The prevalence of germ-line TP53 mutations in women diagnosed with breast cancer before age 30

Pedigree analysis exploring the inconsistency between diverse phenotypes and testing criteria for germline TP53 mutations in Chinese women with breast cancer

PURPOSE

In the present study, we addressed the inconsistency between the testing criteria and diverse phenotypes for germline TP53 mutation in patients with breast cancer in the Chinese population.

METHOD

We proposed a new added item (synchronous or metachronous bilateral breast cancer) as one of the testing criteria (aimed at high-penetrance breast cancer susceptibility genes) and applied it for determining TP53 germline mutation status in 420 female patients with breast cancer using multigene panel-based next-generation sequencing, Sanger sequencing, and mass spectrometry.

RESULTS

We found that 1.4% of patients carried a pathogenic or likely pathogenic germline TP53 mutation. Compared with BRCA mutation carriers (8.0%) and non-carriers (7.1%), TP53 mutation carriers (33.3%) developed breast cancer earlier. The majority of TP53 mutation carriers (66.7%) developed breast cancer after age 30 and had bilateral breast cancer (33.3%). Pedigree investigation of four TP53 carriers and a patient with a TP53 variant of unknown significance revealed that neither of their parents harbored the same mutations as the probands, indicating that the mutations might occur de novo.

CONCLUSION

Our study revealed distinguishing features of TP53 carriers among Chinese women with breast cancer, which is inconsistent with the currently used testing criteria; therefore, the newly proposed testing criteria may be more appropriate.

Germline TP53 pathogenic variants and breast cancer: A narrative review

Approximately 10% of breast cancers are associated with the inheritance of a pathogenic variant (PV) in one of the breast cancer susceptibility genes. Multiple breast cancer predisposing genes, including TP53, are responsible for the increased breast cancer risk. Tumor protein-53 (TP53) germline PVs are associated with Li-Fraumeni syndrome, a rare autosomal dominant inherited cancer predisposition syndrome associated with early-onset pediatric and multiple primary cancers such as soft tissue and bone sarcomas, breast cancer, brain tumors, adrenocortical carcinomas and leukemias. Women harboring a TP53 PV carry a lifetime risk of developing breast cancer of 80-90%. The aim of the present narrative review is to provide a comprehensive overview of the criteria for offering TP53 testing, prevalence of TP53 carriers among patients with breast cancer, and what is known about its prognostic and therapeutic implications. A summary of the current indications of secondary cancer surveillance and survivorship issues are also provided. Finally, the spectrum of TP53 alteration and testing is discussed. The optimal strategies for the treatment of breast cancer in patients harboring TP53 PVs poses certain challenges. Current guidelines favor the option of performing mastectomy rather than lumpectomy to avoid adjuvant radiotherapy and subsequent risk of radiation-induced second primary malignancies, with careful consideration of radiation when indicated post-mastectomy. Some studies suggest that patients with breast cancer and germline TP53 PV might have worse survival outcomes compared to patients with breast cancer and wild type germline TP53 status. Annual breast magnetic resonance imaging (MRI) and whole-body MRI are recommended as secondary prevention.

