams WR, Tainsky MA. The Li-Fraumeni syndrome: from clinical epidemiology to molecular genetics. Am J Epidemiol. 1992;135(2):190–9. [PubMed]
51. Olivier M, Goldgar DE, Sodha N, et al. Li-Fraumeni and related syndromes: correlation between tumor type, family structure, and TP53 genotype. Cancer Res. 2003;63(20):6643–50. [PubMed]
52. Garritano S, Gemignani F, Palmero EI, et al. Detailed haplotype analysis at the TP53 locus in p.R337H mutation carriers in the population of Southern Brazil: evidence for a founder effect. Hum Mutat.2010;31(2):143–50. [PubMed]
53. Chompret A, Brugieres L, Ronsin M, et al. P53 germline mutations in childhood cancers and cancer risk for carrier individuals. Br J Cancer. 2000;82(12):1932–7. [PMC free article] [PubMed]
54. Evans DG, Birch JM, Thorneycroft M, et al. Low rate of TP53 germline mutations in breast cancer/sarcoma families not fulfilling classical criteria for Li-Fraumeni syndrome. J Med Genet.2002;39(12):941–4. [PMC free article] [PubMed]
55. Lee DS, Yoon SY, Looi LM, et al. Comparable frequency of BRCA1, BRCA2 and TP53 germline mutations in a multi-ethnic Asian cohort suggests TP53 screening should be offered together with BRCA1/2 screening to early-onset breast cancer patients. Breast Cancer Res. 2012;14(2):R61. [PMC free article][PubMed]
56. Masciari S, Dillon DA, Rath M, et al. Breast cancer phenotype in women with TP53 germline mutations: a Li-Fraumeni syndrome consortium effort. Breast Cancer Res Treat. 2012;133(3):1125–30.[PMC free article] [PubMed]
57. Melhem-Bertrandt A, Bojadzieva J, Ready KJ, et al. Early onset HER2-positive breast cancer is associated with germline TP53 mutations. Cancer. 2012;118(4):908–13. [PMC free article] [PubMed]
58. Wilson JR, Bateman AC, Hanson H, et al. A novel HER2-positive breast cancer phenotype arising from germline TP53 mutations. J Med Genet. 2010;47(11):771–4. [PubMed]
59. Ognjanovic S, Oliver M, Bergemann TL, et al. Sarcomas in TP53 germline mutation carriers: A review of the IARC TP53 database. Cancer. 2012 [PubMed]
60. Palmero EI, Achatz MIW, Ashton-Prolla P, et al. Tumor protein 53 mutations and inherited cancer: beyond Li-Fraumeni syndrome. Curr Opin Oncol. 2010;22(1):64–9. [PubMed]
61. Ruijs MW, Verhoef S, Rookus MA, et al. TP53 germline mutation testing in 180 families suspected of Li-Fraumeni syndrome: mutation detection rate and relative frequency of cancers in different familial phenotypes. J Med Genet. 2010;47(6):421–8. [PubMed]
62. Farrell CJ, Plotkin SR. Genetic causes of brain tumors: neurofibromatosis, tuberous sclerosis, von Hippel-Lindau, and other syndromes. Neurol Clin. 2007;25(4):925–46. viii. [PubMed]
63. Krutilkova V, Trkova M, Fleitz J, et al. Identification of five new families strengthens the link between childhood choroid plexus carcinoma and germline TP53 mutations. Eur J Cancer. 2005;41(11):1597–603.[PubMed]
64. Garber JE, Burke EM, Lavally BL, et al. Choroid plexus tumors in the breast cancer-sarcoma syndrome.Cancer. 1990;66(12):2658–60. [PubMed]
65. Gozali AE, Britt B, Shane L, et al. Choroid plexus tumors; management, outcome, and association with the Li-Fraumeni syndrome: the Children’s Hospital Los Angeles (CHLA) experience, 1991-2010. Pediatr Blood Cancer. 2012;58(6):905–9. [PubMed]
66. Herrmann LJ, Heinze B, Fassnacht M, et al. TP53 germline mutations in adult patients with adrenocortical carcinoma. J Clin Endocrinol Metab. 2012;97(3):E476–85. [PubMed]
