Utility of trichrome and reticulin stains in the diagnosis of superficial endometriosis of the uterine cervix

Superficial endometriosis of the uterine cervix is a not uncommon lesion an d the cells on the cervicovaginal smear shed from it can be easily mistaken for cervical glandular intraepithelial neoplasia (CGIN). The correct diagn osis can not always be easily made on H&E stained tissue sections unless it is suspected. The endometriotic stroma is often misinterpreted as stromal hypercellularity or postinflammatory fibrosis following erosion or ulcerati on of the cervical mucosa. Moreover, the endometriotic glands may resemble tubo-endometrioid metaplasia of the endocervical glands, This article descr ibes the utility of trichrome and reticulin stains in the diagnosis of supe rficial cervical endometriosis. The absence of abundant thick collagen bund les and the investment of individual stromal cells by a fine reticulin netw ork within the endometriotic foci are characteristic histologic features. T hese findings are not observed in the surrounding normal cervical stroma no r in the usual conditions in the differential diagnosis.