Breast cancer risk factors: PCB congeners

The chronic effects of polychlorinated biphenyls (PCBs) are a public health concern, and a potential relationship with breast cancer has been postulated. The purpose of this study was to examine the possible relationship between PCBs and breast cancer. All women (134) treated by excision biopsy because of breast lump at Reina Sofia University Hospital, Cordoba, Spain over a period of 10 months were included in our study. They were all administered a questionnaire by interview, calculation of body mass index, histopathological examination of excised mass and chemical estimation of PCB congener levels in breast fat. The collected samples were from 65 (48.5%) women with benign lesions and 69 (51.5%) with malignant lesions. The variables associated with malignant lesions on univariate analysis were age, lactation period, overweight, PCB n-28 and PCB n-52. On the multivariate analysis PCB n-28 was found to be the most important risk factor (OR 9.6, 95% CI 3.8-24.4). Other risk factors were identified as age, drinking alcohol, low parity and overweight. If these findings can be confirmed in a large study population, however, they may have important implications for breast cancer risk.