Germline Pathogenic Variants and Genetic Counseling by Ancestry in Patients With Epithelial Ovarian Cancer.

PURPOSE: To evaluate rates of germline pathogenic/likely pathogenic variants (PVs) and genetic counseling by ancestry in patients with epithelial ovarian cancer (EOC). METHODS: Patients with pathologically confirmed EOC who underwent clinical tumor-normal sequencing from January 1, 2015, to December 31, 2020, inclusive of germline analysis of ≥76 genes were included. Patients with newly identified PVs were referred for Clinical Genetics Service (CGS) counseling. Ancestry groups were defined using self-reported race/ethnicity and Ashkenazi Jewish (AJ) heritage. Genetic ancestry was inferred computationally using validated algorithms. Logistic regression models were built. RESULTS: Of 1,266 patients, self-reported ancestry (AJ, 17%; Asian, 10%; Black/African American, 5.4%; Hispanic, 6.2%; non-Hispanic White, 57%; other, 0.16%; unknown, 4.0%) correlated with genetic ancestry (AJ ancestry, 18%; admixed, 10%; African, 4%; East Asian [EAS], 6%; European, 56%; Native American, 0.2%; South Asian [SAS], 4%; unknown, 2%). Germline PVs were observed in 313 (25%) patients, including 195 (15%) with PVs in EOC-associated genes. Those with PVs were younger at diagnosis (59 v 62 years; P < .001) and more likely to have high-grade serous ovarian cancer (83% v 72%; P = .009). PV prevalence varied between ancestry groups (P < .001), with highest rates in the AJ (39.9%) and Asian (26.5%) groups and similar rates (>10%) across other ancestry groups. Use of genetic ancestry demonstrated similar findings and further characterized high rates of PV in EAS/SAS groups. Younger age, high-grade serous histology, and self-reported AJ or Asian ancestry were associated with PV in an EOC-associated gene. Rates of CGS counseling for newly identified PVs were high (80%) across ancestry groups. CONCLUSION: Rates of PV, particularly in EOC-associated genes, were high regardless of ancestry, with similar rates of counseling between groups, emphasizing the importance of universal genetic testing in all patients with EOC.

Attitudes toward preimplantation genetic testing and quality of life among individuals with hereditary diffuse gastric cancer syndrome.

BACKGROUND: Hereditary Diffuse Gastric Cancer (HDGC) syndrome is an autosomal dominant hereditary cancer predisposition associated with germline pathogenic/likely pathogenic variants in the CDH1 gene. Identifying early stage HDGC is difficult, and prophylactic measures can be effective in preventing incidence. Preimplantation Genetic Testing (PGT) can provide information about CDH1 variant status, HDGC risk, and limit familial transmission of CDH1 variants. To date, however, little is known about the attitudes of individuals with CDH1 variants towards PGT. METHODS: Given that little is known about the reproductive attitudes of individuals with HDGC, we recruited participants with CDH1 variants from a familial gastric cancer registry and administered a cross-sectional survey with open- and closed-ended response items. We assessed attitudes regarding PGT and the effect of HDGC on quality of life. RESULTS: Participants (n = 21) were predominantly partnered (61.9%), had a personal cancer history (71.4%), and had biological children (71.4%). Interest in learning about PGT was high; 66.7% of participants were interested in PGT and 90.5% approved of healthcare providers discussing PGT with individuals with CDH1 variants. Attitudes regarding personal use were varied. Among all participants, 35% would not, 25% were uncertain, and 40% would use PGT. Personal philosophy and preferences for family and reproduction were key factors related to PGT attitudes. HDGC had moderate effects on participants' quality of life, including social relationships, health behaviors, and emotional experiences including worry about cancer risk and guilt regarding familial implications. CONCLUSION: PGT was identified by participants as acceptable for use in a variety of contexts and benefits of reproductive counseling involving PGT may extend beyond CDH1 carriers to family members' reproductive behaviors. Dispositions towards PGT are governed by personal philosophy or belief systems. These findings can help guide providers counseling individuals with CDH1 variants.

Disparities in cancer genetics care by race/ethnicity among pan-cancer patients with pathogenic germline variants.

