Serum levels of carcinoembryonic antigen, gastrointestinal cancer-associated antigen and alphafetoprotein in staging and management of patients with advanced carcinoma of the stomach

Serum levels of carcinoembryonic antigen (CEA), gastrointestinal cancer-associated antigen (GICA or CA 19-9), and alphafetoprotein (AFP) were concurrently determined in patients with carcinoma of the stomach: in 84 preoperatively, and in 67 serially postoperatively. Before surgery, serum CEA gave information about the tumor load analogous to serum GICA in 69% of the patients: true-positive in 25% and false-negative in 43%; less information in 18% and more in 14%. The sensitivity of the test tended to be better in the more advanced stages, and was higher for CEA with GICA than for CEA alone or GICA alone. During follow-up, serum CEA gave information about the presence or absence of active disease analogous to serum GICA in 78% of the patients: true-positive in 30%, true-negative in 36% and false-negative in 12%; less information in 9% and more in 13%. Neither test gave any false-positive indications. Sensitivity of the test rose from 67% for CEA alone and 60% for GICA alone to 81% for CEA with GICA. Serum AFP was elevated only preoperatively in 2% of patients. We conclude that joint application of CEA and GICA tests gave only slightly better preoperative sensitivity than CEA alone or GICA alone but proved fairly sensitive for postoperative follow-up of the patients. AFP was of little value for either purpose.