Hereditary Pancreatic Cancer: A Retrospective Single-Center Study of 5143 Italian Families with History of BRCA-Related Malignancies

Germline landscape of BRCAs by 7-site collaborations as a BRCA consortium in Turkey

BRCA1/2 mutations play a significant role in cancer pathogenesis and predisposition particularly in breast, ovarian and prostate cancers. Thus, germline analysis of BRCA1 and BRCA2 is essential for clinical management strategies aiming at the identification of recurrent and novel mutations that could be used as a first screening approach. We analyzed germline variants of BRCA1/2 genes for 2168 individuals who had cancer diagnosis or high risk assessment due to BRCAs related cancers, referred to 10 health care centers distributed across 7 regions covering the Turkish landscape. Overall, 68 and 157 distinct mutations were identified in BRCA1 and BRCA2, respectively. Twenty-two novel variants were reported from both genes while BRCA2 showed higher mutational heterogeneity. We herein report the collective data as BRCA Turkish consortium that confirm the molecular heterogeneity in BRCAs among Turkish population, and also as the first study presenting the both geographical, demographical and gene based landscape of all recurrent and novel mutations which some might be a founder effect in comparison to global databases. This wider perspective leads to the most accurate variant interpretations which pave the way for the more precise and efficient management affecting the clinical and molecular aspects.

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A similar percentage of clinically unaffected individuals were also identified with potentially pathogenic variants.

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Based on the geographic examinations, Eastern Anatolian and the Mediterranean region had the lowest positivity rates.

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The Southeastern Anatolian region showed the lowest density of both patients and clinically relevant genetic changes.

Cancer Predisposition Genes in Adolescents and Young Adults (AYAs): a Review Paper from the Italian AYA Working Group

PURPOSE OF REVIEW

The present narrative systematic review summarizes current knowledge on germline gene mutations predisposing to solid tumors in adolescents and young adults (AYAs).

RECENT FINDINGS

AYAs with cancer represent a particular group of patients with specific challenging characteristics and yet unmet needs. A significant percentage of AYA patients carry pathogenic or likely pathogenic variants (PV/LPVs) in cancer predisposition genes. Nevertheless, knowledge on spectrum, frequency, and clinical implications of germline variants in AYAs with solid tumors is limited. The identification of PV/LPV in AYA is especially critical given the need for appropriate communicative strategies, risk of second primary cancers, need for personalized long-term surveillance, potential reproductive implications, and cascade testing of at-risk family members. Moreover, these gene alterations may potentially provide novel biomarkers and therapeutic targets that are lacking in AYA patients. Among young adults with early-onset phenotypes of malignancies typically presenting at later ages, the increased prevalence of germline PV/LPVs supports a role for genetic counseling and testing irrespective of tumor type.

Pancreatic Cancer with Mutation in BRCA1/2, MLH1, and APC Genes: Phenotype Correlation and Detection of a Novel Germline BRCA2 Mutation

Pancreatic ductal adenocarcinoma (PDAC) is the seventh leading cause of cancer death worldwide; most of cases are sporadic, however about 5% to 10% report a hereditary predisposition. Several hereditary syndromes have been associated with familial pancreatic cancer (FPC) onset, including hereditary breast and ovarian cancer syndrome (HBOC), Lynch syndrome (LS), Familial atypical multiple mole melanoma (FAMMM), Familial adenomatous polyposis (FAP), Li-Fraumeni syndrome (LFS), Peutz-Jeghers syndrome (PJS), and Hereditary pancreatitis (HP).The aim of this study was to determine the mutational status of a cohort of 56 HBOC families, 7 LS families, 3 FAP and FAMMM families, and 1 LFS family with at least one case of PDAC. Mutation analysis of BRCA1/2, ATM, CHEK2, PALB2, RAD51C, RAD51D, NBN, CDH1, TP53, MLH1, MSH2, MSH6, and PMS2 genes, showedmutation in BRCA1/2, MLH1, and APC genes. We founda high mutation rate in patients belong HBOC and LS families, with a percentage of 28.6% in both syndromes and prevalence in HBOC of BRCA2 mutations with one case of double mutation in BRCA2 gene. In FAP family, we found a pathogenic mutation in APC gene in 1/3 families. We observed an early onset of PDAC and a lower survival in PDAC patients belonging to mutated families, while no evidence of possible pancreatic cancer cluster regions was found. Moreover, we identified a novel BRCA2 germline mutation, c.5511delT (p.Phe1837LeufsX3), not reported in any database, that segregated with disease in HBOC patients. Mutational analysis was extended to family membersof mutated patients, both healthy and cancer affected, which revealed 23 unaffected family members that inherited the proband's mutation. Although correlative by its nature, the presence of a BRCA mutation in PDAC patients may have benefits in terms of optimized treatment and longer outcome.

