Nationwide Swedish cohort study of risks of non-ovarian cancer malignancies among women with borderline ovarian tumor

A nationwide cohort study in Sweden investigated the risk of simultaneous or subsequent non-ovarian cancer malignancies among women with a diagnosis of borderline ovarian tumor (BOT). Compared to the general female population in Sweden, BOT patients had increased risks of cancers of the colon, rectum, small intestine, cervix, endometrium, pancreas, upper aerodigestive tract, lung, kidney, and bladder. Among women with serous BOT, the risk of thyroid gland cancer was also increased. Lung and pancreas cancer showed increased risks more than 1 year after BOT diagnosis. The authors conclude that these results suggest a potential shared etiology of BOT and other cancers.