[On the role of CEA-monotoring in the diagnosis of colorectal carcinomas and recidivations (author's transl)].

The CEA-radioimmune-test is not a specific tumour-detection test, but will rather serve as an indicator of the therapeutic result, the formation of recurrent tumours and/or metastases. The CEA titer increase precedes the occurrence of clinical symptoms by up to 12 months, so that a symptomatic look can take place earlier. 150 patients with colorectal carcinomas were observed over a period of 3 years. This yielded the following findings in dealing with the CEA test: 1. Radical tumour surgery results in a decrease of CEA level to normal values. -- 2. A postoperative reduction of CEA titer and subsequent re-increase signalize the formation of a local recidivation. -- 3. A rapid increase in the CEA level after postoperatively decreased or constant values indicates the formation of metastases. -- 4. The CEA test will only possess its full informational value for postoperative treatment when the titer has been increased preoperatively. -- 5. A pathological CEA titer is no proof of a malignant disease. -- 6. A normal CEA titer never rules out a malignant disease.