Clinical Characteristics of Patients With Pancreatic Cancer and Pathogenic ATM Alterations

The Ataxia-Telangiesctasia, mutated (ATM) gene is involved in a number of DNA damage repair pathways and confers an increased risk for pancreatic ductal adenocarcinoma (PDAC). In this retrospective study, we identified and profiled 22 patients with PDAC and a known somatic or germline pathogenic ATM alteration (case patients). These patients were matched 2:1 by age, stage, and year at diagnosis to patients with PDAC without known ATM alterations. The median overall survival in patients with ATM alterations was 40.2 months compared with 15.5 months in the control population (hazard ratio = 0.14, 95% confidence interval = 0.04 to 0.47, 2-sided P = .001). In multivariable analysis, these findings persisted after adjustment for receipt of platinum therapy and Eastern Cooperative Oncology Group status. These findings suggest that pathogenic ATM alterations may be prognostic for improved outcomes in patients with pancreatic cancer.

Germinal BRCA1-2 pathogenic variants (gBRCA1-2pv) and pancreatic cancer: epidemiology of an Italian patient cohort

OBJECTIVE

Germline BRCA1-2 pathogenic variants (gBRCApv) increase the risk of pancreatic cancer and predict for response to platinating agents and poly(ADP-ribose) polymerase inhibitors. Data on worldwide gBRCApv incidence among pancreatic ductal adenocarcinoma (PDAC) patients are sparse and describe a remarkable geographic heterogeneity. The aim of this study is to analyze the epidemiology of gBRCApv in Italian patients.

MATERIALS AND METHODS

Patients of any age with pancreatic adenocarcinoma, screened within 3 months from diagnosis for gBRCApv in Italian oncologic centers systematically performing tests without any selection. For the purposes of our analysis, breast, ovarian, pancreas, and prostate cancer in a patient's family history was considered as potentially BRCA-associated. Patients or disease characteristics were examined using the χ2 test or Fisher's exact test for qualitative variables and the Student's t-test or Mann-Whitney test for continuous variables, as appropriate.

RESULTS

Between June 2015 and May 2020, 939 patients were tested by 14 Italian centers; 492 (52%) males, median age 62 years (range 28-87), 569 (61%) metastatic, 273 (29%) with a family history of potentially BRCA-associated cancers. gBRCA1-2pv were found in 76 patients (8.1%; 9.1% in metastatic; 6.4% in non-metastatic). The gBRCA2/gBRCA1 ratio was 5.4 : 1. Patients with gBRCApv were younger compared with wild-type (59 versus 62 years, P = 0.01). The gBRCApv rate was 17.1% among patients <40 years old, 10.4% among patients 41-50 years old, 9.2% among patients 51-60 years old, 6.7% among patients aged 61-70 years, and 6.2% among patients >70 years old (none out of 94 patients >73 years old). gBRCApv frequency in 845 patients <74 years old was 9%. Patients with/without a family history of potentially BRCA-associated tumors had 14%/6% mutations.

CONCLUSION

Based on our findings of a gBRCApv incidence higher than expected in a real-life series of Italian patients with incident PDAC, we recommend screening all PDAC patients <74 years old, regardless of family history and stage, due to the therapeutic implications and cancer risk prevention in patients' relatives.

Prevalence of mutations in BRCA and MMR genes in patients affected with hereditary endometrial cancer

