Adenoid basal carcinoma of the uterine cervix: immunohistochemical study and literature review.

Adenoid basal carcinoma of the uterine cervix is rare and its cell origin is still obscure. We report a case of adenoid basal carcinoma of the uterine cervix discovered incidentally in a 69-year-old woman who had been hysterectomized due to endometrial adenocarcinoma of the uterine corpus. Histologically, small round-to-oval cancer cell nests with peripheral cell palisading were seen budding from the basal cell layer of the uterine cervix showing carcinoma in situ. Immunohistochemically, the basaloid cells of the adenoid basal carcinoma were positive for keratins 14, 17 and 19 and resembled reserve cells of the cervical epithelium. The results of this study clearly demonstrated that adenoid basal carcinoma shows a phenotype similar to reserve cells of the uterine cervix. A review of the literature indicated that this tumor has a favorable prognosis and should be clearly separated from adenoid cystic carcinoma, which has a much poorer outcome.