Proliferative disorders of the breast as risk factors for breast cancer in a self-selected screened population: pathologic markers.

A study was done to quantify the pathologic risk of subsequent breast cancer in women whose biopsies demonstrated proliferative histologic conditions. Out of a total of 10,530 patients, 1,408 had biopsies which were classified as either bland fibrocystic or hyperplastic. The behavior of the disease in these patients was compared to that of the general screened population. It was concluded that women whose biopsies reveal hyperplastic disorder, primarily atypical hyperplasia and fibroadenoma, run the greatest risk of getting cancer. For women with atypical hyperplasia, the risk is 13 times that of the general population, and for those with fibroadenoma it is three times greater.