Monstrous epithelial cells in human epididymis and seminal vesicles. A pseudomalignant change.

Peculiar monstrous epithelial cells simulating anaplastic malignant transformation were observed in human epididymis and seminal vesicles. In epididymis, scattered hyperchromatic giant epithelial cells were seen protruding into the lumina of ductuli efferentes in 12 of 43 specimens examined (28%). Eight cases were seen in cancer patients and four cases in noncancer patients. In seminal vesicles, epithelial cells exhibiting nuclear hypertrophy, hyperchromatism, and transformation into a variety of grotesquely shaped nuclei were observed in 24 of 32 specimens examined (75%). Fourteen cases were seen in cancer patients and 10 cases in noncancer patients. Since the peculiar epithelial changes were observed in both cancer and noncancer patients, this phenomenon represented a histologically pseudomalignant condition. In both organs, the group of patients without atypical epithelial changes were younger. Generally, the pseudomalignant changes were not seen in persons under the age of 20. There was no correlation to any particular systemic disease. The histogenesis remains speculative, but hormonal effects or degeneration due to aging seem to be contributory. The most important aspect of these observations, however, is that the changes described should not be mistaken for cancer. In addition, eosinophilic hyaline bodies were frequently observed in the muscle layer of seminal vesicles. The nature and the significance of their occurrence is unknown.