BACKGROUND: Germline risk assessment is increasing as part of cancer care; however, disparities in subsequent genetic counseling are unknown. METHODS: Pan-cancer patients were prospectively consented to tumor-normal sequencing via custom next generation sequencing panel (Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets) inclusive of germline analysis of ≥76 genes from January 2015 through December 2019 (97.5% research nonbillable) with protocol for genetics referral. Rates of pathogenic/likely pathogenic germline variants (PVs) and downstream counseling were compared across ancestry groups (mutually exclusive groups based on self-reported race/ethnicity and Ashkenazi Jewish [AJ] heritage) using nonparametric tests and multivariable logistic regression models. RESULTS: Among 15,775 patients (59.6%, non-Hispanic [NH]-White; 15.7%, AJ; 20.5%, non-White [6.9%, Asian; 6.8%, Black/African American (AA); 6.7%, Hispanic; 0.1%, Other], and 4.2%, unknown), 2663 (17%) had a PV. Non-White patients had a lower PV rate (n = 433, 13.4%) compared to NH-Whites (n = 1451, 15.4%) and AJ patients (n = 683, 27.6%), p < .01, with differences in mostly moderate and low/recessive/uncertain penetrance variants. Among 2239 patients with new PV, 1652 (73.8%) completed recommended genetic counseling. Non-White patients had lower rates of genetic counseling (67.7%) than NH-White (73.7%) and AJ patients (78.8%), p < .01, with lower rates occurring in Black/AA (63%) compared to NH-White patients, even after adjustment for confounders (odds ratio, 0.60; 95% confidence interval, 0.37-0.97; p = .036). Non-White, particularly Black/AA and Asian, probands had a trend toward lower rates and numbers of at-risk family members being seen for counseling/genetic testing. CONCLUSIONS: Despite minimizing barriers to genetic testing, non-White patients were less likely to receive recommended cancer genetics follow-up, with potential implications for oncologic care, cancer risk reduction, and at-risk family members. LAY SUMMARY: Genetic testing is becoming an important part of cancer care, and we wanted to see if genetics care was different between individuals of different backgrounds. We studied 15,775 diverse patients with cancer who had genetic testing using a test called MSK-IMPACT that was covered by research funding. Clinically important genetic findings were high in all groups. However, Black patients were less likely to get recommended counseling compared to White patients. Even after removing many roadblocks, non-White and especially Black patients were less likely to get recommended genetics care, which may affect their cancer treatments and families.

Factors Influencing Patient Preferences for Telehealth Cancer Genetic Counseling During the COVID-19 Pandemic.

PURPOSE: With onset of the COVID-19 pandemic, telehealth became the primary modality for health care appointments. This study examined patient experiences with and preferences for telehealth at a cancer genetic counseling clinic throughout the first 6 months of the pandemic (March-August 2020). METHODS: An anonymous survey assessed patient demographics; usage and prior experience with technology; emotional responses, technical experiences, and satisfaction with the telehealth appointment (via the Genetic Counseling Satisfaction Scale and Visit-Specific Satisfaction Questionnaire); preference for future telehealth; and recommendation of telehealth to others. RESULTS: Among 380 respondents, most were highly satisfied with the telehealth appointment (with 65.6% and 66.4% of participants completing the Genetic Counseling Satisfaction Scale and Visit-Specific Satisfaction Questionnaire, respectively). Multivariable analyses indicated several notable findings. Adjusting for relevant covariates, participants with less education felt significantly more concerned about telehealth than those with highest educational attainment. Participants age 40-69 years were generally more comfortable, relieved, and grateful that their appointment was scheduled as telehealth than were those older than 70 years. Women were marginally more relieved and grateful for telehealth appointments than men. As the pandemic progressed, significantly more participants were highly satisfied with their telehealth appointment and participants trended toward having greater preferences for future telehealth use. Most participants (78.6%) would recommend telehealth to others, although 50.8% preferred future in-person appointments. CONCLUSION: As the pandemic progressed, patients expressed increasing preferences for and satisfaction with telehealth. Service delivery models that incorporate individual patient preferences should be developed with special consideration to factors such as age, sex, and education level.

Pancreas cancer and BRCA: A critical subset of patients with improving therapeutic outcomes.