Medical guidelines for Li-Fraumeni syndrome 2019, version 1.1

Li–Fraumeni syndrome (LFS) is a hereditary tumor that exhibits autosomal dominant inheritance. LFS develops in individuals with a pathogenic germline variant of the cancer-suppressor gene, TP53 (individuals with TP53 pathogenic variant). The number of individuals with TP53 pathogenic variant among the general population is said to be 1 in 500 to 20,000. Meanwhile, it is found in 1.6% (median value, range of 0–6.7%) of patients with pediatric cancer and 0.2% of adult patients with cancer. LFS is diagnosed by the presence of germline TP53 pathogenic variants. However, patients can still be diagnosed with LFS even in the absence of a TP53 pathogenic variant if the familial history of cancers fit the classic LFS diagnostic criteria. It is recommended that TP53 genetic testing be promptly performed if LFS is suspected. Chompret criteria are widely used for the TP53 genetic test. However, as there are a certain number of cases of LFS that do not fit the criteria, if LFS is suspected, TP53 genetic testing should be performed regardless of the criteria. The probability of individuals with TP53 pathogenic variant developing cancer in their lifetime (penetrance) is 75% for men and almost 100% for women. The LFS core tumors (breast cancer, osteosarcoma, soft tissue sarcoma, brain tumor, and adrenocortical cancer) constitute the majority of cases; however, various types of cancers, such as hematological malignancy, epithelial cancer, and pediatric cancers, such as neuroblastoma, can also develop. Furthermore, approximately half of the cases develop simultaneous or metachronous multiple cancers. The types of TP53 pathogenic variants and factors that modify the functions of TP53 have an impact on the clinical presentation, although there are currently no definitive findings. There is currently no cancer preventive agent for individuals with TP53 pathogenic variant. Surgical treatments, such as risk-reducing bilateral mastectomy warrant further investigation. Theoretically, exposure to radiation could induce the onset of secondary cancer; therefore, imaging and treatments that use radiation should be avoided as much as possible. As a method to follow-up LFS, routine cancer surveillance comprising whole-body MRI scan, brain MRI scan, breast MRI scan, and abdominal ultrasonography (US) should be performed immediately after the diagnosis. However, the effectiveness of this surveillance is unknown, and there are problems, such as adverse events associated with a high rate of false positives, overdiagnosis, and sedation used during imaging as well as negative psychological impact. The detection rate of cancer through cancer surveillance is extremely high. Many cases are detected at an early stage, and treatments are low intensity; thus, cancer surveillance could contribute to an improvement in QOL, or at least, a reduction in complications associated with treatment. With the widespread use of genomic medicine, the diagnosis of LFS is unavoidable, and a comprehensive medical care system for LFS is necessary. Therefore, clinical trials that verify the feasibility and effectiveness of the program, comprising LFS registry, genetic counseling, and cancer surveillance, need to be prepared.

Results from London Regional Clinical Genetics services over a 5-year period on germline TP53 testing in women diagnosed with breast cancer at <30 years

BACKGROUND

The most common cancer diagnosed in germline TP53 pathogenic variant (PV) carriers is premenopausal breast cancer. An increased rate of breast tumour HER2 positivity has been reported in this group. Screening for breast/other cancers is recommended in PV carriers.

OBJECTIVES

1. To assess the frequency of germline TP53 PVs reported diagnostically in women with breast cancer at <30 years of age.2. To evaluate the impact of personal/family history and HER2 status on the likelihood of germline TP53 pathogenic/likely pathogenic variant (PV/LPV) identification.

METHODS

Genetic test results from patients undergoing diagnostic germline TP53 tests between 2012 and 2017 in the four London Regional Clinical Genetics Services were reviewed. Clinical/pathology data and family history were extracted from genetics files for women diagnosed with breast cancer at <30 years.

RESULTS

The overall germline TP53 PV/LPV variant detection rate was 9/270=3.3% in all women diagnosed with breast cancer at <30 years and 2/171=1.2% in those with no second/subsequent cancer diagnosis or family history of TP53-spectrum cancers. Breast cancers were significantly more likely to be HER2-positive in TP53 PV/LPV carriers than in non-carriers (p=0.00006).

CONCLUSIONS

Germline TP53 PVs/LPVs are uncommon among women diagnosed with breast cancer aged <30 years without other relevant personal or family cancer history but have an important clinical impact when identified.

Examining the etiology of early-onset breast cancer in the Canadian Partnership for Tomorrow's Health (CanPath)

PURPOSE

Breast cancer incidence among younger women (under age 50) has increased over the past 25 years, yet little is known about the etiology among this age group. The objective of this study was to investigate relationships between modifiable and non-modifiable risk factors and early-onset breast cancer among three prospective Canadian cohorts.

METHODS

A matched case-control study was conducted using data from Alberta's Tomorrow Project, BC Generations Project, and the Ontario Health Study. Participants diagnosed with breast cancer before age 50 were identified through provincial registries and matched to three control participants of similar age and follow-up. Conditional logistic regression was used to examine the association between factors and risk of early-onset breast cancer.

RESULTS

In total, 609 cases and 1,827 controls were included. A body mass index ≥ 30 kg/m² was associated with a lower risk of early-onset breast cancer (OR 0.65; 95% CI 0.47-0.90), while a waist circumference ≥ 88 cm was associated with an increased risk (OR 1.58; 95% CI 1.18-2.11). A reduced risk was found for women with ≥ 2 pregnancies (OR 0.76; 95% CI 0.59-0.99) and a first-degree family history of breast cancer was associated with an increased risk (OR 1.95; 95% CI 1.47-2.57).