Endometrial cancer (EC) is the fifth most common cancer in women from developed countries, accounting for 4.8% of new cases and 2.1% of deaths. The genetic basis for the familial risk of endometrial cancer has not been completely defined. Mostly, hereditary EC is part of two syndromes as Lynch syndrome (LS) and Hereditary Breast and Ovarian Cancer syndrome (HBOC). LS is the prototypical hereditary cancer syndrome in EC and accounts for 2-6% of all endometrial cancers. This disease is caused by autosomal dominant mutations in DNA mismatch repair (MMR) genes. Patients carrying a germline mutation in one of the MMR genes have a cumulative lifetime risk to develop EC of 20-70%. HBOC is an autosomal dominantly inherited disease, which mostly predisposes to breast and ovarian cancers, but it can be also associated with other malignancies. HBOC results from germline mutations in BRCA1/2 genes. The aim of this study was to determine the mutational status of a cohort of 40 EC patients, 19 belonging to families with LS and 21 to HBOC. Mutation analysis of MLH1, MSH2, BRCA1 and BRCA2 genes showed pathogenic variants in 17/40 (42.5%) patients. Out of 19 patients belonging to LS families, 8 (42.1%) showed a pathogenic variant. Out of 21 patients belonging to HBOC families, 9 (42.8%) showed a pathogenic variant. 1/21 (4.8%) patient report 1 variant of unknown significance (UV), c.599 C > T (p.T200I), in BRCA2. Moreover, in 1/21 (4.8%) patient we identified a novel missense variant in BRCA2, c.9541A > T (p.Met3181Leu). Mutational analysis was extended to family members, both healthy and cancer affected, of mutated patients; all the tested relatives affected with cancer displayed the pathogenic variant. Our data suggest that patients with hereditary EC have a high percentage of mutations in the LS and HBOC main susceptibility genes; therefore, the surveillance for EC, already indicated in LS patients, should also be recommended for patients with HBOC.

Five Italian Families with Two Mutations in BRCA Genes

Double heterozygosity (DH) in BRCA1 and BRCA2 genes and double mutation (DM) in BRCA1 or BRCA2 are extremely rare events in the general population, and few cases have been reported worldwide so far. Here, we describe five probands, all women, with breast and/or ovarian cancer and their families. Particularly, we identified two probands with DH in the BRCA1/2 genes with a frequency of 0.3% and three probands with DM in the BRCA2 gene with a frequency of 0.5%. The DH BRCA1 c.547+2T>A (IVS8+2T>A)/BRCA2 c.2830A>T (p.Lys944Ter) and BRCA1 c.3752_3755GTCT (p.Ser1253fs)/BRCA2 c.425+2T>C (IVS4+2T>C) have not been described together so far. The DM in BRCA2, c.631G>A (p.Val211Ile) and c.7008-2A>T (IVS13-2A>T), found in three unrelated probands, was previously reported in further unrelated patients. Due to its peculiarity, it is likely that both pathogenic variants descend from a common ancestor and, therefore, are founder mutations. Interestingly, analyzing the tumor types occurring in DH and DM families, we observed ovarian cancer only in DH families, probably due to the presence in DH patients of BRCA1 pathogenic variants, which predispose one more to ovarian cancer onset. Furthermore, male breast cancer and pancreatic cancer ensued in families with DM but not with DH. These data confirm that BRCA2 pathogenic variants have greater penetrance to develop breast cancer in men and are associated with an increased risk of pancreatic cancer.

BRCA in Gastrointestinal Cancers: Current Treatments and Future Perspectives

A strong association between pancreatic cancer and BRCA1 and BRCA2 mutations is documented. Based on promising results of breast and ovarian cancers, several clinical trials with poly (ADP-ribose) polymerase inhibitors (PARPi) are ongoing for gastrointestinal (GI) malignancies, especially for pancreatic cancer. Indeed, the POLO trial results provide promising and awaited changes for the pancreatic cancer therapeutic landscape. Contrariwise, for other gastrointestinal tumors, the rationale is currently only alleged. The role of BRCA mutation in gastrointestinal cancers is the subject of this review. In particular, we aim to provide the latest updates about novel therapeutic strategies that, exploiting DNA repair defects, promise to shape the future therapeutic scenario of GI cancers.

FoundationOne® CDx gene profiling in Japanese pancreatic ductal adenocarcinoma patients: a single-institution experience

PURPOSE

The aim of this study was to investigate the genetic mutation profiles of Japanese pancreatic ductal adenocarcinoma (PDAC) patients.

METHODS

Next-generation sequencing was performed using FoundationOne® CDx on 17 PDAC patients who were treated by surgical resection at Kyushu University Hospital between February 2016 and January 2019. The tumor mutational burden and microsatellite instability status were also assessed.

RESULTS

There were 16 patients (94%) with KRAS mutations, 13 (76%) with TP53 mutations, three (18%) with SMAD4 mutations, and one (6%) with a CDKN2A mutation. All patients had at least one pathogenic variant or a likely pathogenic variant. No patient had targeted therapies that matched with any clinical benefit according to FoundationOne® CDx. An unresectable PDAC patient with BRCA2-mutant disease was successfully treated by conversion surgery using platinum-based neoadjuvant chemotherapy.

