The presence of cytokeratins, IgA, alphafetoprotein (AFP), beta-Human Chorionic Gonadotropin (HCG), Carcinoembryonic antigen (CEA) and Epithelial Membrane Antigen (EMA) were immunohistochemically researched with a PAP method in 19 cases of endocervical adenocarcinoma. AFP and HCG were always absent, while the low and median molecular weight cytokeratins were present in 18 case (95%). These findings confirm the hypothesis of the tumoral histogenesis from the reserve cell of the endocervical epithelium. In 11 case (60%) there was a strong positivity of IgA in the lymphocytes surrounding the tumor nests, in the neoplastic cells and in the endoglandular secretion: this may represent a sign of an immune response of the patients to the tumoral antigens. CEA was present in 8 cases and EMA in 12 cases, with a unique expression: CEA positive cases showed no evidence of EMA and case with EMA positive cells were negative for the presence of CEA. Only in one case CEA and EMA were contemporaneously present. The possible interpretation of these findings is discussed.