CONCLUSIONS

In this study, measures of adiposity, pregnancy history, and familial history of breast cancer are important risk factors for early-onset breast cancer. Evidence was insufficient to conclude if smoking, alcohol intake, fruit and vegetable consumption, and physical activity are meaningful risk factors. The results of this study could inform targeted primary and secondary prevention for early-onset breast cancer.

TP53 germline mutations in the context of families with hereditary breast and ovarian cancer: a clinical challenge

PURPOSE

TP53germline (g) mutations, associated with the Li-Fraumeni syndrome (LFS), have rarely been reported in the context of hereditary breast and ovarian cancer (HBOC). The prevalence and cancer risks in this target group are unknown and counseling remains challenging. Notably an extensive high-risk surveillance program is implemented, which evokes substantial psychological discomfort. Emphasizing the lack of consensus about clinical implications, we aim to further characterize TP53g mutations in HBOC families.

METHODS

Next-generation sequencing was conducted on 1876 breast cancer (BC) patients who fulfilled the inclusion criteria for HBOC.

RESULTS

(Likely) pathogenic variants in TP53 gene were present in 0.6% of the BC cohort with higher occurrence in early onset BC < 36 years. (1.1%) and bilateral vs. unilateral BC (1.1% vs. 0.3%). Two out of eleven patients with a (likely) pathogenic TP53g variant (c.542G > A; c.375G > A) did not comply with classic LFS/Chompret criteria. Albeit located in the DNA-binding domain of the p53-protein and therefore revealing no difference to LFS-related variants, they only displayed a medium transactivity reduction constituting a retainment of wildtype-like anti-proliferative functionality.

CONCLUSION

Among our cohort of HBOC families, we were able to describe a clinical subgroup, which is distinct from the classic LFS-families. Strikingly, two families did not adhere to the LFS criteria, and functional analysis revealed a reduced impact on TP53 activity, which may suit to the attenuated phenotype. This is an approach that could be useful in developing individualized screening efforts for TP53g mutation carrier in HBOC families. Due to the low incidence, national/international cooperation is necessary to further explore clinical implications. This might allow providing directions for clinical recommendations in the future.

Genetic/Familial High-Risk Assessment: Breast, Ovarian, and Pancreatic, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology

The NCCN Guidelines for Genetic/Familial High-Risk Assessment: Breast, Ovarian, and Pancreatic focus primarily on assessment of pathogenic or likely pathogenic variants associated with increased risk of breast, ovarian, and pancreatic cancer and recommended approaches to genetic testing/counseling and management strategies in individuals with these pathogenic or likely pathogenic variants. This manuscript focuses on cancer risk and risk management for BRCA-related breast/ovarian cancer syndrome and Li-Fraumeni syndrome. Carriers of a BRCA1/2 pathogenic or likely pathogenic variant have an excessive risk for both breast and ovarian cancer that warrants consideration of more intensive screening and preventive strategies. There is also evidence that risks of prostate cancer and pancreatic cancer are elevated in these carriers. Li-Fraumeni syndrome is a highly penetrant cancer syndrome associated with a high lifetime risk for cancer, including soft tissue sarcomas, osteosarcomas, premenopausal breast cancer, colon cancer, gastric cancer, adrenocortical carcinoma, and brain tumors.

Mutation screening of germline TP53 mutations in high-risk Chinese breast cancer patients

BACKGROUND

Germline TP53 mutations are associated with Li-Fraumeni syndrome, a severe and rare hereditary cancer syndrome. Despite the rarity of germline TP53 mutations, the clinical implication for mutation carriers and their families is significant. The risk management of TP53 germline mutation carriers is more stringent than BRCA carriers, and radiotherapy should be avoided when possible.

METHODS

TP53 gene mutation screening was performed in 2538 Chinese breast cancer patients who tested negative for BRCA mutations.

RESULTS

Twenty TP53 mutations were identified with high next-generation sequencing concerning for germline mutations in Chinese breast cancer families. The majorities of the TP53 carriers had early-onset, hormone receptor-positive breast cancer, and had strong family history of cancer. Among all, 11 patients carried a germline mutation and 6 of which were likely de novo germline mutations. In addition, 1 case was suspected to be induced by chemotherapy or radiation, as this patient had no significant family history of cancer and aberrant clonal expansion can commonly include TP53 mutations. Furthermore, we have identified one mosaic LFS case. Two novel mutations (c.524_547dup and c.529_546del) were identified in patients with early-onset.

