Serum gastrin and human chorionic gonadotropin in the Zollinger-Ellison syndrome.

Prior to total gastrectomy, serum levels of gastrin and human chorionic gonadotropin (HCG) and its alpha- and beta-subunits (alpha-HCG and beta-HCG) were determined by radioimmunoassays in 40 patients with the Zollinger-Ellison syndrome. Basal serum gastrin levels greater than 1,500 pg/mL were found only in patients with metastases to lymph nodes or liver, while levels greater than 8,000 indicated massive liver replacement by tumor. Gastrin levels less than 1,500 pg/mL had no correlation with malignant behavior. Neither the calcium-infusion nor secretin-injection test was useful in identifying tumors as benign or malignant. Basal serum levels of alpha-HCG were elevated (> 7 ng/mL) in four of 20 patients with metastatic gastrinoma and were normal in all 16 patients with benign disease. There was a significant correlation between basal gastrin and alpha-HCG levels in patients with malignant gastrinoma but not for those with benign tumors. The results suggest that serum gastrin and alpha-HCG levels can be useful in assessing the biologic behavior of gastrinomas and in planning appropriate surgical and nonsurgical treatment.