The serum enzyme pattern, consisting of GOT, GPT, lactate dehydrogenase, gamma glutamyl transpeptidase and alkaline phosphatase, was investigated in 128 patients with sonographically verified liver metastases. Gamma glutamyl transpeptidase and alkaline phosphatase turned out to be the most sensitive enzymes, being elevated in 89% and 88%, respectively. The GOT was elevated in 45% GPT in 37.5% and lactate dehydrogenase in 56% of all cases. The enzyme elevation did not correlate with the degree of liver involvement. In conclusion, pathological serum enzyme patterns are useful for the detection and follow up of liver metastases. Normal serum enzyme levels do not rule out the presence of liver metastases.