Physical Activity During Adolescence and Early-adulthood and Ovarian Cancer Among Women with a BRCA1 or BRCA2 Mutation

In the general population, physical activity has been associated with a lower risk of several cancers; however, the evidence for ovarian cancer is not clear. It is suggested that early-life physical activity may differentially impact risk. Whether this is true among women at high risk due to a pathogenic variant (mutation) in the BRCA1 or BRCA2 genes has not been evaluated. Thus, we performed a matched case–control study to evaluate the association between adolescent and early-adulthood physical activity and ovarian cancer. BRCA mutation carriers who completed a research questionnaire on various exposures and incident disease and with data available on physical activity were eligible for inclusion. Self-reported activity at ages 12–13, 14–17, 18–22, 23–29, and 30–34 was used to calculate the average metabolic equivalent of task (MET)-hours/week for moderate, vigorous, and total physical activity during adolescence (ages 12–17) and early-adulthood (ages 18–34). Conditional logistic regression was used to estimate the OR and 95% confidence intervals (CI) of invasive ovarian cancer associated with physical activity. This study included 215 matched pairs (mean age = 57.3). There was no association between total physical activity during adolescence (OR(high vs. low) = 0.91; 95% CI: 0.61–1.36; P(trend) = 0.85), early-adulthood (OR(high vs. low) = 0.78; 95% CI: 0.51–1.20; P(trend) = 0.38) and overall (OR(high vs. low) = 0.81; 95% CI: 0.54–1.23; P(trend) = 0.56) and ovarian cancer. Findings were similar for moderate (P(trend) ≥ 0.25) and vigorous (P(trend) ≥ 0.57) activity. These findings do not provide evidence for an association between early-life physical activity and BRCA-ovarian cancer; however, physical activity should continue to be encouraged to promote overall health. SIGNIFICANCE: In this matched case–control study, we observed no association between physical activity during adolescence or early-adulthood and subsequent risk of ovarian cancer. These findings do not provide evidence for an association between early-life physical activity and BRCA-ovarian cancer; however, being active remains important to promote overall health and well-being.