CONCLUSIONS

In view of the high lifetime risk of malignancy, identification of patients with germline TP53 mutations are important for clinicians to aid in accurate risk assessment and offer surveillance for patients and their families.

TP53 germline mutation testing in early-onset breast cancer: findings from a nationwide cohort

Early-onset breast cancer may be due to Li-Fraumeni Syndrome (LFS). Current national and international guidelines recommend that TP53 genetic testing should be considered for women with breast cancer diagnosed before the age of 31 years. However, large studies investigating TP53 mutation prevalence in this population are scarce. We collected nationwide laboratory records for all young breast cancer patients tested for TP53 mutations in the Netherlands. Between 2005 and 2016, 370 women diagnosed with breast cancer younger than 30 years of age were tested for TP53 germline mutations, and eight (2.2%) were found to carry a (likely) pathogenic TP53 sequence variant. Among BRCA1/BRCA2 mutation negative women without a family history suggestive of LFS or a personal history of multiple LFS-related tumours, the TP53 mutation frequency was < 1% (2/233). Taking into consideration that TP53 mutation prevalence was comparable or even higher in some studies selecting patients with breast cancer onset at older ages or HER2-positive breast cancers, raises the question of whether a very early age of onset is an appropriate single TP53 genetic testing criterion.

Genetic counselling of young women with breast cancer for Li-Fraumeni syndrome: a nationwide survey on the experiences and attitudes of genetics professionals

Germline TP53 mutations are associated with an increased risk of early-onset breast cancer. Traditionally, it was not standard practice to offer TP53 genetic testing due to the low mutation detection rate and limited options regarding preventive screening. Recent guidelines recommend that all women diagnosed with breast cancer before the age of 31, irrespective of family history, should be offered TP53 genetic testing. This study aims to gain more knowledge on the attitudes and experiences among genetics professionals regarding the timing and content of genetic counselling of young breast cancer patients for Li–Fraumeni syndrome (LFS). We conducted a nationwide online survey among genetics professionals who provide cancer genetic counselling in the Netherlands. Fifty-seven professionals completed the questionnaire (response rate overall 54%, clinical geneticists 70%). Most respondents reported that they discuss the option of TP53 genetic testing—simultaneously with BRCA 1/2—during the initial counselling visit, especially in case of referral for treatment-focused genetic counselling. There was a general consensus about ten information items that should be discussed during counselling. Sixty-one percent of genetics professionals did not encounter difficulties in providing genetic counselling for LFS, but a substantial minority (29%) did. This study offers valuable insight, which will be useful for clinical practice. Studies which address young breast cancer patients’ attitudes and preferences regarding the timing and content of counselling are warranted to further determine the most appropriate genetic counselling strategy for these women.

Current review of TP53 pathogenic germline variants in breast cancer patients outside Li-Fraumeni syndrome

Pathogenic germline variants in TP53 predispose carriers to the multi-cancer Li-Fraumeni syndrome (LFS). Widespread multigene panel testing is identifying TP53 pathogenic variants in breast cancer patients outside the strict clinical criteria recommended for LFS testing. We aimed to assess frequency and clinical implications of TP53 pathogenic variants in breast cancer cohorts ascertained outside LFS. Classification of TP53 germline variants reported in 59 breast cancer studies, and publicly available population control sets was reviewed and identified evidence for misclassification of variants. TP53 pathogenic variant frequency was determined for: breast cancer studies grouped by ascertainment characteristics; breast cancer cohorts undergoing panel testing; and population controls. Early age of breast cancer onset, regardless of family history or BRCA1/BRCA2 previous testing, had the highest pick-up rate for TP53 carriers. Patients at risk of hereditary breast cancer unselected for features of LFS carried TP53 pathogenic variants at a frequency comparable to that of other non-BRCA1/2 breast cancer predisposing genes, and ∼threefold more than reported in population controls. These results have implications for the implementation of TP53 testing in broader clinical settings, and suggest urgent need to investigate cancer risks associated with TP53 pathogenic variants in individuals outside the LFS spectrum.

Genomic Disparities in Breast Cancer Among Latinas

BACKGROUND

Breast cancer is the most common cancer diagnosed among Latinas in the United States and the leading cause of cancer-related death among this population. Latinas tend to be diagnosed at a later stage and have worse prognostic features than their non-Hispanic white counterparts. Genetic and genomic factors may contribute to observed breast cancer health disparities in Latinas.