BACKGROUND: Patients with germline/somatic BRCA1/BRCA2 mutations (g/sBRCA1/2) comprise a distinct biologic subgroup of pancreas ductal adenocarcinoma (PDAC). METHODS: Institutional databases were queried to identify patients who had PDAC with g/sBRCA1/2. Demographics, clinicopathologic details, genomic data (annotation sBRCA1/2 according to a precision oncology knowledge base for somatic mutations), zygosity, and outcomes were abstracted. Overall survival (OS) was estimated using the Kaplan-Meier method. RESULTS: In total, 136 patients with g/sBRCA1/2 were identified between January 2011 and June 2020. Germline BRCA1/2 (gBRCA1/2) mutation was identified in 116 patients (85%). Oncogenic somatic BRCA1/2 (sBRCA1/2) mutation was present in 20 patients (15%). Seventy-seven patients had biallelic BRCA1/2 mutations (83%), and 16 (17%) had heterozygous mutations. Sixty-five patients with stage IV disease received frontline platinum therapy, and 52 (80%) had a partial response. The median OS for entire cohort was 27.6 months (95% CI, 24.9-34.5 months), and the median OS for patients who had stage IV disease was 23 months (95% CI, 19-26 months). Seventy-one patients received a poly(adenosine diphosphate ribose) polymerase (PARP) inhibitor (PARPi), and 52 received PARPi monotherapy. For maintenance PARPi, 10 patients (36%) had a partial response, 12 (43%) had stable disease, and 6 (21%) had progression of disease as their best response. Six patients (21%) received maintenance PARPi for >2 years. For those with stage IV disease who received frontline platinum, the median OS was 26 months (95% CI, 20-52 months) for biallelic patients (n = 39) and 8.66 months (95% CI, 6.2 months to not reached) for heterozygous patients (n = 4). The median OS for those who received PARPi therapy was 26.5 months (95% CI, 24-53 months) for biallelic patients (n = 25) and 8.66 months (95% CI, 7.23 months to not reached) for heterozygous patients (n = 2). CONCLUSIONS: g/sBRCA1/2 mutations did not appear to have different actionable utility. Platinum and PARPi therapies offer therapeutic benefit, and very durable outcomes are observed in a subset of patients who have g/sBRCA1/2 mutations with biallelic status.

Prevalence and Characterization of Biallelic and Monoallelic NTHL1 and MSH3 Variant Carriers From a Pan-Cancer Patient Population.

NTHL1 and MSH3 have been implicated as autosomal recessive cancer predisposition genes. Although individuals with biallelic NTHL1 and MSH3 pathogenic variants (PVs) have increased cancer and polyposis risk, risks for monoallelic carriers are uncertain. We sought to assess the prevalence and characterize NTHL1 and MSH3 from a large pan-cancer patient population. MATERIALS AND METHODS: Patients with pan-cancer (n = 11,081) underwent matched tumor-normal sequencing with consent for germline analysis. Medical records and tumors were reviewed and analyzed. Prevalence of PVs was compared with reference controls (Genome Aggregation Database). RESULTS: NTHL1-PVs were identified in 40 patients including 39 monoallelic carriers (39/11,081 = 0.35%) and one with biallelic variants (1/11,081 = 0.009%) and a diagnosis of isolated early-onset breast cancer. NTHL1-associated mutational signature 30 was identified in the tumors of the biallelic patient and two carriers. Colonic polyposis was not identified in any NTHL1 patient. MSH3-PVs were identified in 13 patients, including 12 monoallelic carriers (12/11,081 = 0.11%) and one with biallelic MSH3 variants (1/11,081 = 0.009%) and diagnoses of later-onset cancers, attenuated polyposis, and abnormal MSH3-protein expression. Of the 12 MSH3 carriers, two had early-onset cancer diagnoses with tumor loss of heterozygosity of the wild-type MSH3 allele. Ancestry-specific burden tests demonstrated that NTHL1 and MSH3 prevalence was not significantly different in this pan-cancer population versus controls. CONCLUSION: NTHL1 and MSH3 germline alterations were not enriched in this pan-cancer patient population. However, tumor-specific findings, such as mutational signature 30 and loss of heterozygosity of the wild-type allele, suggest the potential contribution of monoallelic variants to tumorigenesis in a subset of patients.

Prospective pan-cancer germline testing using MSK-IMPACT informs clinical translation in 751 patients with pediatric solid tumors.