CONCLUSIONS

Currently, FoundationOne® CDx might be difficult to use on PDAC patients, although further investigations with larger study populations are called for.

Secondary Prevention in Hereditary Breast and/or Ovarian Cancer Syndromes Other Than BRCA

BRCA1- and BRCA2-associated hereditary breast and ovarian cancer syndromes are among the best-known and most extensively studied hereditary cancer syndromes. Nevertheless, many patients who proved negative at BRCA genetic testing bring pathogenic mutations in other suppressor genes and oncogenes associated with hereditary breast and/or ovarian cancers. These genes include TP53 in Li-Fraumeni syndrome, PTEN in Cowden syndrome, mismatch repair (MMR) genes in Lynch syndrome, CDH1 in diffuse gastric cancer syndrome, STK11 in Peutz-Jeghers syndrome, and NF1 in neurofibromatosis type 1 syndrome. To these, several other genes can be added that act jointly with BRCA1 and BRCA2 in the double-strand break repair system, such as PALB2, ATM, CHEK2, NBN, BRIP1, RAD51C, and RAD51D. Management of primary and secondary cancer prevention in these hereditary cancer syndromes is crucial. In particular, secondary prevention by screening aims to discover precancerous lesions or cancers at their initial stages because early detection could allow for effective treatment and a full recovery. The present review aims to summarize the available literature and suggest proper screening strategies for hereditary breast and/or ovarian cancer syndromes other than BRCA.

BRCA Detection Rate in an Italian Cohort of Luminal Early-Onset and Triple-Negative Breast Cancer Patients without Family History: When Biology Overcomes Genealogy

NCCN Guidelines recommend BRCA genetic testing in individuals with a probability >5% of being a carrier. Nonetheless, the cost-effectiveness of testing individuals with no tumor family history is still debated, especially when BRCA testing is offered by the national health service. Our analysis evaluated the rate of BRCA pathogenic or likely-pathogenic variants in 159 triple-negative breast cancer (TNBC) patients diagnosed ≤60 years, and 109 luminal-like breast cancer (BC) patients diagnosed ≤35 without breast and/or ovarian family histories. In TNBC patients, BRCA mutation prevalence was 22.6% (21.4% BRCA1). Mutation prevalence was 64.2% ≤30 years, 31.8% in patients aged 31–40, 16.1% for those aged 41–50 and 7.9% in 51–60 s. A total of 40% of patients with estrogen receptors (ER) 1–9% were BRCA1 carriers. BRCA detection rate in early-onset BCs was 6.4% (4.6% BRCA2). Mutation prevalence was 0% between 0–25 years, 9% between 26–30 years and 6% between 31–35 years. In conclusion, BRCA testing is recommended in TNBC patients diagnosed ≤60 years, regardless of family cancer history or histotype, and by using immunohistochemical staining <10% for both ER and/PR. In luminal-like early-onset BC, a lower BRCA detection rate was observed, suggesting a role for other predisposing genes along with BRCA genetic testing.

Platinum response characteristics of patients with pancreatic ductal adenocarcinoma and a germline BRCA1, BRCA2 or PALB2 mutation

BACKGROUND

Retrospective studies suggest a survival benefit when platinum-based chemotherapy is administered to patients with pancreatic cancer harbouring a germline mutation in BRCA1, BRCA2 or PALB2 (mut-positive PDAC). However, the objective response rate (ORR) and real-world progression free survival (rwPFS) achieved with such treatment remain ill-defined.

METHODS

Twenty-six patients with advanced-stage mut-positive PDAC who had been treated with platinum-based therapy were matched by age, race and sex to 52 platinum-treated control PDAC patients. Responses to therapy were determined by RECIST v1.1, performed by blinded radiology review. Measured outcomes included ORR and rwPFS.

RESULTS

The ORR in mut-positive patients was 58% compared to 21% in the control group (p = 0.0022). There was no significant difference in ORR between platinum regimens in mut-positive patients (p = 0.814), whereas in control patients, the only observed responses were to FOLFIRINOX. rwPFS was 10.1 mo. for mut-positive patients and 6.9 mo. for controls (HR 0.43; 95% CI 0.25-0.74; 0.0068).

CONCLUSION

Mut-positive PDAC has a high ORR and prolonged rwPFS to platinum-based chemotherapy. These findings may have implications particularly in the neoadjuvant setting, and for future clinical trial design, and highlight the importance of early germline testing in patients with PDAC.