Abstract 1471P
Background
Recent research suggests a role for BRCA1/2 or ATM gene mutations in metastatic pancreatic cancer (mPC) as a predictive marker of clinical benefit from platinum-based chemotherapy and targeted therapies. However, there is little data on the prognostic impact of BRCA/ATM mutation on all-cause overall survival in mPC.
Methods
In this retrospective cohort study, we identified patients aged ≥18 years with mPC (≥2 PC diagnoses within 90 days plus ≥1 diagnosis or ≥2 note mentions of metastatic disease) in Optum’s de-identified electronic health record (EHR) database (1/1/2011 – 6/30/2020; N=42.5M total lives). Index date was the first diagnosis/note mention of metastatic disease. Patients with >1 other cancer type in the 12-month baseline were excluded. Patients were stratified by BRCA/ATM status and followed for up to 36 months to assess overall survival (OS). Death was captured from the EHR and linked social security and obituary data. Survival differences were evaluated using the Kaplan-Meier log-rank test and Cox Proportional-Hazards model, adjusting for demographics, comorbidities, clinical and prognostic factors, frailty, and number and site of metastases.
Results
Among 17,359 patients with mPC, 546 (3.1%) were tested for BRCA/ATM: 182 (33.3%) were BRCA+/ATM+ (POS), 94 (17.2%) BRCA-/ATM- (NEG) and 270 (49.5%) unknown status. POS and NEG patients were 66% and 60% female; with mean (SD) age 65.1 (11.0) and 63.3 (10.5) years, respectively. Baseline Charlson Comorbidity Score was 6.3 (2.3) and 6.2 (2.3), respectively. There were few meaningful differences in clinical and prognostic factors at baseline. Among patients with index dates prior to 7/1/2019 (to allow for at least one year of post-index data; n=216), 1-year OS rates were not significantly different between POS (60%) and NEG (64%) patients (p=0.29); unadjusted hazard ratio (HR) 1.28 (95% CI =0.80–2.05); adjusted HR 1.10 (95% CI 0.60–2.04).
Conclusions
In this study, there were no statistically significant differences in demographic, clinical and prognostic factors, or 1-year OS rates between patients with or without BRCA/ATM mutation. Additional research is needed to evaluate the association between BRCA/ATM status and overall survival.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Merck & Co., Inc.
Funding
Merck & Co., Inc.
Disclosure
G. Adeboyeje: Financial Interests, Personal, Full or part-time Employment: Merck & Co., Inc; Financial Interests, Personal, Stocks/Shares: Merck & Co., Inc. M.I. Sierra: Financial Interests, Personal, Full or part-time Employment: Optum; Financial Interests, Institutional, Other, Optum was contracted by Merck to conduct this research.: Merck. A. Bartels: Financial Interests, Personal, Full or part-time Employment: Optum; Financial Interests, Institutional, Other, Optum was contracted by Merck to conduct this research.: Merck & Co., Inc. M. Field: Financial Interests, Personal, Full or part-time Employment: Optum; Financial Interests, Personal, Stocks/Shares: Optum; Financial Interests, Institutional, Other, Optum was contracted by Merck to conduct this research.: Merck & Co., Inc. S. Jhamb: Financial Interests, Personal, Full or part-time Employment: Optum; Financial Interests, Institutional, Other, Optum was contracted by Merck to conduct this research.: Merck & Co., Inc. A. Buikema: Financial Interests, Personal, Full or part-time Employment: Optum; Financial Interests, Personal, Stocks/Shares: Optum; Financial Interests, Institutional, Other, Optum was contracted by Merck to conduct this research.: Merck & Co., Inc. S. Joo: Financial Interests, Personal, Full or part-time Employment: Merck & Co., Inc; Financial Interests, Personal, Stocks/Shares: Merck & Co., Inc.