Abstract only
10603
Background: Clinicians have used strict criteria to determine eligibility for cancer susceptibility (CS) testing and have limited genetic assessment to cancer-related genes. ...However, half of all CS mutation carriers are missed by criteria-based testing and there may be an unrecognized opportunity to modify care for patients who have rare but actionable genetic disorders as defined by the American College of Medical Genetics (ACMG). With the aim of improving patient outcomes through precision genomics, we initiated an enterprise-wide program to offer somatic and germline sequencing to all patients. Methods: We offer consented patients clinical grade paired somatic & germline WES/ RNA seq and panel germline testing for cancer (156 genes) and ACMG disorders (59 genes). Results are reviewed by a Precision Oncology Tumor Board. Somatic results are returned by the treating team. Germline results are returned by phone (genetic counselor, GC) followed by a clinic visit (GC+MD) for those with pathogenic/likely pathogenic (P/LP) mutations and selected variants of uncertain significant. We evaluated the proportions of patients with somatic findings suggestive of germline conditions and those carrying P/LP mutations in CS and ACMG genes. Results: 1,804 patients enrolled and received somatic sequencing: 52% female; 51% non-Hispanic White/ 20% Hispanic White/ 18% Asian/ 4% Black/ 7% other; median age 64. Review of somatic data suggest that 14% have findings suggestive of germline conditions based on factors such as TMB, MSI, and young age. Of the patients offered germline testing, >95% opted to receive CS/ACMG results. To date, we have sequenced 684 patients for CS and 647 for ACMG. 18% of patients had P/LP mutations in CS genes and 4% had P/LP mutations in ACMG non-cancer genes (Table). Conclusions: Prospective somatic/germline sequencing of unselected cancer patients reveals tumor findings suggestive of germline disorders and identifies patients with CS and non-cancer genetic conditions. These findings highlight the promise of a comprehensive sequencing approach to help guide cancer treatment, management of unrecognized cancer risk and the need for concomitant management of rare disorders such as arrhythmogenic cardiomyopathy and susceptibility to adverse reactions with anesthesia.Table: see text
Abstract
Background: To enable genomic care for all City of Hope (COH) patients, we implemented an enterprise-wide Precision Medicine program including 7 of our clinical network sites. Consented ...patients with and without cancer are eligible to opt into germline testing (155 gene cancer predisposition panel and ACMG 59 Actionable Disorders panel) and paired tumor-normal whole exome/RNA transcriptome sequencing. All assays are CAP-CLIA approved. Results are added to the electronic medical record (EMR). We describe the process of implementation through return of results (RoR). Methods: Potentially eligible patients are identified by their provider or through the EMR. Clinical Research Assistants (n=8, main campus) and Advance Practice Providers (APPs) (n=14 Genetic Counselors or n=1 Genetics Nurse Practitioner) and Licensed Vocational Nurses (n=5, clinical network) consent patients in-person and remotely. Clinical Research Nurses (n=5) or APPs order testing through the EMR, with treating providers copied on somatic results and GCs copied on germline results. All results are systematically reviewed by GCs and/or the weekly COH Precision Oncology Tumor Board (POTB). Results: From July 9, 2020 through August 26, 2022 12,105 patients have been offered participation, with 10,376 (85.7%) enrolling (7,892 original consents/ 2,484 reconsents), 735 (6.1%) declining, 984 (8.1%) deferring, and 10 (.1% ) with other consent statuses. 98.9% (10,259/10,376) opted for cancer predisposition germline testing and 98.5% (10,225/10,376) opted for ACMG Actionable Disorders testing 91.5% (9,497/10,376) patients agreed to future contact about additional research studies. 6,512 somatic tests have been reviewed (representing 6,295 patients) and presented through POTB. Somatic genomic results are uploaded to the EMR via PDF and returned by the treating physician. Germline results are returned through the EPIC genomics module. To scale RoR, patients with negative results, variants of unknown significance, and carriers for recessive conditions are sent letters. Patients with a cancer predisposition P/LP variant are disclosed via phone by a GC and referred to COH Cancer Genomics for counseling whereas patients with P/LP non-cancer ACMG variants are referred for outside genetic counseling through the testing laboratory. To improve efficiency, we do not notify patients of non-actionable variant reclassifications. Conclusion: We outline a new care model for the delivery of germline and somatic genetic testing at scale. High consent and opt-in rates for germline testing demonstrate patient interest and feasibility. Future work is planned to assess the impact of testing on clinical care and outcomes.
