The role of radioimmunodetection in the management of testicular cancer.

Five patients with testicular cancer received an intravenous injection of between 1 and 2.5 mCi of iodine 131-labeled antibody to human chorionic gonadotropin (HCG) or alpha-fetoprotein (AFP), followed by total-body photoscanning to visualize areas of abnormal radioactivity. Blood-pool and nontarget sites of radioactivity were reduced by subtracting the images derived by injection of technetium Tc 99m-labeled components from the iodine 131 scans. The HCG-immune scintiscans proved helpful in tumor localization and in the selection of appropriate therapy, while the AFP scan presented corroborative evidence of widespread tumor. Elevated serum levels of these two markers did not hinder successful tumor detection and localization by this method of radioimmunodetection. Cancer radioimmunodetection with antibodies to HCG and to AFP appears to be a useful procedure for the pretreatment and posttreatment evaluation of patients with testicular cancer and can reveal sites of tumor not detected by other methods.