Background: Despite the fact that breast cancer is the most common female cancer worldwide, more than half of the breast cancer risk factors remained unexplained. The aim of this study was to investigate the association of cigarette smoking with risk of breast cancer.
Materials and methods: A case-control study was conducted in the Clinical Centre of Kragujevac, Serbia, covering 382 participants (191 cases and 191 controls). In the analysis of data logistic regression was used.
Results: Breast cancer risk was significantly increased in those who quit smoking at ≤ 50 years of age (OR=2.72; 95% confidence interval - 95%CI=1.02-7.27) and in those who quit smoking less than 5 years before diagnosis of the disease (OR=4.36; 95%CI=1.12-16.88). When smokers were compared with nonsmokers without passive exposure to smoking, former smoking significantly increased breast cancer risk (OR=2.37; 95%CI=1.07-5.24). Risk for breast cancer was significantly increased in those who quit smoking at ≤ 50 years of age (OR=3.29; 95%CI=1.17-9.27) and in those who quit smoking less than 5 years before diagnosis of the disease (OR=5.46; 95%CI=1.34-22.28).
Conclusions: These data suggest that cigarette smoking is associated with an elevated risk of breast cancer among former smokers in Serbia.