Year 1: Experiences of a tertiary cancer centre following implementation of reflex BRCA1 and BRCA2 tumor testing for all high-grade serous ovarian cancers in a universal healthcare system

Abstract

Objective: This study compares the rate and time to genetic referral, and patient uptake of germline genetic services, before and after implementation of reflex BRCA1/2 tumor testing for high-grade serous ovarian cancer (HGSOC) in a universal healthcare system.

Methods: A retrospective chart review of HSGOC patients diagnosed in the year before (PRE) and after (POST) implementation of reflex BRCA1/2 tumor testing was conducted. Clinical information (date/age at diagnosis, personal/family history of breast/ovarian cancer, cancer stage, primary treatment, tumor results) and dates of genetics referral, counseling, and germline testing were obtained. Incident rate ratios (IRR) and 95% CI were calculated using negative binomial regression. Time to referral was evaluated using Kaplan-Meier survival analysis. Fisher Exact tests were used to evaluate uptake of genetic services.

Results: 175 HGSOC patients were identified (81 PRE; 94 POST). Post-implementation of tumor testing, there was a higher rate of genetics referral (12.88 versus 7.10/1000 person-days; IRR = 1.60, 95% CI: 1.07-2.42) and a shorter median time from diagnosis to referral (59 days PRE, 33 days POST; p = .04). In the POST cohort, most patients were referred prior to receiving their tumor results (n = 63/77; 81.8%). Once referred, most patients attended genetic counseling (94.5% PRE, 97.6% POST; p = .418) and pursue germline testing (98.6% PRE; 100% POST; p = .455).

Conclusions: Following implementation of reflex BRCA1/2 tumor testing for HGSOC, significant improvements to the rate and time to genetics referral were identified. Additional studies are needed to evaluate physician referral practices and the long-term impact of reflex tumor testing.

Keywords: BRCA; Genetic counseling; Genetic testing; Ovarian cancer; Service delivery.