The spectrum of germline predisposition in pediatric cancer continues to be realized. Here we report 751 solid tumor patients who underwent prospective matched tumor-normal DNA sequencing and downstream clinical use (clinicaltrials.gov NCT01775072). Germline pathogenic and likely pathogenic (P/LP) variants were reported. One or more P/LP variants were found in 18% (138/751) of individuals when including variants in low, moderate, and high penetrance dominant or recessive genes, or 13% (99/751) in moderate and high penetrance dominant genes. 34% of high or moderate penetrance variants were unexpected based on the patient's diagnosis and previous history. 76% of patients with positive results completed a clinical genetics visit, and 21% had at least one relative undergo cascade testing as a result of this testing. Clinical actionability additionally included screening, risk reduction in relatives, reproductive use, and use of targeted therapies. Germline testing should be considered for all children with cancer.

Uptake and acceptability of a mainstreaming model of hereditary cancer multigene panel testing among patients with ovarian, pancreatic, and prostate cancer.

PURPOSE: To address demands for timely germline information to guide treatments, we evaluated experiences of patients with ovarian, pancreatic, and prostate cancer with a mainstreaming genetic testing model wherein multigene panel testing was ordered by oncologists with standardized pretest patient education, and genetic counselors delivered results and post-test genetic counseling via telephone. METHODS: Among 1,203 eligible patients, we conducted a prospective single-arm study to examine patient uptake and acceptability (via self-report surveys at baseline and three weeks and three months following result return) of this mainstreaming model. RESULTS: Only 10% of eligible patients declined participation. Among 1,054 tested participants, 10% had pathogenic variants (PV), 16% had variants of uncertain significance (VUS), and 74% had no variant identified (NV). Participants reported high initial acceptability, including high satisfaction with their testing decision. Variability over time in several outcomes existed for participants with PV or NV: those with NV experienced a temporary increase in depression (pTime < 0.001; pTime2 < 0.001), and those with PV experienced a small increase in genetic testing distress (p = 0.03). Findings suggested that result type, sex, and cancer type were also associated with outcomes including clinical depression and uncertainty. CONCLUSION: This mainstreaming model may offer a feasible approach for extending access to germline genetic information.

Resolving pathogenicity classification for the CDH1 c.[715G>A] (p.Gly239Arg) Variant.

Hereditary Diffuse Gastric Cancer (HDGC) syndrome is associated with CDH1 germline likely pathogenic/pathogenic variants. Carriers of CDH1 germline likely pathogenic/pathogenic variants are predisposed to diffuse gastric cancer and lobular breast cancer. This study aims to classify the CDH1 c.[715G>A] missense variant identified in a diffuse gastric cancer prone family by performing splicing studies. RT-PCR and subsequent cloning experiments were performed to investigate whether this variant completely disrupts normal splicing. This variant preferentially abolishes normal splicing through activation of a cryptic 3' acceptor splice site within exon 6 of CDH1, presumably leading to a premature protein truncation within first extracellular domain repeat of E-cadherin protein. Our results contributed to evidence necessary to resolve pathogenicity classification of this variant, indicating that this variant is to be classified as pathogenic.

Indications for Total Gastrectomy in CDH1 Mutation Carriers and Outcomes of Risk-Reducing Minimally Invasive and Open Gastrectomies.

Importance: CDH1 variants are increasingly identified on commercially available multigene panel tests, calling for data to inform counseling of individuals without a family history of gastric cancer. Objectives: To assess association between CDH1 variant pathogenicity or family history of gastric or lobular breast cancer and identification of signet ring cell cancer and to describe outcomes of risk-reducing minimally invasive and open total gastrectomy. Design, Setting, and Participants: This cohort study was performed from January 1, 2006, to January 1, 2020, in 181 patients with CDH1 germline variants from a single institution. Interventions: Genetic counseling, esophagogastroduodenoscopy, and possible total gastrectomy. Main Outcomes and Measures: CDH1 variant classification, family cancer history, findings of signet ring cell carcinoma at esophagogastroduodenoscopy and surgery, postoperative events and weight changes, and follow-up. Results: Of 181 individuals with CDH1 germline variants (mean [SD] age at time of testing, 44 [15] years; 126 [70%] female), 165 harbored a pathogenic or likely pathogenic variant. Of these patients, 101 underwent open (n = 58) or minimally invasive (n = 43) total gastrectomy. Anastomotic leaks that required drainage were infrequent (n = 3), and median long-term weight loss was 20% (interquartile range [IQR], 10%-23%). In those undergoing minimally invasive operations, more lymph nodes were retrieved (median, 28 [IQR, 20-34] vs 15 [IQR, 9-19]; P < .001) and the hospital stay was 1 day shorter (median, 6 [IQR, 5-7] vs 7 [IQR, 6-7] days; P = .04). Signet ring cell cancer was identified in the surgical specimens of 85 of 95 patients (89%) with a family history of gastric cancer and 4 of 6 patients (67%) who lacked a family history. Among the latter 6 patients, 4 had a personal or family history of lobular breast cancer, including 2 with signet ring cell cancer. Of the 16 patients with pathogenic or likely pathogenic CDH1 variants who presented with locally advanced or metastatic gastric cancer, 3 (19%) had no family history of gastric cancer or personal or family history of lobular breast cancer. Conclusions and Relevance: Total gastrectomy may be warranted for patients with pathogenic or likely pathogenic CDH1 variants and a family history of gastric or lobular breast cancer and may be appropriate for those without a family history. A minimally invasive approach is feasible and may be preferred for selected patients.

