Association of benign gynaecological diseases and risk of endometrial and ovarian cancers

Objective: Gynaecologic benign diseases such uterine fibroids share similar pathogeneses with endometrial and ovarian cancers. Whether a history of uterine fibroids increases the risk of developing endometrial or ovarian cancers is controversial, due to uterine fibroids was self-reported in those studies. Methods: In our current case-control study, 268 women with endometrial cancer and 108 women with ovarian cancer were included. In addition, 500 women without gynaecological cancers were randomly selected as a control group. Uterine fibroids in both groups were clinically diagnosed by pelvic examination and ultrasound. Data on age, parity, gravida, stages of cancers and history of uterine fibroids, endometriosis and adenomyosis were collected from hospital database. Results: After adjusted age and parity, the odds of women with history of uterine fibroids or endometriosis were lower in women with endometrial cancer than controls (odds ratio: 0.148, 95% CI: 0.097, 0.225, or 0.360, 95% CI: 0094, 1.381, respectively). The odds of women with a history of uterine fibroids or endometriosis were lower in women with ovarian cancer than controls (odds ratio: 0.141, 95% CI: 0.085, 0.235, or 1.057, 95% CI: 0.377, 2.963, respectively). However, the odds of women with a history of adenomyosis were higher in women with endometrial or ovarian cancers than controls (odd ratio: 3.757, 95% CI: 1.858, 7.599 or 2.341, 95% CI: 1.086, 5.045, respectively). Conclusion: Our observational data suggested that uterine fibroids or endometriosis may be not associated with the increased risk of developing endometrial or ovarian cancer. However, a history of adenomyosis may do.