Papillary cystadenofibroma of endometrium: a histochemical and ultrastructural study.

The light and electron microscopic as well as the histochemical characteristics of a papillary cystadenofibroma of the endometrium are described. The neoplasm arose in the lower uterine segment and was composed of a florid fibroblastic growth arranged in club-shaped papillae projecting into clefts and cystic spaces. The epithelium lining the plicae, recesses, and cysts was exclusively of the mucous-secreting type and bore identical histochemical and subcellular characteristics to that of the normal endocervical epithelium. Essentially similar papillary lesions were recently reported in the endocervix, endometrium, and fallopian tube. The pathogenesis and differential diagnosis of this distinct neoplasm are discussed in the light of the available morphological data.