Static cytometry of DNA in breast lump with reference to grading.

Fresh smears of 400 consecutive cases of breast lumps stained with Feulgen stain were measured with densitometric technique in static cytometry. A correlation was observed between DNA content expressed by the DNA index and histologic grading of malignant lesions; relatively high values were observed in the group of "hyperplasias", which were similar to G1. Values of DNA content in different categories: benign, hyperplastic (nodular and sclerosing adenosis, epitheliosis . . .) and all malignant types variously graded in G1, G2 and G3, show broad areas of overlapping, suggesting that the parameter is not always discriminating between benign, hyperplastic and malignant, but it can identify different amounts of DNA (high and low degrees) within a homogeneous category. Correlation between number of hypertetraploid nuclei (4c) and histologic grading was also evident. Therefore, fresh smears, in relation to DNA content and to the percentage of hypertetraploid elements allow a better definition of "high and low degree" lesions in a short time with possible prognostic involvement as regards tumoral progression.