The present status of DEA in diagnosis, prognosis, and evaluation of therapy.

Despite nonspecificity for the diagnosis of colon cancer, the assays for CEA widely studied to date may be useful in the management of patients with colorectal cancer by aiding detection of colonic cancer and especially of widespread metastases to the liver. Use of serial quantitative measurements may also be useful in determining persistence of residual or metastatic tumor after apparently complete surgical resection, in enabling detection of recurrence at an earlier stage than may be otherwise possible, and in helping to evaluate the effects of chemotherapy, provided that the assays are used only in context with complete clinical and laboratory findings, including cancer staging, histopathologic findings, assessment of liver status, and with appreciation of methodologic complexities. Both the further investigation of the clinical use of CEA and the intensified search for more specific markers are encouraged by the findings to date.