[Aneuploidy in focal adenomatosis as a risk factor for the development of breast cancer].

The study of the DNA content in nuclei of the mammary gland epithelium in 18 females with fibroadenomatosis, followed by breast cancer, and in 47 patients showing fibroadenomatosis, but no cancer subsequently, indicated that the presence of aneuploid cells in fibroadenomatous foci may be regarded as one of high risk factors of breast cancer incidence. In these patients the risk for breast cancer is 9 times as that in the remaining subjects with fibroadenomatosis.