Detection of Carcinoembryonic Antigen in the Media of Cultures of Carcinomatous Cells of Digestive-System Origin

A radioimmunoassay technique was used to detect carcinoembryonic antigen (CEA) in the media of cultured cells from various human cancers. Of 6 adenocarcinomas of the colon or rectum, 4 gave positive results, with high titers; 1 of 7 breast carcinomas and 1 parotid carcinoma reacted positively, with borderline titers. Of 8 melanomas and 11 other neoplasms fested, none was positive. One colon carcinoma had high titers, even after 31 days in culture.