INTRODUCTION: The disclosure of genetic testing (GT) results is a complex process. The NCCN Genetic/Familial High- Risk Assessment: Breast, Ovarian, and Pancreatic Guidelines (v1.2020) recommend GC as a fundamental component of the GT process. With the changing landscape of cancer genetics, particularly for pts with metastatic breast cancer and a gBRCA1/2 mutation, understanding the extent to which GC is integrated into pt care in those undergoing GT is important. This study assessed real- world GC patterns among US adult pts with gBRCA1/2mut ABC.
METHODS: Oncologists (ONC) retrospectively reviewed charts (Jul- Oct 2019) of quasi- random selected pts ≥18yrs, with gBRCA1/2mut ABC who received ≥1 cytotoxic chemotherapy regimen(s) for ABC between Jan 2013- Apr 2018. Pts were categoriz ed into mutually exclusive categories based on practice setting. Differences in GT patterns by practice settings were compared using χ2 or Fisher’s exact test.
RESULTS: 225 pts were included: 99.6% female, 78.2% white. Median age at diagnosis of ABC was 57.7 years, 25.8% had no known family history of a BRCA- related cancer. Tumor characteristics: 78.7% HER2- , 21.3% HER2+ disease. 82.7% of pts received GC (18.2% pre- test only, 24.0% post- test only, 40.4% both pre- and post- test). A fewer proportion of pts who received care by community ONC were known to received GC (80.4%) vs academic ONC (90.6%; P =0.03). Among pts who received GC, genetic counselors (78%) most commonly provided this service, followed by ONC (21.5%) and other professionals (0.5%). Pts who received care by community ONC were more likely to receive GC from their ONC (33.3%) vs pts receiving care by an academic ONC (10.4%; P <0.01). Overall, mode of counseling included face- to- face (89.1%) and phone/internet (10.9%). Among pts who received GC by genetic counselors, phone/internet- based counseling was higher for pts who received care by community ONC (18.6%) vs pts who received care by an academic ONC (10.7%; P = 0.22).
CONCLUSIONS: US guidelines recommend that all pts with hereditary cancers receive GC as effective communication may eliminate barriers of understanding the implications of GT results. In this real- world study, disparities in GC were observed with fewer pts receiving GC when treated by a community ONC (vs at academic centers). Limited access to GC (due to geographic barriers, or long wait times due to critical shortage) may have contributed to this observation. Use of technological resources (e.g. telemedicine services) may be an opportunity to make GC more readily available.