“Our findings indicate a link between select types of benign breast lesions and the later development of breast cancer,” says Lynn Hartmann, M.D., Mayo Clinic oncologist and lead investigator of the study. “Women who have a breast biopsy that is benign must discuss the possibility of additional risks with their doctors.”

The Mayo team is evaluating various possible risk factors for a later breast cancer, including age at benign biopsy, family history of breast cancer and the pathologic findings of the benign lesion.

Hartmann and her co-investigators were heartened to find convincing evidence that women with the most common, non-proliferative forms of benign findings had no increased risk of developing breast cancer - as long as they did not have a strong family history of breast cancer. However, for proliferative and atypical types, the opposite was true, and these lesions pointed to an increased risk of a future breast cancer, even when the family history of breast cancer was negative. Hartmann and her colleagues say continued studies of this kind are necessary to help understand the process of breast cancer development.

The study population of 9,087 women was drawn from the Mayo Clinic Surgical and Pathology Indices, identifying women ages 18 to 85, who had a biopsy of a benign breast lesion during a 25-year period. Family histories were obtained at time of follow-up and from Mayo medical record questionnaires.

All benign breast samples were evaluated by a breast pathologist unaware of initial diagnoses or patient outcomes and assigned to one of three categories of benign breast lesions - non-proliferative, proliferative and atypical. This information was used to link the risk of subsequent development of breast cancer to specific types of lesions.

MEDICA.de; Source: Mayo Clinic