An Emerging Paradigm for Germline Testing in Pancreatic Ductal Adenocarcinoma and Immediate Implications for Clinical Practice: A Review.

Importance: Pancreatic ductal adenocarcinoma (PDAC) is a malignant neoplasm with a rising incidence and is a leading public health challenge. Pancreatic ductal adenocarcinoma has been well characterized genomically, with findings of therapeutic actionability that have substantive implications for clinical practice based on recent high-level evidence. Observations: Pathogenic germline alterations (PGAs) are relatively common in individuals with PDAC, as evidenced in multiple recent data sets, with a frequency of approximately 10%. The most common PGAs are in BRCA1, BRCA2, and ATM and more rarely in PALB2, MLH1, MSH2, MSH6, PMS2, CDKN2A, and TP53, among others, with an aggregate frequency of 3.8% to 9.7%. These PGAs are of key interest owing to therapeutic actionability and the downstream identification of at-risk family members and possible hereditary cancer syndromes. Approximately 3% to 7% of individuals with PDAC harbor a BRCA1 or BRCA2 mutation, which are among the most frequently mutated genes in PDAC. Recent updates to the American Society of Clinical Oncology and the National Comprehensive Cancer Network guidelines recommend risk assessment for all individuals with PDAC irrespective of personal or family history or ethnicity. Treatment implications include the use of checkpoint inhibitor therapy for mismatch repair-deficient PDAC and the validation of poly-ADP (adenosine diphosphate)-ribose polymerase inhibitor (PARPi) therapy as a maintenance strategy in platinum-sensitive PDAC. Conclusions and Relevance: With increasing evidence and slow improvement of outcomes, PDAC has entered the era of precision medicine. Germline mutations have been identified in key genes with an aggregate frequency of 3.8% to 9.7%, several of which are therapeutically actionable with platinum, PARPi, and checkpoint inhibitor therapy. Potential therapeutic targets need to be actively sought and identified.

Risk of Metachronous Colorectal Neoplasm after a Segmental Colectomy in Lynch Syndrome Patients According to Mismatch Repair Gene Status.

BACKGROUND: Because of increased risk of metachronous colorectal cancer (CRC), all patients with Lynch syndrome (LS) are offered a total colectomy. However, because metachronous CRC rate by mismatch repair (MMR) gene is uncertain, and total colectomy negatively impacts quality of life, it remains unclear whether segmental resection is indicated for lower penetrance MMR genes. We evaluated metachronous CRC incidence according to MMR gene in LS patients who underwent a segmental colectomy. STUDY DESIGN: Single-center, retrospective cohort study in patients with an earlier colectomy for CRC and an MMR germline mutation in MLH1, MSH2, MSH6, or PMS2 followed prospectively in a hereditary CRC family registry. All patients underwent surveillance colonoscopy. Metachronous CRC was defined as one detected more than 1 year after index resection. Primary end point was cumulative incidence of metachronous CRC overall and by MMR gene. RESULTS: One hundred and ten patients were included: 35 with MLH1 likely pathogenic/pathogenic (LP/P) variants (32%), 42 MSH2 (38%), 20 MSH6 (18%), and 13 PMS2 (12%). Median follow-up 4.26 years (range 0.53 to 19.92 years). Overall, metachronous CRC developed in 22 patients (20%). At 10-year follow-up, incidence was 12% (95% CI 6% to 23%), with no metachronous CRC detected in patients with a PMS2 or MSH6 LP/P variant. CONCLUSIONS: After index segmental resection, metachronous CRC is less likely to develop in LS patients with MSH6 or PMS2 LP/P variant than in MLH1 or MSH2 carriers. Our data support segmental resection and long-term colonoscopic surveillance rather than total colectomy in carefully selected, well-informed LS patients with MSH6 or PMS2 LP/P variant.