67. Palmero EI, Schuler-Faccini L, Caleffi M, et al. Detection of R337H, a germline TP53 mutation predisposing to multiple cancers, in asymptomatic women participating in a breast cancer screening program in Southern Brazil. Cancer Lett. 2008;261(1):21–5. [PubMed]
68. Achatz MIW, Hainaut P, Ashton-Prolla P. Highly prevalent TP53 mutation predisposing to many cancers in the Brazilian population: a case for newborn screening? Lancet Oncol. 2009;10(9):920–5. [PubMed]
69. Pinto EM, Billerbeck AE, Villares MC, et al. Founder effect for the highly prevalent R337H mutation of tumor suppressor p53 in Brazilian patients with adrenocortical tumors. Arq Bras Endocrinol Metabol.2004;48(5):647–50. [PubMed]
70. Ribeiro RC, Sandrini F, Figueiredo B, et al. An inherited p53 mutation that contributes in a tissue-specific manner to pediatric adrenal cortical carcinoma. P Natl Acad Sci USA. 2001;98(16):9330–5.[PMC free article] [PubMed]
71. Latronico AC, Pinto EM, Domenice S, et al. An inherited mutation outside the highly conserved DNA-binding domain of the p53 tumor suppressor protein in children and adults with sporadic adrenocortical tumors. J Clin Endocrinol Metab. 2001;86(10):4970–3. [PubMed]
72. Figueiredo BC, Sandrini R, Zambetti GP, et al. Penetrance of adrenocortical tumours associated with the germline TP53 R337H mutation. J Med Genet. 2006;43(1):91–6. [PMC free article] [PubMed]
73. Achatz MI, Olivier M, Le Calvez F, et al. The TP53 mutation, R337H, is associated with Li-Fraumeni and Li-Fraumeni-like syndromes in Brazilian families. Cancer Lett. 2007;245(1-2):96–102. [PubMed]
74. Assumpcao JG, Seidinger AL, Mastellaro MJ, et al. Association of the germline TP53 R337H mutation with breast cancer in southern Brazil. BMC Cancer. 2008;8:357. [PMC free article] [PubMed]
75. Wong P, Verselis SJ, Garber JE, et al. Prevalence of early onset colorectal cancer in 397 patients with classic Li-Fraumeni syndrome. Gastroenterology. 2006;130(1):73–9. [PubMed]
76. Masciari S, Dewanwala A, Stoffel EM, et al. Gastric cancer in individuals with Li-Fraumeni syndrome.Genet Med. 2011;13(7):651–7. [PMC free article] [PubMed]
77. Walsh T, Casadei S, Lee MK, et al. Mutations in 12 genes for inherited ovarian, fallopian tube, and peritoneal carcinoma identified by massively parallel sequencing. P Natl Acad Sci USA.2011;108(44):18032–7. [PMC free article] [PubMed]
78. Sui X, Jin L, Huang X, et al. p53 signaling and autophagy in cancer: a revolutionary strategy could be developed for cancer treatment. Autophagy. 2011;7(6):565–71. [PubMed]
79. Sigal A, Rotter V. Oncogenic mutations of the p53 tumor suppressor: the demons of the guardian of the genome. Cancer Res. 2000;60(24):6788–93. [PubMed]
80. Brosh R, Rotter V. When mutants gain new powers: news from the mutant p53 field. Nat Rev Cancer.2009;9(10):701–13. [PubMed]
81. Malkin D. Li-Fraumeni syndrome. Genes Cancer. 2011;2(4):475–84. [PMC free article] [PubMed]
82. Varley J, McGown G, Thorncroft M, et al. Are there low-penetrance TP53 alleles? Evidence from childhood adrenocortical tumors. Am J Hum Genet. 1999;65:995–1006. [PMC free article] [PubMed]
83. Birch JM, Hartley AL, Tricker KJ, et al. Prevalence and diversity of constitutional mutations in the p53 gene among 21 Li-Fraumeni families. Cancer Res. 1994;54(5):1298–304. [PubMed]
84. Bougeard G, Sesboue R, Baert-Desurmont S, et al. Molecular basis of the Li-Fraumeni syndrome: an update from the French LFS families. J Med Genet. 2008;45(8):535–8. [PubMed]
