Risk factors for epithelial ovarian cancer in the female population of Belgrade, Serbia: A case-control study

Background/Aim. Ovarian cancer (OC) comprises 3% of all cancers, but it is the fifth most common cause of cancer death in women. The aim of this case-control study was to determine the risk factors for OC in the female population of Belgrade, Serbia. Methods. A total of 80 consecutive patients were enrolled in the study between 2006 and 2008 in two national referral centers for OC in Serbia. The control subjects were recruited during the regular gynecological check-ups in the Public Health Center of the corresponding municipalities. All the study participants were interviewed during their visits to the above mentioned institutions by two physicians using the same questionnaire. In order to analyze the influence of specific exposure to the risk of the disease, we categorized variables according to the cut-off values. Odds ratios (OR) and 95% confidence intervals (95% Cl) were calculated separately for each variable using univariate conditional logistic regression analysis. Results. There were no statistically significant differences in educational level, years of schooling, occupational and employment status between patients with OC and women in the control group. Oral contraceptives use and other contraceptive methods (condoms, mechanical contraceptive devices) were highly statistically significantly more frequent among women in the control group (OR = 0.2, 95% CI 0.1-0.7, p = 0.005; OR = 0.1, 95% CI 0.01-0.5,p = 0.001, respectively). The patients with OC practiced sports for 6.3 +/- 2.1 years, and controls for 11.8 +/- 9.9 years. Sport and recreation activities were statistically significantly protective (OR = 0.2, p = 0.011; OR = 0.4, p = 0.019). Tea consumption on daily basis had a highly statistically significat protective effect (OR = 0.3, p = 0.001). Conclusions. Oral contraceptives use and physical activity were independent protective factors for OC in this study.