Immunohistochemical study of possible changes in keratin expression during neoplastic transformation of the uterine mucosa.

The present study aimed to examine possible changes in keratin expression during neoplastic transformation of the uterine mucosa and possible differences in keratin expression between endocervical and endometrial adenocarcinomas. Routinely processed specimens with normal morphology or neoplastic changes were stained immunohistochemically using 5 commercial antibodies to keratin-filaments of molecular weight 39-58 kD: CAM 5.2, RCK 102, MCA 144, PKE and PRE. We generally found a change in keratin expression during the neoplastic transformation, consisting of pronounced heterogeneity compared with normal epithelia. In distinguishing koilocytic atypia from CIN, RCK 102 (52.5, 58 Kd) may prove helpful as it stains neoplastic cells strongly and shows no reaction in koilocytic. Staining with the antibody CAM 5.2 (reactive with 39, 43, 50 kD filaments) may aid in distinguishing between cervical and endometrial adenocarcinomas. The former is stained uniformly; the latter shows a more variable staining.