Patients' Medical and Psychosocial Experiences After Detection of a CDH1 Variant With Multigene Panel Testing.

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.

Phase 1 trial evaluating cisplatin, gemcitabine, and veliparib in 2 patient cohorts: Germline BRCA mutation carriers and wild-type BRCA pancreatic ductal adenocarcinoma.

BACKGROUND: A phase 1 trial was used to evaluate a combination of cisplatin, gemcitabine, and escalating doses of veliparib in patients with untreated advanced pancreatic ductal adenocarcinoma (PDAC) in 2 cohorts: a germline BRCA1/2-mutated (BRCA+) cohort and a wild-type BRCA (BRCA-) cohort. The aims were to determine the safety, dose-limiting toxicities (DLTs), maximum tolerated dose, and recommended phase 2 dose (RP2D) of veliparib combined with cisplatin and gemcitabine and to assess the antitumor efficacy (Response Evaluation Criteria in Solid Tumors, version 1.1) and overall survival. METHODS: Gemcitabine and cisplatin were dosed at 600 and 25 mg/m2 , respectively, over 30 minutes on days 3 and 10 of a 21-day cycle. Four dose levels of veliparib were evaluated: 20 (dose level 0), 40 (dose level 1), and 80 mg (dose level 2) given orally twice daily on days 1 to 12 and 80 mg given twice daily on days 1 to 21 (dose level 2A [DL2A]). RESULTS: Seventeen patients were enrolled: 9 BRCA+ patients, 7 BRCA- patients, and 1 patient with an unknown status. DLTs were reached at DL2A (80 mg twice daily on days 1 to 21). Two of the 5 patients in this cohort (40%) experienced grade 4 neutropenia and thrombocytopenia. Two grade 5 events occurred on protocol. The objective response rate in the BRCA+ cohort was 7 of 9 (77.8%). The median overall survival for BRCA+ patients was 23.3 months (95% confidence interval [CI], 3.8-30.2 months). The median overall survival for BRCA- patients was 11 months (95% CI, 1.5-12.1 months). CONCLUSIONS: The RP2D of veliparib was 80 mg by mouth twice daily on days 1 to 12 in combination with cisplatin and gemcitabine; the DLT was myelosuppression. Substantial antitumor activity was seen in BRCA+ PDAC. A randomized phase 2 trial is currently evaluating cisplatin and gemcitabine with and without veliparib for BRCA+ PDAC (NCT01585805). Cancer 2018;124:1374-82. © 2018 American Cancer Society.

Phase II trial of veliparib in patients with previously treated BRCA-mutated pancreas ductal adenocarcinoma.

PURPOSE: BRCA-associated cancers have increased sensitivity to poly(ADP-ribose) polymerase inhibitors (PARPis). This single arm, non-randomised, multicentre phase II trial evaluated the response rate of veliparib in patients with previously treated BRCA1/2- or PALB2-mutant pancreatic adenocarcinoma (PDAC). METHODS: Patients with stage III/IV PDAC and known germline BRCA1/2 or PALB2 mutation, 1-2 lines of treatment, Eastern Cooperative Oncology Group 0-2, were enrolled. Veliparib was dosed at a volume of 300 mg twice-daily (N = 3), then 400 mg twice-daily (N = 15) days 1-28. The primary end-point was to determine the response rate of veliparib; secondary end-points included progression-free survival (PFS), duration of response, overall survival (OS) and safety. RESULTS: Sixteen patients were enrolled; male N = 8 (50%). Median age was 52 years (range 43-77). Five (31%) had a BRCA1 and 11 (69%) had a BRCA2 mutation. Fourteen (88%) patients had received prior platinum-based therapy. No confirmed partial responses (PRs) were seen: one (6%) unconfirmed PR was observed at 4 months with disease progression (PD) at 6 months; four (25%) had stable disease (SD), whereas 11 (69%) had PD as best response including one with clinical PD. Median PFS was 1.7 months (95% confidence interval [CI] 1.57-1.83) and median OS was 3.1 months (95% CI 1.9-4.1). Six (38%) patients had grade III toxicity, including fatigue (N = 3), haematology (N = 2) and nausea (N = 1). CONCLUSIONS: Veliparib was well tolerated, but no confirmed response was observed although four (25%) patients remained on study with SD for ≥ 4 months. Additional strategies in this population are needed, and ongoing trials are evaluating PARPis combined with chemotherapy (NCT01585805) and as a maintenance strategy (NCT02184195).

