The Burden of Cancers Associated with Hereditary Breast and Ovarian Cancer Syndrome, 2015-2019: A Population-based...

Hereditary breast and ovarian cancer syndrome (HBOCS) is an inherited condition that increases the risk of developing several types of cancer; however, the true burden of HBOCS-related cancers remains unclear at the population level.

We used 2015-2019 breast and ovarian cancer data (N=55,437) from the New Jersey State Cancer Registry to estimate the age-adjusted incidence of HBOCS-related breast and ovarian cancers in New Jersey, overall and by county. Cancers meeting 5 HBOCS diagnostic characteristics selected from the 2021 National Comprehensive Cancer Network risk assessment guidelines were flagged as possibly being HBOCS-related and referred to as "possible-HBOCS (pHBOCS)." We evaluated the racial/ethnic and stage patterns of HBOCS cancers and compared them to all cancers to further characterize the HBOCS burden. Age-adjusted incidence rates (AAIR) per 100,000 population, rate ratios (RR), and 95% confidence intervals (CI) were computed using the Surveillance, Epidemiology, and End Results Program (SEER) *Stat Database.

We identified 12,679 pHBOCS cancers among NJ residents from 2015-2019. The female AAIR of pHBOCS breast and ovarian cancers was 50.6 per 100,000 population. The rates of pHBOCS varied by county, and pHBOCS county rates varied by race. Among Hispanic women, the incidence was significantly higher in Hunterdon County (AAIR 115, 95% CI:68.4-181.1) than statewide (AAIR 40.6, 95% CI:38.7-42.6). The pHBOCS incidence was significantly lower for Asian/Pacific Islander (RR=0.85, 95% CI:0.80-0.91), Hispanic (RR=0.74, 95% CI:0.70-0.79), and non-Hispanic Black women (RR=0.90 95% CI:0.85-0.95) than non-Hispanic White women. Compared to local-stage ovarian cancers, the incidence of distant-stage was significantly higher in the overall cancer population (RR=2.59, 95% CI:2.37-2.83) and the pHBOCS cancers (RR=3.22, 95% CI:2.93-3.55). The rate of regional-stage ovarian cancers was only significantly higher than local for the pHBOCS group (RR=1.21, 95% CI:1.08-1.36).

This study can be used as a starting point for building a framework that better estimates the population burden of HBOCS cancers. Quantifying the HBOCS impact improves our understanding of the true burden. Due to data availability limitations, true estimates could not be calculated. Policies supporting population-level, genetic/family history data collection are needed to accurately quantify HBOCS incidence.