Extensive Epithelioid Cell Granulomatous Reactions to Esophageal and Gastric Carcinomas : Immunohistochemical Investigations of Four Cases

Four cases of extensive epithelioid cell granulomatous reaction occurring in two gastric and two esophageal cancer patients are presented. Non-caseating epithelioid cell granulomas (NCEG) developed not only in the regional lymph nodes but within and widely around the primary tumor in all cases. NCEG also involved the spleen in one patient with early gastric cancer. The epithelioid cells directly infiltrated inside the tumor and obliterated cancer cells in one patient with esophageal cancer, the findings demonstrating histologic evidence that those cells have the ability to kill cancer cells. Three patients manifested the same immune alterations as those in sarcoidosis. Thus, NCEG associated with cancer are considered a morphological manifestation of the host immune response to cancer, most likely developing in the lymphoid organs. The extensive manifestation of such changes may develop under the altered immune conditions