Evaluation of BRCA1/2 testing rates in epithelial ovarian cancer patients: lessons learned from real-world clinical data

TL;DR

This study evaluates BRCA1/2 testing rates in ovarian cancer patients in the Netherlands, finding disparities in access and suggesting ways to improve testing.

Contribution

The study provides insights into real-world BRCA1/2 testing practices and identifies factors influencing test completion in epithelial ovarian cancer patients.

Findings

69.8% of EOC patients completed the BRCA1/2 test-pathway over four years.

Younger patients and those with high-grade tumors were more likely to complete testing.

Inequalities in testing access were observed among older and lower socioeconomic status patients.

Abstract

Identification of somatic and germline BRCA1/2 pathogenic variants in epithelial ovarian cancer (EOC) patients is essential for determining poly-(ADP-ribose)-polymerase (PARP) inhibitor sensitivity and genetic predisposition. In the Netherlands, BRCA1/2 testing changed to a tumor-first approach to efficiently identify both somatic and germline pathogenic variants in all patients. Here, we performed an in-depth evaluation of the first four years of the tumor-first test-pathway. Data of consecutive series of patients diagnosed with EOC in two regions were obtained from the Netherlands Cancer Registry. Tumor and/or germline test data were retrieved from hospital databases. The primary outcome was the percentage of patients completing the BRCA1/2 test-pathway, defined as having a negative tumor test or a referral for a germline test in case of a positive tumor test or no tumor test. Factors associated with test-pathway completion were identified through multivariable logistic regression analysis. In total, 69.8% (757/1085) completed the test-pathway. This was 74.4% in the most recent year. Younger patients, patients diagnosed in year three or four, patients with high-grade serous/high-grade endometrioid carcinoma, advanced stage disease, middle or high socioeconomic status, and patients who underwent surgery or chemotherapy, were more likely to complete the test-pathway. We report inequalities in genetic testing access in EOC patients, which highlight the need for better guideline adherence, particularly in older patients, those with low socioeconomic status, low-grade histotypes, early-stage disease and those without surgery or chemotherapy. Additionally, timely testing of patients, and testing relatives if patients cannot be tested, are crucial to increase test uptake.

The online version contains supplementary material available at 10.1007/s10689-025-00467-7.

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