The contribution of serum enzymes and carcinoembryonic antigen to the early diagnosis of metastatic colorectal cancer.

The evolution of metastatic colorectal cancer in patients who have had surgical treatment for a primary lesion was studied in relation the progressive changes in the blood levels of carcinembryonic antigen (CEA), to gamma glutamyl transpeptidase (GGT) and routine liver function tests (LFTs). Involvement of the liver could ofter be reliably predicted many weeks in advance of clinical diagnosis while metastases to other sites were less likely to be detected early by this test. The association of the extent of disease with the patterns of biochemical changes is discussed with reference to several illustrative examples.