Leukocyte alkaline phosphatase and carcinoembryonic antigen in metastatic colorectal cancer patients.

Peripheral blood leukocyte alkaline phosphatase scores and plasma carcinoembryonic antigen levels in 26 patients with metastatic colorectal cancer were compared to those in 30 healthy controls. Patients had metastases to the liver and abdomen. The mean leukocyte alkaline phosphatase score in the metastatic colorectal cancer patients was significantly higher than in the control group (246 +/- 65 vs, 52 +/- 26, p less than 0.001); and the mean carcinoembryonic antigen level in the patients was also significantly higher than in the controls (110 +/- 100 vs, 4.9 +/- 3 ng/ml, p less than 0.001). One hundred percent of the metastatic cancer patients had elevated LAP scores and 73% of these patients had elevated CEA levels. There was a difference between the mean CEA levels in the patients with liver metastases and those with abdominal metastases (162 +/- 135 vs, 39 +/- 53 ng/ml, p less than 0.04). The results suggest that although both markers were elevated in metastatic colorectal cancer, the LAP score seems to be more useful in detecting metastatic disease, since we found 11% false negatives with the CEA level and 0% false negatives with the LAP score.