The value of DNA image cytometry for the cytological diagnosis of well-differentiated breast carcinomas and benign lesions.

Cytological evaluation of breast diseases can lead to false diagnosis if benign lesions show epithelial atypia or if carcinomas are orthoplasic and well differentiated. In order to determine the potential usefulness of image cytometry for discrimination between benign and malignant breast lesions, we studied 120 Feulgen-stained imprints, half from benign lesions with epithelial atypia and half from well-differentiated carcinomas and determined values of parameters expressing DNA content, morphometry and chromatin texture. Twenty-five out of the 60 carcinoma imprints were found to be DNA-aneuploid and could thus be easily distinguished from benign imprints, as, in our and other authors' experiences, aneuploidy very rarely occurs in benign breast lesions. When the remaining 35 carcinoma imprints were compared with 38 benign lesion imprints, randomly selected from the 60 cases studied, only four cases were misclassified after a linear discriminant analysis; the most discriminant parameters were those expressing the heterogeneity of DNA content and the chromatin texture. Thus, in cases where cytological diagnosis is difficult, image analysis of Feulgen-stained imprints may be a very useful tool for correctly discriminating benign from malignant cases.