Still room for improvement: patterns and missed opportunities over a decade in BRCA testing

Abstract

Objectives: The criteria for and access to genetic testing (GT) for patients with increased risk of cancer has expanded over the last decade. The objective of this study was to explore patterns of BRCA testing for patients over the last decade at our institution. Methods: This is a retrospective cohort study at three satellite sites within one institution. Patients were identified by ICD-10 codes associated with hereditary disposition of malignancy (Z15.01, Z15.02, Z15.09, Z15.89, C50.919, Q99.8, C54.1). Inclusion criteria were patients with BRCA1 and BRCA2 pathogenic mutations who underwent genetic testing between 2009-2018. Patients with unknown BRCA1/2 status, variants of unknown significance, and unknown dates of genetic testing were excluded. Patients who underwent GT between 2009-2013 (early) were compared to those who underwent testing between 2014-2018 (late). These time periods were chosen based on GT practice changes around this time including lifting of BRCA patent and implementation of universal ovarian cancer GT. Outcomes of interest were the rates of patients diagnosed with BRCA mutations after their cancer diagnoses. Kruskal-Wallis and chi-square tests of independence were performed. Results: Five hundred forty-six patients met inclusion criteria; 197 (36%) underwent BRCA testing between 2009-2013, and 349 (64%) between 2014-2018. Median age at testing was 40 (range 19-90) with no significant differences over time (p=0.093). Thirty one percent in our cohort of BRCA1/2 patients had a diagnosis of breast cancer, 8.6% with ovarian and 1.3% with uterine cancer. Patients in the earlier time cohort were more likely to have a personal history of breast cancer (37% vs 28%, p=0.02), but there were no differences in patients with ovarian cancer over time (p=0.761). There were no significant differences between the two time periods in regards to reasons for GT (personal history of cancer, family history of known mutation, family history of cancer). Of 220 patients with a personal history of cancer and known dates of cancer diagnosis, 153 (67%) underwent genetic testing after a diagnosis of cancer, with no difference between our time periods of interest (63% vs 74%, p=0.081). Patients in the later time cohort were less likely to undergo risk-reducing mastectomy (49% vs 30%, p Download : Download high-res image (190KB) Download : Download full-size image Conclusions: Despite increases in GT over time, over 2/3 of patients with BRCA mutations still undergo testing after a personal diagnosis of cancer. Despite expansion of testing platforms and indications for testing, no improvement in GT prior to development of cancer was noted over time. Efforts targeted at education for earlier recognition for GT by family history and cascade testing are critical; testing for BRCA prior to development of cancer to enable active screening and prevention ovarian cancer is of utmost importance.