The value of the CEA test in the diagnosis of metastases of adenocarcinoma of the gastroenteric tract.

Of 174 patients previously resected for gastric, colon or rectal adenocarcinoma, 75 had distant metastases at the time of the first examination and provided information on the specific characters of different types of tumors as regards CEA sensitivity. The remaining 99 cases, all without clinical evidence of disease, showed positive CEA levels in 26 and negative CEA levels in 73. Of the 26 CEA-positive cases, 24 showed clinical signs of metastases in a period of times varying from 1 to 11 months. The remaining 2 cases, although CEA positive at subsequent tests, did not develop clinical metastases and have been disease-free for 5 years after the first test. Of 73 CEA-negative patients, 30 developed metastases: in 17 the clinical appearance of recurrences was preceded by a positive CEA test, while in 13 the CEA test remained negative even with the presence of disease. The remaining 43 cases are still CEA negative and without metastases from 44 to 51 months from the first examination. Altogether, in 22 cases CEA was negative, but the clinical evidence of recurrences was positive, and in these cases 63.6% were undifferentiated carcinomas; 2 patients were CEA positive but without signs of evident metastases.