85. Andreotti V, Ciribilli Y, Monti P, et al. p53 transactivation and the impact of mutations, cofactors and small molecules using a simplified yeast-based screening system. PloS One. 2011;6(6):e20643.[PMC free article] [PubMed]
86. Horgan AM, Yang B, Azad AK, et al. Pharmacogenetic and germline prognostic markers of lung cancer.J Thorac Oncol. 2011;6(2):296–304. [PubMed]
87. Medical Genetics Information Resource. University of Washington; Seattle: [Accessed July 19, 2012]. 1993. GeneTests. 1993. Available at:
88. NCCN [Accessed June 1, 2012];NCCN clinical practice guidelines in oncology V.1.2012: Genetic/familial high-risk assessment: breast and ovarian. NCCN Clinical Practice Guidelines. 2012Available at:
89. Eeles RA. Germline mutations in the TP53 gene. Cancer Surv. 1995;25:101–24. [PubMed]
90. Chompret A, Abel A, Stoppa-Lyonnet D, et al. Sensitivity and predictive value of criteria for p53 germline mutation screening. J Med Genet. 2001;38(1):43–7. [PMC free article] [PubMed]
91. Tinat J, Bougeard G, Baert-Desurmont S, et al. 2009 version of the Chompret criteria for Li Fraumeni syndrome. J Clin Oncol. 2009;27(26):e108–9. reply to J. Tinat e10. [PubMed]
92. McCuaig JM, Armel SR, Novokmet A, et al. Routine TP53 testing for breast cancer under age 30: ready for prime time? Fam Cancer. 2012 [PubMed]
93. Gonzalez KD, Buzin CH, Noltner KA, et al. High frequency of de novo mutations in Li-Fraumeni syndrome. J Med Genet. 2009;46(10):689–93. [PubMed]
94. Evans D, Lunt P, Clancy T, et al. Childhood predictive genetic testing for Li–Fraumeni syndrome. Fam Cancer. 2010;9(1):65–9. [PubMed]
95. Villani A, Tabori U, Schiffman J, et al. Biochemical and imaging surveillance in germline TP53 mutation carriers with Li-Fraumeni syndrome: a prospective observational study. The Lancet Oncology.2011;12(6):559–67. [PubMed]
96. Rechitsky S, Verlinsky O, Chistokhina A, et al. Preimplantation genetic diagnosis for cancer predisposition. Reproductive Biomedicine Online. 2002;5(2):148–55. [PubMed]
97. Offit K, Sagi M, Hurley K. Preimplantation genetic diagnosis for cancer syndromes: a new challenge for preventive medicine. JAMA. 2006;296(22):2727–30. [PubMed]
98. Verlinsky Y, Rechitsky S, Verlinsky O, et al. Preimplantation diagnosis for p53 tumour suppressor gene mutations. Reproductive biomedicine online. 2001;2(2):102–5. [PubMed]
99. Avigad S, Peleg D, Barel D, et al. Prenatal diagnosis in Li-Fraumeni syndrome. J Pediatr Hematol Oncol.2004;26(9):541–5. [PubMed]
100. Peterson SK, Pentz RD, Marani SK, et al. Psychological functioning in persons considering genetic counseling and testing for Li-Fraumeni syndrome. Psychooncology. 2008;17(8):783–9. [PubMed]
101. Lammens CR, Aaronson NK, Wagner A, et al. Genetic testing in Li-Fraumeni syndrome: uptake and psychosocial consequences. J Clin Oncol. 2010;28(18):3008–14. [PubMed]
102. Lammens CR, Bleiker EM, Verhoef S, et al. Distress in partners of individuals diagnosed with or at high risk of developing tumors due to rare hereditary cancer syndromes. Psychooncology. 2011;20(6):631–8.[PubMed]
103. Storm C, Agarwal R, Offit K. Ethical and legal implications of cancer genetic testing: do physicians have a duty to warn patients’ relatives about possible genetic risks? J Oncol Pract. 2008;4(5):229–30.[PMC free article] [PubMed]
