Ploidy level of human breast carcinoma. Relation to histopathologic features and hormone receptor content.

The ploidy level was investigated by flow cytometric analysis in 143 cases of invasive intraductal mammary carcinoma. Aneuploidy was found in 70% of the tumours. Comparison of ploidy level with histopathologic features, hormone receptor status and clinical characteristics indicated that aneuploid tumours were mostly poorly differentiated (grade III) and oestrogen receptor negative (p less than 0.05). However, this applied only to postmenopausal patients. No correlation appeared between the progesterone receptor status and the ploidy level, but this parameter tended to predict the frequency of lymph node metastases. The possible prognostic significance of these findings is discussed.