Adenocarcinoma of the Fallopian tube. An ultrastructural study.

A case of fallopian tube adenocarcinoma was studied by light and transmission electron microscopy. The neoplastic cells contained abundant mitochondria, moderate to large amounts of rough endoplasmic reticulum (RER) arranged in parallel arrays and often containing amorphous material, annulate lamellae, possible secretory vesicles, and glycogen. The presence of stacked RER and annulate lamellae together is unusual in papillary serous cystadenocarcinoma of the ovary, and has not been described in Fallopian tube adenocarcinoma. Golgi complexes were are. Small acini with projecting microvilli as well as junctional complexes were present, but cilia were not found. The electron microscopic findings suggest secretory activity, and are remarkably similar to those found in papillary serous cystadenocarcinomas of the ovary. The findings also support the hypothesis that ovarian serous tumors and adenocarcinomas of the Fallopian tube are derived from coelomic epithelium.