104. Schwarzbraun T, Obenauf AC, Langmann A, et al. Predictive diagnosis of the cancer prone Li-Fraumeni syndrome by accident: new challenges through whole genome array testing. J Med Genet. 2009 May 1;46(5):341–4. 2009. [PMC free article] [PubMed]
105. Link DC, Schuettpelz LG, Shen D, et al. Identification of a novel TP53 cancer susceptibility mutation through whole-genome sequencing of a patient with therapy-related AML. JAMA. 2011;305(15):1568–76.[PMC free article] [PubMed]
106. Engstrom PF, Bloom MG, Demetri GD, et al. NCCN molecular testing white paper: effectiveness, efficiency, and reimbursement. J Natl Compr Canc Netw. 2011;9(Suppl 6):S1–16. [PubMed]
107. NCCN panel calls for higher standards, better ways of translating molecular genetics into clinical practice. J Natl Compr Canc Netw. 2011;9(4):xliii. [PubMed]
108. McClure JS. Informing patients: translating the NCCN guidelines. J Natl Compr Canc Netw.2011;9(Suppl 3):S4–5. [PubMed]
109. Netzer C, Klein C, Kohlhase J, et al. New challenges for informed consent through whole genome array testing. J Med Genet. 2009;46(7):495–6. [PubMed]
110. Lehman CD, Smith RA. The role of MRI in breast cancer screening. J Natl Compr Canc Netw.2009;7(10):1109–15. [PubMed]
111. Saslow D, Boetes C, Burke W, et al. American Cancer Society guidelines for breast screening with MRI as an adjunct to mammography. CA Cancer J Clin. 2007;57(2):75–89. [PubMed]
112. Schneider K, Garber J. Li-Fraumeni syndrome. In: Pagon RA, Bird TD, Dolan CR, Stephens K, Adam MP, editors. GeneReviews. University of Washington, Seattle; Seattle WA: 1993.
113. Masciari S, Van den Abbeele AD, Diller LR, et al. F18-Fluorodeoxyglucose-positron emission tomography/computed tomography screening in Li-Fraumeni syndrome. JAMA. 2008;299(11):1315–9.[PubMed]
114. Monsalve J, Kapur J, Malkin D, et al. Radiographics : a review. 1. Vol. 31. publication of the Radiological Society of North America, Inc.; 2011. Imaging of cancer predisposition syndromes in children; pp. 263–80. [PubMed]
115. Shlien A, Tabori U, Marshall CR, et al. Excessive genomic DNA copy number variation in the Li-Fraumeni cancer predisposition syndrome. P Natl Acad Sci USA. 2008;105(32):11264–9. [PMC free article][PubMed]
116. Tabori U, Dome JS. Telomere biology of pediatric cancer. Cancer Invest. 2007;25(3):197–208.[PubMed]
117. Tabori U, Nanda S, Druker H, et al. Younger age of cancer initiation is associated with shorter telomere length in Li-Fraumeni syndrome. Cancer Res. 2007;67(4):1415–8. [PubMed]
118. Ma L, Fishell E, Wright B, et al. Case-control study of factors associated with failure to detect breast cancer by mammography. J Natl Cancer Inst. 1992 May 20;84(10):781–5. [PubMed]
119. Kriege M, Brekelmans CT, Boetes C, et al. Efficacy of MRI and mammography for breast-cancer screening in women with a familial or genetic predisposition. New Engl J Med. 2004;351(5):427–37.[PubMed]
120. Boyd NF, Dite GS, Stone J, et al. Heritability of mammographic density, a risk factor for breast cancer.New Engl J Med. 2002;347(12):886–94. [PubMed]
121. Boyd NF, Jensen HM, Cooke G, et al. Relationship between mammographic and histological risk factors for breast cancer. J Natl Cancer Inst. 1992 Aug 5;84(15):1170–9. [PubMed]
122. Weitzel JN, Buys SS, Sherman WH, et al. Reduced mammographic density with use of a gonadotropin-releasing hormone agonist-based chemoprevention regimen in BRCA1 carriers. Clin Cancer Res. 2007;13(2 Pt 1):654–8. [PubMed]