METHODS

We provide a landscape of our current understanding and the existing gaps that need to be filled across the cancer prevention and control continuum.

RESULTS

We summarize available data on mutations in high and moderate penetrance genes for inherited risk of breast cancer and the associated literature on disparities in awareness of and uptake of genetic counseling and testing in Latina populations. We also discuss common genetic polymorphisms and risk of breast cancer in Latinas. In the treatment setting, we examine tumor genomics and pharmacogenomics in Latina patients with breast cancer.

CONCLUSIONS

As the US population continues to diversify, extending genetic and genomic research into this underserved and understudied population is critical. By understanding the risk of breast cancer among ethnically diverse populations, we will be better positioned to make treatment advancements for earlier stages of cancer, identify more effective and ideally less toxic treatment regimens, and increase rates of survival.

Prevalence of the TP53 p.R337H mutation in breast cancer patients in Brazil

Germline TP53 mutations predispose individuals to multiple cancers and are associated with Li-Fraumeni/Li-Fraumeni-Like Syndromes (LFS/LFL). The founder mutation TP53 p.R337H is detected in 0.3% of the general population in southern Brazil. This mutation is associated with an increased risk of childhood adrenal cortical carcinoma (ACC) but is also common in Brazilian LFS/LFL families. Breast Cancer (BC) is one of the most common cancers diagnosed in TP53 mutation carriers. We have assessed the prevalence of p.R337H in two groups: (1) 59 BC affected women with a familial history (FH) suggestive of hereditary cancer syndrome but no LFS/LFL features; (2) 815 BC affected women unselected for cancer FH, diagnosed with BC at or before age 45 or at age 55 or older. Among group 1 and group 2 patients, 2/59 (3.4%, CI95%: 0.4%-11.7%) and 70/815 (8.6%, CI95%: 6.8%-10.7%), respectively, were p.R337H carriers in the germline. The prevalence of p.R337H was higher in women diagnosed with BC at or before age 45 (12.1%, CI95%: 9.1%-15.8%) than at age 55 or older (5.1%, CI95%: 3.2%-7.7%), p<0.001). The Brazilian founder p.R337H haplotype was detected in all carriers analysed. These results suggest that inheritance of p.R337H may significantly contribute to the high incidence of BC in Brazil, in addition to its recently demonstrated impact on the risk of childhood ACC.

Genetic evaluation based on family history and Her2 status correctly identifies TP53 mutations in very early onset breast cancer cases

Currently, hereditary breast cancer is being attributed to more than 20 genes of differing penetrance. Although BRCA1 and BRCA2 are still the genes of reference for breast cancer susceptibility, extreme breast cancer phenotypes may be the result of deleterious alleles of other genes. Here, we report three families with early-onset breast cancer that were initially referred for BRCA1/BRCA2 genetic testing. They were diagnosed with breast cancer at an extraordinarily early age. On the basis of their extensive family history, which included multiple cancer types, and their Her2 status, they were suspected for Li-Fraumeni syndrome. Indeed, all three probands were found to harbor TP53 tumor suppressor gene mutations. These included p.C275X, described here for the first time, as well as p.R213X and p.Y220C, which have been described in the past. Our conclusion is that decisions on genetic analysis for inherited early onset breast cancer should always be based on detailed pedigree information, combined with Her2 status.

The impact of next generation sequencing on the analysis of breast cancer susceptibility: a role for extremely rare genetic variation?

Women with a family history of breast cancer have an approximately twofold elevated risk of the disease. Even though an array of genes has been associated with breast cancer risk the past two decades, variants within these genes jointly explain at most 40% of this familial risk. Many explanations for this 'missing heritability' have been proposed, including the existence of many very rare variants, interactions between genetic and environmental factors and structural genetic variation. In this review, we discuss how next generation sequencing will teach us more about the genetic architecture of breast cancer, with a specific focus on very rare genetic variants. While such variants potentially explain a substantial proportion of familial breast cancer, assessing the breast cancer risks conferred by them remains challenging, even if this risk is relatively high. To assess more moderate risks, epidemiological approaches will require very large patient cohorts to be genotyped for the variant, only achievable through international collaboration. How well we will be able to eventually resolve the missing heritability for breast cancer in a clinically meaningful way crucially depends on the underlying complexity of the genetic architecture.

