Human prostatic carcinoma: an electron microscope study.

Electron microscopic studies of human prostatic cancers revealed that cytologically well-differentiated and poorly differentiated tumor cells are present in both histologically well-differentiated and anaplastic prostatic cancers. Secretory and enzyme (acid phosphatase) activity in the cancer cell is dependent on cytologic differentiation; the latter bears no constant relation to histologic differentiation of the tumor. The amount of well-differentiated tumor cells in a given cancer determines the degree and intensity of acid phosphatase activity in the tumor. The presence of poorly differentiated tumor cells and their generally diminished secretory activity account for the diminished acid phosphatase activity (histochemically and biochemically) often observed in prostatic cancers. Basement membranes are present, although often incompletely, around the cancer acinus and even around individual cancer cells. Outstanding features of prostatic cancer cells, when compared to normal and hyperplastic prostatic epithelial cells, are the nuclear hypertrophy, hyperchromatinism, nucleolar hypertrophy, increase in number and pleomorphism of mitochondria, greater amount of free ribosomes, variability of position of Golgi apparatus, and increased amount of lipid droplets of variable morphology. The significance of these features, and the differentiation of cancer cells in relation to production and secretion, particularly that of acid phospatases and its level in the serum, are discussed.