Citation Format: Ilana Solomon, Heather Hampel, Kevin McDonnell, Kathleen Blazer, Alex Capasso, Anuja Chitre, Sandra Dreike, Hunaydah Elfarawi, Lauren Gima, Christine Hong, Gregory Idos, Elisabeth King, Rachelle Manookian, Bita Nehoray, Wai Park, Michael Restrepo, Susan Shehayeb, Elise Sobotka, Duveen Sturgeon, Elyssa Zukin, Stacy W. Gray, Stephen B. Gruber. The INSPIRE Study (Implementing Next-generation Sequencing for Precision Intervention and Risk Evaluation): scaling return of genomic results. abstract. In: Proceedings of the AACR Special Conference: Precision Prevention, Early Detection, and Interception of Cancer; 2022 Nov 17-19; Austin, TX. Philadelphia (PA): AACR; Can Prev Res 2023;16(1 Suppl): Abstract nr P051.
Background & Aims African Americans (AAs) have the highest incidence of and mortality resulting from colorectal cancer (CRC) in the United States. Few data are available on genetic and nongenetic ...risk factors for CRC among AAs. Little is known about cancer risks and mutations in mismatch repair (MMR) genes in AAs with the most common inherited CRC condition, Lynch syndrome. We aimed to characterize phenotype, mutation spectrum, and risk of CRC in AAs with Lynch syndrome. Methods We performed a retrospective study of AAs with mutations in MMR genes ( MLH1 , MSH2 , MSH6 , and PMS2 ) using databases from 13 US referral centers. We analyzed data on personal and family histories of cancer. Modified segregation analysis conditioned on ascertainment criteria was used to estimate age- and sex-specific CRC cumulative risk, studying members of the mutation-carrying families. Results We identified 51 AA families with deleterious mutations that disrupt function of the MMR gene product: 31 in MLH1 (61%), 11 in MSH2 (21%), 3 in MSH6 (6%), and 6 in PMS2 (12%); 8 mutations were detected in more than 1 individual, and 11 have not been previously reported. In the 920 members of the 51 families with deleterious mutations, the cumulative risks of CRC at 80 years of age were estimated to be 36.2% (95% confidence interval CI, 10.5%–83.9%) for men and 29.7% (95% CI, 8.31%–76.1%) for women. CRC risk was significantly higher among individuals with mutations in MLH1 or MSH2 (hazard ratio, 13.9; 95% CI, 3.44–56.5). Conclusions We estimate the cumulative risk for CRC in AAs with MMR gene mutations to be similar to that of individuals of European descent with Lynch syndrome. Two-thirds of mutations were found in MLH1, some of which were found in multiple individuals and some that have not been previously reported. Differences in mutation spectrum are likely to reflect the genetic diversity of this population.
Abstract
Table 1. Incidence of BRCA 1 and 2 mutations by Race and Ethnicity BRCA1 BRCA2 BRCA1 or 2 VUS/Negative Native American 0 1 1 6 Asian 2 3 5 150 Black/African American 3 2 5 48 Native Hawaiian ...or Pacific Islander 0 0 0 5 Other 1 1 1* 26 White 25 17 42 688 Unknown 0 0 0 20 Declined 1 0 1 24 TOTAL 32 24 55 967 * Patient had both BRCA1 and BRCA2 mutations
Citation Format: Joanne Mortimer, Sidney S. Lindsey, Ilana Solomon, Wai Park, Duveen Sturgeon, Kathleen Blazer, Stacy Gray, Joseph Bonner, Xiaoyu Xia, Stephen Gruber. Prevalence of BRCA1/2 mutations in an underrepresented population of women with breast cancer: Observations from the City of Hope INSPIRE study abstract. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-05-03.
