Study of benign breast disease in a population screened for breast cancer.

We are conducting a study to determine whether risk factors associated with specific pathologic subtypes of benign breast disease (BBD) are similar to those for breast cancer and to evaluate the relationship between clinical and mammographic features of BBD. All women participating in the Canadian National Study of Breast Cancer Screening in Vancouver, B.C., Canada (expected 10,000) are invited to complete a questionnaire designed to gather clinical and epidemiologic information on BBD. Preliminary analysis of the first 736 participants indicates that breast pain and/or tenderness is a significant problem which in its severe from is distressing, anxiety provoking, and adversely affecting quality of life. Breast pain and tenderness is also associated with an increased frequency of clinical signs of BBD and of dense mammographic patterns.