Immunohistochemical analysis of clear cell carcinoma of the gynecologic tract

Clear cell carcinoma of the gynecologic tract has been defined in terms of its clinical and histologic features; however, its immunophenotypic profile has not been fully characterized. Seventeen cases of primary clear cell ca rcinoma from various sites within the female genital tract (11 ovary, 5 ute rus, 1 vagina) were analyzed by immunohistochemistry. These turners were as sessed for the expression of cytokeratin 7 (CK7), cytokeratin 20 (CK20), lo w and high molecular weight cytokeratins (CAM5.2 and 34 beta E12, respectiv ely), carcinoembryonic antigen (CEA), Leu-MI, vimentin, estrogen receptor ( ER), progesterone receptor (PR), bcl-2, p53, HER-2/neu, and CA-125. The cha racteristic immunoprofile for all sites was positivity fur CK7, CAM5.2, 34 beta E12, CEA, Leu-Ml, vimentin, bcl-2, p53, and CA-125; variably positivit y for ER and HER-2/neu; and negativity for CK20 and PR. For comparison, two cases of urologic clear cell carcinoma (1 bladder, I urethra) were also st udied, and their profile was found to be similar to the gynecologic cases. Aside from minor differences, clear cell carcinoma appears to have the same immunophenotype regardless of whether it originates in the endometrium, ov ary, or genitourinary tract. Much of its profile is similar to other gyneco logic adenocarcinomas, but some of the markers studied may be useful in the differential diagnosis of this tumor.