Investigation of the relationship between breast cancer and clinical symptoms of polycystic ovarian syndrome: a case-control study

Background Despite the overlap between the clinical symptoms of polycystic ovary syndrome (PCOS) and many known risk factors for breast cancer, the relationship between PCOS and breast cancer remains unknown. Therefore, this study was conducted with the aim of determining the relationship between breast cancer and the clinical symptoms of PCOS. Method This case-control study was conducted on 285 women with breast cancer and 285 healthy women referred to three centers in Tehran in 2023. Both the case and control groups were matched in terms of age and body mass index. The data collection tool in this study was a researcher-made data registration form, that was completed in person by qualified individuals. A history of PCOS was identified according to the Rotterdam criteria. Data were analyzed using an independent t-test, a chi-square test, and a logistic regression model. Results The mean age of the participants in the case group was 43.05 ± 4.92 years and that of the control group was 42.78 ± 5.06 years. The two groups showed a statistically significant difference in terms of PCOS history (p < 0.001). After adjusting for confounding variables, the logistic regression model showed that women with PCOS had a significantly higher chance of developing breast cancer (OR:3.677, 95%CI:1.529–8.840, P = 0.004) Among PCOS symptoms, women with a history of hirsutism had a higher chance of developing breast cancer (OR:188.2, 95% CI:1.014–4.720, P = 0.046). Conclusion The findings of the present study show that polycystic ovary syndrome is associated with an increased risk of breast cancer.