[Ultrastructure of foamy and pigmented cells in the female breast]

Electronmicroscopy was performed on 5 surgical specimens from the mammary gland of 21-, 34-, 49-, 49-, and 51-years-old women. Histological diagnosis of mammary dysplasia was established in all of patients. Ultrastructure of foamy cells showed lipid vacuoles without obvious limiting membrane, lysosomal vacuoles with annulate and vesiculate membranous structures, lamellar bodies and lipofuscin inclusions which prevailed in pigmented cells. There were only quantitative differences between both types of cells. Neither phagocytosis nor another feature of macrophagic origin were found. On the contrary, epithelial origin of these cells could be conceded according to the finding of desmosomes among foamy cells in ductal lumina. But periductal cells apparently could be derived from stromal cells.