Approximately 5–10% of all pancreatic cancer patients carry a predisposing mutation in a known susceptibility gene. Since >90% of patients present with late stage disease, it is crucial to identify ...high risk individuals who may be amenable to early detection or other prevention. To explore the spectrum of hereditary pancreatic cancer susceptibility, we evaluated germline DNA from pancreatic cancer participants (n = 53) from a large hereditary cancer registry. For those without a known predisposition mutation gene (n = 49), germline next generation sequencing was completed using targeted capture for 706 candidate genes. We identified 16 of 53 participants (30%) with a pathogenic (P) or likely pathogenic (LP) variant that may be related to their hereditary pancreatic cancer predisposition; seven had mutations in genes associated with well-known cancer syndromes (13%)
ATM
(2),
BRCA2
(3),
MSH2
(1),
MSH6
(1). Many had mutations in Fanconi anemia complex genes
BRCA2
(3 participants),
FANCF, FANCM
. Eight participants had rare protein truncating variants of uncertain significance with no other P or LP variants. Earlier age of pancreatic cancer diagnosis (57.5 vs 64.8 years) was indicative of possessing a P or LP variant, as was cancer family history (p values <0.0001). Our multigene panel approach for identifying known cancer predisposing genetic susceptibility in those at risk for hereditary pancreatic cancer may have direct applicability to clinical practice in cases with mutations in actionable genes. Future pancreatic cancer predisposition studies should include evaluation of the Fanconi anemia genes.
Advances in next-generation sequencing (NGS) technologies are driving a shift from single-gene to multigene panel testing for clinical genetic cancer risk assessment (GCRA). This study explored ...perceptions, experiences, and challenges with NGS testing for GCRA among U.S. community-based clinicians.
Surveys delivered at initial and 8-month time points, and 12-month tracking of cases presented in a multidisciplinary web-based case conference series, were conducted with GCRA providers who participated in a 235-member nationwide community of practice.
The proportion of respondents ordering panel tests rose from 29% at initial survey (27/94) to 44% (46/107) within 8 months. Respondents reported significantly less confidence about interpreting and counseling about NGS compared with single-gene test results (p < 0.0001 for all comparisons). The most cited reasons for not ordering NGS tests included concerns about clinical utility, interpreting and communicating results, and lack of knowledge/skills. Multigene panels were used in 204/668 cases presented during 2013, yielding 37 (18%) deleterious (7% in low/moderate-penetrance genes), 88 (43%) with ≥1 variant of uncertain significance, 77 (38%) uninformative negative, and 2 (1%) inconclusive results.
Despite concerns about utility and ability to interpret/counsel about NGS results, a rapidly increasing uptake of NGS testing among community clinicians was documented. Challenges identified in case discussions point to the need for ongoing education, practice-based support, and opportunities to partner in research that contributes to characterization of lesser known genes.
•Many participants were identified with mutations in clinically-actionable genes.•Age of onset and family history of gastric cancer were mutation status predictors.•Our findings support multigene ...panels in identifying gastric cancer predisposition.
Few susceptibility genes for gastric cancer have been identified. We sought to identify germline susceptibility genes from participants with gastric cancer from an international hereditary cancer research network. Adults with gastric cancer of any histology, and with a germline DNA sample (n = 51), were retrospectively selected. For those without previously identified germline mutations (n = 43), sequencing was performed for 706 candidate genes. Twenty pathogenic or likely pathogenic variants were identified among 18 participants. Eight of the 18 participants had previous positive clinical testing, including six with CDH1 pathogenic or likely pathogenic variants, and two with pathogenic MSH2 and TP53 variants. Of the remaining 10, six were in BRCA1 DNA damage response pathway genes (ATM, ATR, BRCA2, BRIP1, FANCC, TP53), other variants were identified in CTNNA1, FLCN, SBDS, and GNAS. Participants identified with pathogenic or likely pathogenic variants were younger at gastric cancer diagnosis than those without, 39.1 versus 48.0 years, and over 50% had a close family member with gastric cancer (p-values < 0.0001). In conclusion, many participants were identified with mutations in clinically-actionable genes. Age of onset and family history of gastric cancer were mutation status predictors. Our findings support multigene panels in identifying gastric cancer predisposition.
