CA72-4 compared with carcinoembryonic antigen as a tumour marker for gastric cancer.

Serum levels of a newly identified, tumour-associated antigen, CA72-4, were measured in 86 patients with histologically proven gastric carcinoma. Preoperative levels of CA72-4 in serum tended to be higher with increased dissemination of the cancer. Elevated levels of CA72-4 (above 5.0 U/ml) were significantly more frequent than those of carcinoembryonic antigen (CEA) (above 5.6 ng/ml) in patients with stage III or IV (P less than 0.01) carcinoma, in patients with Borrmann type 4 (P less than 0.01), and in patients with peritoneal metastasis (P less than 0.01). No correlation was seen between serum levels of CA72-4 and those of CEA. Serum levels of CA72-4 were lower 1 month after gastrectomy in 25 of 39 patients with resected cancers. In each of 4 patients with recurrence, lower levels of CA72-4 after gastrectomy were replaced by elevated levels on detection of the recurrence of cancer. These results indicate that CA72-4 is highly specific to gastric cancer and may be more reliable as a tumour marker than CEA for gastric cancer.