Occurrence of alpha-fetoprotein, Regan isoenzyme, and variant alkaline phosphatase in the serum of a patient with gastric cancer.

Regan isoenzyme, variant alkaline phosphatase, and alpha-fetoprotein were found in the serum of a patient with gastric cancer. The histology of the tumor was tubular adenocarcinoma. There were metastases in the retroperitoneal lymph nodes, but not in the liver. The liver was normal microscopically, with no evidence of bile duct obstruction. alpha-Fetoprotein in the tumor tissue was detected by immunoprecipitation reaction in agar. Regan isoenzyme and variant alkaline phosphatase were also detected in the tumor tissue and total alkaline phosphatase activity of the tissue was very high. These findings suggested their tumor origin.