123. Mai PL, Malkin D, Garber JE, et al. Li-Fraumeni syndrome: Report of a clinical research workshop and creation of a research consortium. Cancer Genet. 2012;205(10):479–87. [PMC free article] [PubMed]
124. Berrak SG, Liu DD, Wrede B, et al. Which therapy works better in choroid plexus carcinomas? J Neurooncol. 2011;103(1):155–62. [PubMed]
125. Tabori U, Shlien A, Baskin B, et al. TP53 alterations determine clinical subgroups and survival of patients with choroid plexus tumors. J Clin Oncol. 2010;28(12):1995–2001. [PubMed]
126. Barton VN, Donson AM, Kleinschmidt-DeMasters BK, et al. PARP1 expression in pediatric central nervous system tumors. Pediatr Blood Cancer. 2009;53(7):1227–30. [PubMed]
127. Zenz T, Mertens D, Dohner H, et al. Molecular diagnostics in chronic lymphocytic leukemia – pathogenetic and clinical implications. Leuk Lymphoma. 2008;49(5):864–73. [PubMed]
128. Veliz M, Pinilla-Ibarz J. Treatment of relapsed or refractory chronic lymphocytic leukemia. Cancer Control: Journal of the Moffitt Cancer Center. 2012;19(1):37–53. [PubMed]
129. Keating MJ, O’Brien S, Kontoyiannis D, et al. Results of first salvage therapy for patients refractory to a fludarabine regimen in chronic lymphocytic leukemia. Leuk Lymphoma. 2002;43(9):1755–62. [PubMed]
130. Tam CS, O’Brien S, Lerner S, et al. The natural history of fludarabine-refractory chronic lymphocytic leukemia patients who fail alemtuzumab or have bulky lymphadenopathy. Leuk Lymphoma.2007;48(10):1931–9. [PubMed]
131. Dearden CE, Richards S, Else M, et al. A comparison of the efficacy and safety of oral and intravenous fludarabine in chronic lymphocytic leukemia in the LRF CLL4 trial. Cancer. 2010;117(11):2452–2460.[PubMed]
132. Pospisilova S, Gonzalez D, Malcikova J, et al. ERIC recommendations on TP53 mutation analysis in chronic lymphocytic leukemia. Leukemia. 2012;26(7):1458–61. [PubMed]
133. Hallden G, Portella G. Oncolytic virotherapy with modified adenoviruses and novel therapeutic targets.Expert opinion on therapeutic targets. 2012;16(10):945–958. [PubMed]
134. Sakai R, Kagawa S, Yamasaki Y, et al. Preclinical evaluation of differentially targeting dual virotherapy for human solid cancer. Mol Cancer Ther. 2010;9(6):1884–93. [PubMed]
135. Brower V. Cancer gene therapy steadily advances. J Natl Cancer Inst. 2008;100(18):1276–8. [PubMed]
136. Bishop MR, Iversen PL, Bayever E, et al. Phase I trial of an antisense oligonucleotide OL(1)p53 in hematologic malignancies. J Clin Oncol. 1996;14(4):1320–6. [PubMed]
137. Bishop MR, Jackson JD, Tarantolo SR, et al. Ex vivo treatment of bone marrow with phosphorothioate oligonucleotide OL(1)p53 for autologous transplantation in acute myelogenous leukemia and myelodysplastic syndrome. J Hematother. 1997;6(5):441–6. [PubMed]
138. Bang YJ. Advances in the management of HER2-positive advanced gastric and gastroesophageal junction cancer. J Clin Gastroenterol. 2012;46(8):637–48. [PubMed]
139. Jankowitz RC, Brufsky AM. Adjuvant treatment of HER2-positive breast cancer: winning efforts continue to improve HER2-positive patient outcome long-term. Breast Cancer Res. 2012 Apr 30;14(2):308.[PMC free article] [PubMed]
140. Hayashi M, Okumura Y, Osako T, et al. Time to first tumor progression as a predictor of efficacy of continued treatment with trastuzumab beyond progression in human epidermal growth factor receptor 2-positive metastatic breast cancer. Int J Clin Oncol / Jpn Soc Clin Oncol. 2011;16(6):694–700. [PubMed]