Prospective observational study of breast cancer treatment outcomes for UK women aged 18-40 years at diagnosis: the POSH study

BACKGROUND

Breast cancer at a young age is associated with poor prognosis. The Prospective Study of Outcomes in Sporadic and Hereditary Breast Cancer (POSH) was designed to investigate factors affecting prognosis in this patient group.

METHODS

Between 2000 and 2008, 2956 patients aged 40 years or younger were recruited to a UK multicenter prospective observational cohort study (POSH). Details of tumor pathology, disease stage, treatment received, and outcome were recorded. Overall survival (OS) and distant disease-free interval (DDFI) were assessed using Kaplan-Meier curves. All statistical tests were two-sided.

RESULTS

Median age of patients was 36 years. Median tumor diameter was 22 mm, and 50% of patients had positive lymph nodes; 59% of tumors were grade 3, 33.7% were estrogen receptor (ER) negative, and 24% were human epidermal growth factor receptor 2 (HER2) positive. Five-year OS was higher for patients with ER-positive than ER-negative tumors (85.0%, 95% confidence interval [CI] = 83.2% to 86.7% vs 75.7%, 95% CI = 72.8% to 78.4%; P < .001), but by eight years, survival was almost equal. The eight-year OS of patients with ER-positive tumors was similar to that of patients with ER-negative tumors in both HER2-positive and HER2-negative subgroups. The flexible parametric survival model for OS shows that the risk of death increases steadily over time for patients with ER-positive tumors in contrast to patients with ER-negative tumors, where risk of death peaked at two years.

CONCLUSIONS

These results confirm the increased frequency of ER-negative tumors and early relapse in young patients and also demonstrate the equally poor longer-term outlook of young patients who have ER-positive tumors with HER2-negative or -positive disease.

Routine TP53 testing for breast cancer under age 30: ready for prime time?

It is well known that early-onset breast cancer may be due to an inherited predisposition. When evaluating women diagnosed with breast cancer under age 30, two important syndromes are typically considered: Hereditary Breast and Ovarian Cancer Syndrome and Li-Fraumeni syndrome. Many women are offered genetic testing for mutations in the BRCA1 and BRCA2 genes; however, few are offered genetic testing for mutations in the TP53 gene. There is a concern that overly restrictive testing of TP53 may fail to recognize families with Li-Fraumeni syndrome. We reviewed the genetic test results and family histories of all women with early-onset breast cancer who had genetic testing of the TP53 gene at the Toronto Hospital for Sick Children. Of the 28 women tested, six (33.3 %) had a mutation in the TP53 gene; a mutation was found in 7.7 % of women who did not meet current criteria for Li-Fraumeni syndrome. By reviewing similar data published between 2000 and 2011, we estimate that 5-8 % of women diagnosed with early-onset breast cancer, and who have a negative family history, may have a mutation in the TP53 gene. Given the potential benefits versus harms of this testing, we discuss the option of simultaneous testing of all three genes (BRCA1, BRCA2, and TP53) for women diagnosed with breast cancer before age 30.

No evidence for breast cancer susceptibility associated with variants of BRD7, a component of p53 and BRCA1 pathways

BRD7 (bromodomain 7), a subunit of poly-bromo-associated BRG1-associated factor (PBAF)-specific Swi/Snf chromatin remodeling complexes, has been proposed as a tumour suppressor protein following its identification as an important component of both functional p53 and BRCA1 (breast cancer 1, early onset) pathways. As low BRD7 expression levels have been linked to p53-wild-type breast tumour cells, we hypothesized an implication of BRD7 germline alterations in the pathogenesis of hereditary breast cancer similar to that of TP53 in Li-Fraumeni syndrome. We performed sequence analysis of the BRD7 gene on 61 high-risk individuals with hereditary or very-early-onset breast cancer and 100 healthy controls. Four potentially disease-causing single-nucleotide alterations were detected within the cohort of breast cancer patients (one listed as a rare single-nucleotide polymorphism (SNP) in the NCBI (National Center for Biotechnology Information) SNP database). Two of the detected variants were also each found once within the control collective. Segregation analysis on both families of those carrying the remaining two variants revealed segregation of these BRD7 alterations independent of breast cancer. In conclusion, it seems that the BRD7 variants we detected represent rare polymorphisms and mainly rule out BRD7 as a frequent high-penetrance breast cancer susceptibility gene. However, further analyses in larger cohorts of women with hereditary breast cancer should clarify the role of BRD7 in breast cancer predisposition.