Contiguous gene deletion of chromosome 2p16.3-p21 as a cause of Lynch syndrome.

Lynch syndrome is an autosomal dominant condition caused by pathogenic mutations in the DNA mismatch repair (MMR) genes. Although commonly associated with clinical features such as intellectual disability and congenital anomalies, contiguous gene deletions may also result in cancer predisposition syndromes. We report on a 52-year-old male with Lynch syndrome caused by deletion of chromosome 2p16.3-p21. The patient had intellectual disability and presented with a prostatic adenocarcinoma with an incidentally identified synchronous sigmoid adenocarcinoma that exhibited deficient MMR with an absence of MSH2 and MSH6 protein expression. Family history was unrevealing. Physical exam revealed short stature, brachycephaly with a narrow forehead and short philtrum, brachydactyly of the hands, palmar transverse crease, broad and small feet with hyperpigmentation of the soles. The patient underwent total colectomy with ileorectal anastomosis for a pT3N1 sigmoid adenocarcinoma. Germline genetic testing of the MSH2, MSH6, and EPCAM genes revealed full gene deletions. SNP-array based DNA copy number analysis identified a deletion of 4.8 Mb at 2p16.3-p21. In addition to the three Lynch syndrome associated genes, the deleted chromosomal section encompassed genes including NRXN1, CRIPT, CALM2, FBXO11, LHCGR, MCFD2, TTC7A, EPAS1, PRKCE, and 15 others. Contiguous gene deletions have been described in other inherited cancer predisposition syndromes, such as Familial Adenomatous Polyposis. Our report and review of the literature suggests that contiguous gene deletion within the 2p16-p21 chromosomal region is a rare cause of Lynch syndrome, but presents with distinct phenotypic features, highlighting the need for recognition and awareness of this syndromic entity.

Psychosocial factors associated with the uptake of contralateral prophylactic mastectomy among BRCA1/2 mutation noncarriers with newly diagnosed breast cancer.

PURPOSE: Women who are newly diagnosed with breast cancer may consider contralateral prophylactic mastectomy (CPM) to reduce their future risk of cancer in their unaffected breast. Pre-surgical BRCA1/2 genetic testing can provide valuable risk information to guide this choice. However, little is understood about why BRCA1/2 mutation noncarriers, who are generally not at substantially elevated risk of contralateral disease, select CPM. METHODS: We examined the uptake of CPM among breast cancer patients identified as BRCA1/2 mutation noncarriers (n = 92) as part of a larger prospective study of the impact of pre-surgical BRCA1/2 testing. Data obtained from self-report questionnaires and patient medical records were used to examine associations between theoretically relevant background and psychosocial factors and BRCA1/2 mutation noncarriers' decisions to undergo CPM. RESULTS: Among BRCA1/2 mutation noncarriers, 25% (n = 23) elected to undergo CPM. Psychosocial factors including a self-reported physician recommendation for CPM, greater perceived contralateral breast cancer risk, and greater perceived benefits of CPM were all significantly associated with the uptake of CPM. CONCLUSIONS: A sizeable minority of BRCA1/2 mutation noncarriers choose to undergo CPM after learning their mutation status through pre-surgical genetic testing. BRCA1/2 mutation noncarriers' cognitive perceptions and social influences appear to be important in shaping their decisions regarding CPM. This work highlights the importance of several psychosocial factors in influencing patients' surgical decisions. Future research is needed that examines the formation of BRCA1/2 mutation noncarriers' beliefs regarding their disease and available treatment options, and that characterizes the physician-patient communication that occurs in this complex decision-making context.

