Purpose Germline mutations in the homologous recombination (HR) genes BRCA1, BRCA2, and PALB2 confer an increased risk for pancreatic ductal adenocarcinoma (PDAC). Tumors associated with mutations in HR genes are sensitive to DNA-damaging agents, such as platinum chemotherapies. We hypothesized that patients with PDAC with germline BRCA1, BRCA2, or PALB2 mutations may benefit preferentially from platinum-based chemotherapy. Materials and Methods Twenty-nine individuals with deleterious germline mutations in BRCA1, BRCA2, or PALB2 and a diagnosis of advanced PDAC (mut-positive) were matched 2:1 to patients who were noncarrier or untested (control) by age at diagnosis, year of diagnosis, stage, and sex. Patients were identified via one of two available databases at the University of Pennsylvania: the Basser Center for BRCA Registry or the University of Pennsylvania Electronic Medical Patient Record. Treatment history, including exposure to platinum-based chemotherapy, was ascertained. Primary objective was overall survival (OS). Results Patients who were mut-positive had an OS of 21.8 months; control patients had an OS of 8.1 months (hazard ratio [HR], 0.35; 95% CI, 0.2 to 0.62; P < .001). With platinum exposure, patients who were mut-positive had an undefined OS (median follow-up, 20.1 months), versus an OS of 15.5 months in the control patients (HR, 0.25; 95% CI, 0.1 to 0.61; P = .002). In patients not treated with platinum, there was no significant difference in OS between groups (HR, 0.54; 95% CI, 0.25 to 1.17; P = .12). When treated with platinum therapy, patients who were mut-positive had a 1-year OS of 94%, compared with a 1-year OS of 60% in control patients. Conclusion Platinum-based therapy may confer a survival benefit in patients with advanced PDAC who carry a deleterious germline BRCA1, BRCA2, or PALB2 mutation.

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PURPOSE Germline mutations in the homologous recombination genes BRCA1, BRCA2, and PALB2 confer an increased risk for pancreatic ductal adenocarcinoma (PDAC). Tumors associated with mutations in homologous recombination genes are sensitive to DNA-damaging agents. We retrospectively studied patients with resected PDAC and a pathogenic germline mutation in one of these three genes. The planned analyses included overall survival (OS) and changes therein when platinum chemotherapy was used in the perioperative setting. MATERIALS AND METHODS Thirty-two individuals with pathogenic germline mutations in BRCA1, BRCA2, or PALB2 and resected PDAC (mutation positive) were matched in a 1:2 fashion to patients who were noncarriers or untested (mutation negative) by age, year of diagnosis, stage, and sex. Patients were identified via one of two available databases at University of Pennsylvania: the Basser Center for BRCA Registry or the electronic medical record. The primary outcome was OS. RESULTS Patients in the mutation-positive group had a median OS (mOS) of 46.6 months; those in the mutation-negative group had an mOS of 23.2 months (hazard ratio [HR], 0.49; 95% CI, 0.27 to 0.88). With platinum exposure in the perioperative setting, mOS in the mutation-positive group had not yet been met versus a mOS of 23.1 months in the mutation-negative group (HR, 0.12; 95% CI, 0.01 to 1.00). When neither group was treated with platinum, there was no significant OS difference between groups (HR, 0.52; 95% CI 0.12 to 2.24). Patients in the mutation-positive group who received perioperative treatment with platinum had a trend toward improved mOS compared with those who did not (HR, 0.15; 95% CI, 0.02 to 1.23; P = .07). CONCLUSION Platinum-based chemotherapy may confer a survival benefit in patients with resected PDAC and a pathogenic germline BRCA1, BRCA2, or PALB2 mutation. Knowledge of a germline mutation may be important to determine best choice of perioperative chemotherapy.

PURPOSE Germline CDH1 pathogenic variants (PV) are associated with hereditary diffuse gastric cancer and lobular breast cancer. Although prevalence of CDH1 PV is low in the general population, detection of these variants is increasing with the growing use of multigene panel testing. Little is known about the experiences of individuals tested for CDH1 variants in the multigene panel testing era. METHODS Participants recruited from the Prospective Registry of Multiplex Testing completed a cross-sectional self-report survey regarding CDH1 genetic testing experiences, medical management, and psychosocial adaptation. RESULTS Discordance existed in interpretations of CDH1 results; 13.3% of cases had disagreements in variant classifications among commercial laboratories, and 21.4% had disagreements between participant self-report and ClinVar classification. Survey data were available from 57 individuals reporting either PV (n = 16) or variants of uncertain significance (VUS; n = 41). Those with PV were more likely than those with VUS to report receiving a recommendation for prophylactic gastrectomy, although only 40.0% of those with PV received this recommendation. Participants with VUS were less satisfied with their health care providers’ knowledge and reported less CDH1 knowledge, distress, and worry about discrimination. Participants with PV perceived greater breast cancer risks, but similar gastric cancer risks, as those with VUS. CONCLUSION Few individuals with CDH1 PV report receiving recommendations for prophylactic gastrectomy, and no differences in perceived gastric cancer risk were observed based on participants’ CDH1 results, suggesting serious unmet informational needs.