Abstract
BACKGROUND: Clinicians who provide genetic cancer risk assessment (GCRA) are dependent on laboratory reporting of germline results to inform cancer screening and treatment recommendations. ...Efforts to enhance variant classification and harmonization, such as ClinVar, will lead to an increase in the number of variants being reclassified. Given that the impact of variant reclassification on care is unknown, we evaluated the frequency and clinical impact of variant reclassification on individuals seen for GCRA.
METHODS: We retrospectively evaluated data on 7,356 participants enrolled through the Clinical Cancer Genomics Community Research Network (CCGCRN) at City of Hope and Olive View Medical Center from September 1996- October 2016.
RESULTS: 4,969 commercial genetic tests yielded a total of 1,610 variants of any category, of which 181 unique variants in 20 genes were reclassified. BRCA1 and BRCA2 (BRCA) and mismatch repair genes comprised 73.5% and 5.5% of the genes reclassified,
respectively. Reclassification impacted 225 individuals (97% women) from 217 families; 89% of these individuals (n=201) had a personal history of cancer. The interval between initial report and variant reclassification averaged 3 years (17 days- 13 years). Minorities had higher reclassification rates as compared to non-Hispanic white participants (P = 0.0149). Of the 181 unique reclassifications, 164 (90.6%) of variants were downgraded. Sixteen reclassifications led to changes in clinical care. Thirteen variants carried by 15 individuals were upgraded from a variant of uncertain significance (VUS) to likely pathogenic or pathogenic (10 BRCA, 3 MLH1 or MSH2). These reclassifications prompted additional prophylactic surgical interventions (i.e., bilateral salpingo-oophorectomy), specialist referrals, and surveillance recommendations for at risk patients and family members. Three variants (NBN p.Arg215Trp, PTEN p.Ala79Thr, and MET c.1200+2T>C) were downgraded from likely pathogenic or pathogenic to VUS. Prior to downgrade to VUS, 2 cases had unnecessary surveillance procedures.
CONCLUSIONS: Since many genomic variants will be reclassified over time, it is critical that laboratories deliver prompt notification of reclassifications, and that providers involved in GCRA discuss the possibility of variant reclassification with patients and family members and collect patient/proxy information during informed consent so that re-contact is possible. Given the non-trivial effort required for variant reclassification and patient/participant re-contact, system-level interventions are needed to facilitate genomic reinterpretation and the return of results to individuals over time.
Citation Format: Thomas P. Slavin, Stacy W. Gray, Lily R. Van Tongeren, Ilana Solomon, Christina Rybak, Bita Nehoray, Lili Kuzmich, Mariana Niell-Swiller, Kathleen R. Blazer, Kai Yang, Julie Culver, Sharon Sand, Danielle Castillo, Josef Herzog, Jeffrey N. Weitzel. Variant reclassifications in hereditary cancer genetics and their implications for clinical care abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4273. doi:10.1158/1538-7445.AM2017-4273
Abstract
Background: Fanconi Anemia (FA) proteins facilitate homologous recombination (HR)-mediated repair of DNA interstrand cross-links. Germline monoallelic, pathogenic/likely pathogenic (P/LP) ...variants in the highly-penetrant (HP) breast cancer (BC) FA genes, BRCA1 (FANCS), BRCA2 (FANCD1) and PALB2 (FANCN)), compromise HR and predispose to hereditary BC. The effects of monoallelic, pathogenic variants in other non-HP BC FA genes upon HR and BC predisposition remain less understood. In this investigation we report the germline mutational landscape of FA gene P/LP variants and somatic molecular consequences of patients with BC diagnoses from City of Hope’s (COH) INSPIRE (Implementing Next-generation Sequencing for Precision Intervention and Risk Evaluation) study.
