Rare case of microglandular-like adenocarcinoma of endometrium

Abstract

This paper focuses on the microglandular-like pattern, a rare pattern of endometrial carcinoma whose appearance resembles microglandular hyperplasia of the endocervix. Its similarity with benign lesions makes diagnosis of this pattern of carcinoma difficult, particularly in minute specimens. Moreover, it raises a question of whether the tumor originates from the uterine corpus or the cervix. Microglandular-like adenocarcinoma of the endometrium may be an individual type of carcinoma or combined with endometrioid or mucinous carcinoma. The immunohistochemical evaluation is recommended for precise diagnosis: microglandular-like adenocarcinoma expresses markers typical for cervical carcinomas (p16, СК17, and carcinoembryonic antigen) and endometrial carcinomas (estrogen, vimentin, and CD10). The presence of foamy macrophages in the stroma of the tumor and intraglandular foci of squamous differentiation help in the differential diagnosis of microglandular hyperplasia of the endocervix. Immunohistochemical evaluation also facilitates differential diagnosis: a negative PAX2 expression and a high mitotic index (Ki-67 10%) indicate a microglandular-like adenocarcinoma.