Reliable Detection of Mismatch Repair Deficiency in Colorectal Cancers Using Mutational Load in Next-Generation Sequencing Panels.

PURPOSE: Tumor screening for Lynch syndrome is recommended in all or most patients with colorectal cancer (CRC). In metastatic CRC, sequencing of RAS/BRAF is necessary to guide clinical management. We hypothesized that a next-generation sequencing (NGS) panel that identifies RAS/BRAF and other actionable mutations could also reliably identify tumors with DNA mismatch repair protein deficiency (MMR-D) on the basis of increased mutational load. METHODS: We identified all CRCs that underwent genomic mutation profiling with a custom NGS assay (MSK-IMPACT) between March 2014 and July 2015. Tumor mutational load, with exclusion of copy number changes, was determined for each case and compared with MMR status as determined by routine immunohistochemistry. RESULTS: Tumors from 224 patients with unique CRC analyzed for MMR status also underwent MSK-IMPACT. Thirteen percent (n = 28) exhibited MMR-D by immunohistochemistry. Using the 341-gene assay, 100% of the 193 tumors with < 20 mutations were MMR-proficient. Of 31 tumors with ≥ 20 mutations, 28 (90%) were MMR-D. The three remaining tumors were easily identified as being distinct from the MMR-D tumors with > 150 mutations each. Each of these tumors harbored the P286R hotspot POLE mutation consistent with the ultramutator phenotype. Among MMR-D tumors, the median number of mutations was 50 (range, 20 to 90) compared with six (range, 0 to 17) in MMR-proficient/POLE wild-type tumors (P < .001). With a mutational load cutoff of ≥ 20 and < 150 for MMR-D detection, sensitivity and specificity were both 1.0 (95% CI, 0.93 to 1.0). CONCLUSION: A cutoff for mutational load can be identified via multigene NGS tumor profiling, which provides a highly accurate means of screening for MMR-D in the same assay that is used for tumor genotyping.

Identification of germline genetic mutations in patients with pancreatic cancer.

BACKGROUND: Pancreatic adenocarcinoma (PAC) is part of several cancer predisposition syndromes; however, indications for genetic counseling/testing are not well-defined. In the current study, the authors sought to determine mutation prevalence and characteristics that are predictive of an inherited predisposition for PAC. METHODS: A total of 175 consecutive patients with PAC who underwent clinical genetics assessment at Memorial Sloan Kettering Cancer Center between 2011 and 2014 were identified. Clinical data, family history, and germline results were evaluated. RESULTS: Among 159 patients with PAC who pursued genetic testing, 24 pathogenic mutations were identified (15.1%; 95% confidence interval, 9.5%-20.7%), including BRCA2 (13 mutations), BRCA1 (4 mutations), p16 (2 mutations), PALB2 (1 mutation), and Lynch syndrome (4 mutations). BRCA1/BRCA2 prevalence was 13.7% in Ashkenazi Jewish (AJ) patients (95 patients) and 7.1% in non-AJ patients (56 patients). In AJ patients with a strong, weak, or absent family history of BRCA-associated cancers, the mutation prevalence was 16.7%, 15.8%, and 7.4%, respectively. The mean age at the time of diagnosis in all mutation carriers was 58.5 years (range, 45-75 years) compared with 64 years (range, 27-87 years) in those not carrying a mutation (P = .02). Although BRCA2 was the most common mutation identified, no patients with early-onset PAC (diagnosed at age ≤ 50 years) harbored a BRCA2 mutation and the mean age at diagnosis in BRCA2 carriers was equivalent to that of individuals who were not mutation carriers (P = .34). Mutation prevalence in patients with early-onset disease (21 patients) was 28.6%, including BRCA1 (2 mutations), p16 (2 mutations), MSH2 (1 mutation), and MLH1 (1 mutation). CONCLUSIONS: Mutations in BRCA2 account for > 50% of patients with PAC with an identified susceptibility syndrome. AJ patients were found to have high BRCA1/BRCA2 prevalence regardless of personal/family history, suggesting that ancestry alone indicates a need for genetic evaluation. With the exception of BRCA2-associated PAC, an inherited predisposition for PAC is associated with an earlier age at PAC diagnosis, suggesting that this subset of patients may also represent a population warranting further evaluation.