Methods: COH-INSPIRE is a universal access study open to all patients at COH with a personal and/or family history of cancer. Patients undergo custom panel-based germline genetic testing to detect P/LP single nucleotide variants (SNVs), short insertions/deletions (indels) and exon-level deletions/duplications in 155 cancer-predisposition genes including the HP BC FA genes and 15 non-HP BC FA genes FANCA, FANCB, FANCC, FANCD2, FANCE, FANCF, FANCG, FANCI, FANCJ (BRIP1), FANCL, FANCM, FANCO (RAD51C), FANCP (SLX4), FANCQ (ERCC4) and FANCU (XRCC2). Patients’ tumor specimens undergo somatic tumor (>400X)-normal (>180X) whole exome and transcriptome sequencing (>50 million reads). Somatic sequencing identifies P/LP SNVs, indels, copy number events, and fusions. Secondary analyses assessed somatic homologous recombination deficiency (HRD) by examining tumor mutational signatures, as well as an ensemble HRD score derived by combining individual genomic loss of heterozygosity, telomeric allelic imbalance and large-scale molecular transition scores. Reference comparison of germline and somatic features to current FDA therapeutic guidelines and NIH clinical trials registrations determined eligibility for precision therapeutic intervention and clinical trial enrollment.
Results: Of 7,584 patients enrolled in COH-INSPIRE, 1,651 (21.8%) patients had a BC diagnosis. Germline panel testing of BC patients identified 204 (12.4%) with germline P/LP variant in a FA gene. Greater than one third of FA gene-altered BC patients (37.7%) carried a P/LP variant in a non-HP BC FA gene. We observed that BC patients with a non-HP BC FA gene variant may demonstrate HR compromise as evidenced by presence of a Signature 3 mutational profile or an elevated combined HRD score (> 33 and/or > 42). (Table 1) Further, we identified ostensible segregation of triple negative BC in a family harboring a germline pathogenic variant in FANCG. With regard to precision clinical actionability (i.e. qualification for targeted therapeutic intervention PARP inhibitor (PARPi) and/or clinical trial) for patients with advanced stage BC: All patients with germline P/LP HP BC FA gene variant and 20.7% (N=16) of patients with a P/LP FA non-HPBC FA gene variant met criteria for treatment with on/off-label PARPi. 100% of patients with advanced BC with germline P/LP HP BC or non-HPBC FA gene variant qualified for a clinical trial.
Conclusions: Patients with BC often carry a germline monoallelic, P/LP FA gene variant; in more than one third, the FA gene alteration occurs in a non-HP BC FA gene. BC patients harboring a monoallelic germline non-HP BC P/LP FA gene may exhibit somatic mutational signatures and HRD scoring consistent with compromise of HR. Somatic tumor evaluation of BC patients with germline P/LP non-HP BC FA gene variants expands opportunities for precision therapeutic intervention and clinical trial enrollment. Continued appraisal will clarify emerging questions of germline non-HP P/LP FA gene-associated autosomal dominant BC risk and management as well as facilitate optimization of precision BC care.
Table 1 Summary Molecular Features of BC patients with P/LP Variants in FA gene from COH-INSPIRE
Citation Format: Laura Kruper, Kevin McDonnell, Joseph Bonner, Kevin K. Tsang, Veronica Jones, Joanne Mortimer, Sidney S. Lindsey, Ilana Solomon, Heather Hampel, Wai Park, Gregory E. Idos, Stacy Gray, Stephen Gruber. PD14-03 Reappraising the Fanconi Anemia DNA repair pathway in breast cancer risk and precision intervention: Insights and opportunities from the City of Hope INSPIRE study abstract. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD14-03.