141. Sachdev JC, Jahanzeb M. Blockade of the HER family of receptors in the treatment of HER2-positive metastatic breast cancer. Clin Breast Cancer. 2012;12(1):19–29. [PubMed]
142. Xue W, Zender L, Miething C, et al. Senescence and tumour clearance is triggered by p53 restoration in murine liver carcinomas. Nature. 2007;445(7128):656–60. [PMC free article] [PubMed]
143. Martins CP, Brown-Swigart L, Evan GI. Modeling the therapeutic efficacy of p53 restoration in tumors.Cell. 2006;127(7):1323–34. [PubMed]
144. Ventura A, Kirsch DG, McLaughlin ME, et al. Restoration of p53 function leads to tumour regression in vivo. Nature. 2007;445(7128):661–5. [PubMed]
145. Suzuki K, Matsubara H. Recent advances in p53 research and cancer treatment. J Biomed Biotechnol.2011:978312. 2011. [PMC free article] [PubMed]
146. Bykov VJ, Issaeva N, Selivanova G, et al. Mutant p53-dependent growth suppression distinguishes PRIMA-1 from known anticancer drugs: a statistical analysis of information in the National Cancer Institute database. Carcinogenesis. 2002;23(12):2011–8. [PubMed]
147. Rippin TM, Bykov VJ, Freund SM, et al. Characterization of the p53-rescue drug CP-31398 in vitro and in living cells. Oncogene. 2002;21(14):2119–29. [PubMed]
148. Lehmann BD, Pietenpol JA. Targeting mutant p53 in human tumors. J Clin Oncol. 2012;30(29):3648–50. [PubMed]
149. Lehmann S, Bykov VJ, Ali D, et al. Targeting p53 in Vivo: A first-in-human study with p53-targeting compound APR-246 in refractory hematologic malignancies and prostate cancer. J Clin Oncol.2012;30(29):3633–9. [PubMed]
150. Clayman GL, el-Naggar AK, Lippman SM, et al. Adenovirus-mediated p53 gene transfer in patients with advanced recurrent head and neck squamous cell carcinoma. J Clin Oncol. 1998;16(6):2221–32.[PubMed]
151. Bertheau P, Espie M, Turpin E, et al. TP53 status and response to chemotherapy in breast cancer.Pathobiology. 2008;75(2):132–9. [PubMed]
152. Chaiteerakij R, Yang JD, Harmsen WS, et al. Risk factors for intrahepatic cholangiocarcinoma: Association between metformin use and reduced cancer risk. Hepatology. 2012 [ePub ahead of print][PMC free article] [PubMed]
153. Skinner HD, McCurdy MR, Echeverria AE, et al. Metformin use and improved response to therapy in esophageal adenocarcinoma. Acta Oncol. 2012 [Epub ahead of print] [PubMed]
154. Niraula S, Dowling RJ, Ennis M, et al. Metformin in early breast cancer: a prospective window of opportunity neoadjuvant study. Breast Cancer Res Treat. 2012;135(3):821–30. [PubMed]
155. Lee JH, Jeon SM, Hong SP, et al. Metformin use is associated with a decreased incidence of colorectal adenomas in diabetic patients with previous colorectal cancer. Digest Liver Dis. 2012;44(12):1042–7.[PubMed]
156. Buzzai M, Jones RG, Amaravadi RK, et al. Systemic treatment with the antidiabetic drug metformin selectively impairs p53-deficient tumor cell growth. Cancer Res. 2007;67(14):6745–52. [PubMed]
157. Hamada N, Imaoka T, Masunaga S, et al. Recent advances in the biology of heavy-ion cancer therapy. J Radiat Res. 2010;51(4):365–83. [PubMed]
158. Collins LC, Marotti JD, Gelber S, et al. Pathologic features and molecular phenotype by patient age in a large cohort of young women with breast cancer. Breast Cancer Res Treat. 2012;131(3):1061–6. [PubMed]
159. Gonzalez-Angulo AM, Broglio K, Kau SW, et al. Women age < or = 35 years with primary breast carcinoma: disease features at presentation. Cancer. 2005;103(12):2466–72. [PubMed]