Polycystic ovarian syndrome (PCOS), related symptoms/sequelae, and breast cancer risk in a population-based case–control study

Abstract

Purpose Despite the overlap between the clinical symptoms/sequelae of polycystic ovarian syndrome (PCOS) and many known reproductive risk factors for breast cancer, the relationship between PCOS and breast cancer remains unclear, possibly because of the complex heterogeneity and challenges in diagnosing PCOS over time. We hypothesized that PCOS, specific PCOS-related symptoms/sequelae, or clusters of PCOS-related symptoms/sequelae, may be differentially associated with pre- vs. postmenopausal breast cancer risk. Materials and Methods Cases were 1,508 women newly diagnosed with a first primary in situ or invasive breast, and the 1,556 population-based controls were frequency-matched by age. Results History of physician-diagnosed PCOS was reported by 2.2% (n=67), among whom oral contraceptive (OC) use, irregular menstruation, and infertility due to ovulatory dysfunction were common. Using unconditional logistic regression, adjusted odds ratios (95% confidence intervals) for PCOS were increased for premenopausal [2.74 (1.13, 6.63)], but not post-menopausal breast cancer [0.87 (0.44, 1.71)]. We used cluster analysis to investigate whether risk among all women varied by PCOS-related symptoms/sequelae, such as reproductive irregularities, OC use, and components of insulin resistance. In the cluster analysis, odds ratios were elevated among premenopausal women who had a history of OC use and no ovulatory dysfunction [1.39 (1.03, 1.88)], compared to those with fewer number of PCOS-related symptoms/sequelae. Conclusion PCOS, and associated PCOS-related symptoms/sequelae including OC use, may play a role in the development of premenopausal breast cancer. Our findings require confirmation in studies with a larger number of premenopausal women with systematically applied diagnostic criteria for PCOS.

The risk of breast and gynecological cancer in women with a diagnosis of infertility: a nationwide population-based study

“…It is possible that the risk reported by Jensen et al was influenced by factors such as higher age at first birth among infertile women. Most previous studies have presented SIRs adjusted only for age and calendar year, which could explain why the risk of breast cancer was found higher in some of them [ 15 , 17 , 28 – 30 ]. It is reasonable to assume that parity and age at first birth act as mediators rather than confounders in the studied association.…”

Female infertility, infertility-associated diagnoses, and comorbidities: a review

“…An analysis of publications shows that women with infertility had higher rates of psychiatric disorders and endometrial cancer than the general population [1][2][3][4][5][6][7][8][9][10]. Data is conflicting about whether infertile women are at increased risk for breast cancer and ovarian cancer [7,8,[10][11][12][13][14][15][16][17][18][19][20]. A generalized diagnosis of infertility was not clearly associated with an increased risk of cardiovascular disease or metabolic dysfunction, but women with infertility related to polycystic ovarian syndrome (PCOS) do appear more likely to develop cardioCapsule There is a growing body of literature addressing the impact of female infertility on long-term health.…”

Polycystic Ovarian Syndrome: Long-Term Health Consequences

“…A study by Kim et al identified more than 1,500 women with newly diagnosed in situ or invasive breast cancer and compared them to age-matched controls. 65 Approximately 2.2% of the population reported having a PCOS diagnosis established by a medical professional and the remainder reported no PCOS or were unsure, 96.3 and 1.5%, respectively. The women diagnosed with PCOS were more likely to have used OCs, to have a history of infertility, and to not have regular cycles.…”