Immunohistochemical demonstration of HNK-1-defined antigen in gynecologic tumors with argyrophilia.

Gynecologic tumors with argyrophilia were tested immunohistochemically for reactivity with monoclonal antibody HNK-1, which detects normal and neoplastic cells derived from the neuroectodermal and the amine-precursor-uptake and decarboxylation (APUD) systems. The tumors included six small cell carcinomas and four adenocarcinomas of the cervix; 23 adenocarcinomas of the endometrium (13 with type I and 10 with type II argyrophil cells); and 11 mucinous tumors (three benign, three borderline, and five malignant), eight endometrioid carcinomas (four with type I and four with type II argyrophil cells), and two carcinoid tumors (one insular and one strumal) of the ovary. HNK-1 reactive cells were found in almost every category of tumor: in four small cell carcinomas and two adenocarcinomas of the cervix; 11 adenocarcinomas of the endometrium (eight with type I and three with type II argyrophil cells); and four mucinous (two benign and two borderline), two endometrioid (one with type I and one with type II argyrophil cells), and two carcinoid tumors of the ovary. These cells corresponded to at least some of the type I argyrophil cells in endometrial and ovarian endometrioid carcinomas and to similar cells in mucinous and carcinoid tumors of the ovary and small cell carcinoma and adenocarcinoma of the cervix. However, the remaining type I and similar argyrophil cells and almost all type II argyrophil cells were HNK-1 negative, and some of the nonargyrophil tumor cells were HNK-1 positive. Although the significance of such discrepancies in reactivity with HNK-1 antibody remains unknown, the present results suggest that some of the gynecologic tumors with argyrophilia are related to APUDomas.