Prevalence of germline TP53 mutations in HER2+ breast cancer patients

Breast cancer is the most frequent tumor in Li-Fraumeni syndrome (LFS), a rare inherited cancer syndrome associated with germline mutations in the TP53 gene. Recent data show that breast cancer in germline TP53 mutation carriers is commonly HER2+ (63-83 %). We assessed the prevalence of germline TP53 mutations in a cohort of women with HER2+ breast cancer diagnosed age ≤50 years. We identified blood specimens from 213 women with primary invasive HER2+ breast cancer age ≤50 years from a single center. Exon grouping analysis sequencing and multiplex ligation-dependent probe amplification techniques were used to screen for germline TP53 mutations. Among 213 women with HER2+ breast cancer age ≤50 years, 3 (ages at diagnosis 23, 32, 44 years) were found to carry a TP53 mutation (1.4 %, 95 % CI 0.3-4.1 %). ER/PR status was not uniform. Two TP53 carriers met Chompret criteria for LFS; none met classic LFS criteria. Although two-thirds of breast cancers in women with TP53 mutations are HER2+, we observed a low prevalence of germline TP53 mutations among unselected young women with HER2+ breast cancer. Given the potential clinical impact, consideration of germline TP53 testing should be given to young women with HER2+ breast cancer, especially if family cancer history is notable.

Comprehensive analysis of BRCA1, BRCA2 and TP53 germline mutation and tumor characterization: a portrait of early-onset breast cancer in Brazil

Germline mutations in BRCA1, BRCA2 and TP53 genes have been identified as one of the most important disease-causing issues in young breast cancer patients worldwide. The specific defective biological processes that trigger germline mutation-associated and -negative tumors remain unclear. To delineate an initial portrait of Brazilian early-onset breast cancer, we performed an investigation combining both germline and tumor analysis. Germline screening of the BRCA1, BRCA2, CHEK2 (c.1100delC) and TP53 genes was performed in 54 unrelated patients <35 y; their tumors were investigated with respect to transcriptional and genomic profiles as well as hormonal receptors and HER2 expression/amplification. Germline mutations were detected in 12 out of 54 patients (22%) [7 in BRCA1 (13%), 4 in BRCA2 (7%) and one in TP53 (2%) gene]. A cancer familial history was present in 31.4% of the unrelated patients, from them 43.7% were carriers for germline mutation (37.5% in BRCA1 and in 6.2% in the BRCA2 genes). Fifty percent of the unrelated patients with hormone receptor-negative tumors carried BRCA1 mutations, percentage increasing to 83% in cases with familial history of cancer. Over-representation of DNA damage-, cellular and cell cycle-related processes was detected in the up-regulated genes of BRCA1/2-associated tumors, whereas cell and embryo development-related processes were over-represented in the up-regulated genes of BRCA1/2-negative tumors, suggesting distinct mechanisms driving the tumorigenesis. An initial portrait of the early-onset breast cancer patients in Brazil was generated pointing out that hormone receptor-negative tumors and positive familial history are two major risk factors for detection of a BRCA1 germline mutation. Additionally, the data revealed molecular factors that potentially trigger the tumor development in young patients.

Prevalence of TP53 germ line mutations in young Pakistani breast cancer patients

Women from Pakistan and India are more often diagnosed with early-onset breast cancer than Caucasian women. Given that only 12% of Pakistani women diagnosed with breast cancer at or before 30 years of age have previously been shown to harbor germ line mutations in the breast cancer susceptibility genes BRCA1 and BRCA2, the genetic causes of the majority of early-onset cases are unexplained. Since germ line mutations in the tumor suppressor gene TP53 predispose women to early-onset breast cancer, we assessed the prevalence of TP53 mutations in 105 early-onset breast cancer patients from Pakistan, who had previously been found to be negative for BRCA1 and BRCA2 germ line mutations. The patient group included 67 women diagnosed with early-onset breast cancer at or before age 30 with no family history of breast or ovarian cancer (EO30NFH group) and 38 women diagnosed with breast cancer at or before age 40 with one or more first- or second-degree relatives with breast or ovarian cancer (EO40FH group). Mutation analysis of the complete TP53 coding region was performed using denaturing high-performance liquid chromatography analysis, followed by DNA sequencing of variant fragments. One deleterious mutation, c.499-500delCA in exon 5, was identified in the 105 breast cancer patients (1%). This mutation is novel in the germ line and has not been described in other populations. It was detected in a 28-year-old patient with no family history of breast or ovarian cancer. This mutation is rare as it was not detected in additional 157 recently recruited non-BRCA1 and non-BRCA2-associated early-onset breast cancer patients. Our findings show that TP53 mutations may account for a minimal portion of early-onset breast cancer in Pakistan.

