This study investigated the associations between benign breast disease and breast cancer in a population including a substantial fraction of African-American women. The study included women who had been diagnosed with benign breast disease based on an excisional breast biopsy. Women with proliferative lesions (no atypia, risk level 2) were found to be 1.7 times more likely to develop breast cancer than women with non-proliferative lesions, whereas women with atypia (risk level 3) were 3.75 times more likely to progress to breast cancer. However, participants with fibroadenoma (nonproliferative or proliferative) were less likely to progress to breast cancer. In addition, African-American women over 50 were found to be at greater risk for progression to breast cancer from benign breast disease than younger, non-African-American women.

Implications for breast cancer prevention

This study confirms the findings of other studies that have reported that a diagnosis of benign breast disease is associated with higher risk of subsequent breast cancer. Benign breast disease has been shown to have a heritable component and this study suggests that African-American women may be more susceptible to progression to breast cancer.

A diet rich in fruits and vegetables has been found to be associated with reduced risks of proliferative and atypical breast lesions. We suggest consuming a wide variety of fruits and vegetables from our recommended food list. Studies have also reported that women with benign breast disease can reduce their risk of progression to breast cancer by increasing consumption of marine omega-3 fatty acids (found in salmon, herring and other fatty fish). On the other hand, consumption of coffee and caffeine, alcohol, and soy supplements containing the isoflavones genistein and daidzein have been found specifically to increase the risk of breast cancer for women with benign breast disease.