The tip of the iceberg: a countercurrents series

In February 2012, Ambry Genetics, a testing company based in Aliso Viejo, California, began to offer the BreastNext genetic test to women with earlyonset or familial breast cancer [...]

Breast cancer in young women

About one in 300 women will be diagnosed with breast cancer before the age of 40. Advances in screening have not had an impact on mortality in women who are too young to be candidates for screening. Risk factors for early breast cancer include a lean body habitus and recent use of an oral contraceptive. Breast cancers in very young women are typically aggressive, in part owing to the over-representation of high-grade, triple-negative tumours, but young age is an independent negative predictor of cancer-specific survival. Very early age-of-onset also correlates strongly with the risk of local recurrence and with the odds of contralateral breast cancer. Given the high risks of local and distant recurrence in young women with invasive breast cancer, most (if not all) young patients are candidates for chemotherapy. It is hoped that by increasing breast cancer awareness, the proportion of invasive breast cancers that are diagnosed at 2.0 cm or smaller will increase and that this will lead to a reduction in mortality.

Late onset Li-Fraumeni Syndrome with bilateral breast cancer and other malignancies: case report and review of the literature

Background

Li-Fraumeni-Syndrome (LFS) is an autosomal-dominant, inherited tumour predisposition syndrome associated with heterozygous germline mutations in the TP53 gene. Patients with LFS are at a high risk to develop early-onset breast cancer and multiple malignancies, among which sarcomas are the most common. A high incidence of childhood tumours and close to 100% penetrance has been described. Knowledge of the genetic status of the TP53 gene in these patients is critical not only due to the increased risk of malignancies, but also because of the therapeutic implications, since a higher rate of radiation-induced secondary tumours in these patients has been observed.

Case report

We report a patient with LFS harbouring heterozygous, pathogenic TP53 germline mutation, who was affected by four synchronous malignancies at the age of 40: a myxofibrosarcoma of the right upper arm, bilateral breast cancer and a periadrenal liposarcoma. Radiological treatments and a surveillance program were adjusted according to recommendations for LFS patients.

Conclusion

Management of tumour treatment of patients with LFS is different to the general population because of their risk for secondary cancers in the radiation field. Screening procedures should take a possibly elevated risk for radiation induced cancer into account.

Apparently "BRCA-related" breast and ovarian cancer patient with germline TP53 mutation

Germline TP53 gene mutations are associated with complex cancer predisposition syndrome, the Li--Fraumeni syndrome, and are not as rare as were previously thought. Currently, the identification of Li--Fraumeni syndrome is mostly based on a conformance to descriptive criteria, which recently were amended to include wider spectrum of malignancies. The presence of very young age-onset breast cancers in TP53 mutations families is a feature that overlaps with hereditary breast/ovarian cancer families with BRCA1/2 genes mutations. Peri-diagnostic germline TP53 testing results in breast cancer patients can significantly affect surgical and adjuvant radiotherapy choices. The aim of this case report is to emphasize the importance of peri-diagnostic germline TP53 molecular testing in patients with early-onset breast cancer and its effect on the management and outcome of the disease. We present the apparent BRCA1-related, although mutation negative, breast and ovarian cancer patient who subsequently was confirmed to be TP53 c.817C>T (p.R273C) mutation carrier and discuss the importance of peri-diagnostic oncogenetic TP53 testing in early breast cancer cases. Histopathology and genetic modifiers (MDM2 SNP309G; TP53 R72P, PIN3) data are also addressed.

Breast cancer in young women

Although uncommon, breast cancer in young women is worthy of special attention due to the unique and complex issues that are raised. This article reviews specific challenges associated with the care of younger breast cancer patients, which include fertility preservation, management of inherited breast cancer syndromes, maintenance of bone health, secondary prevention, and attention to psychosocial issues.