Radioimmunodetection of primary and metastatic germ cell tumors containing alpha-fetoprotein.

Radioimmunodetection with an 131I anti-alpha-fetoprotein (alpha FP) has been performed in 5 patients with germ cell tumors. In 3 of them, 5 of 6 recognized or suspected tumor sites could be demonstrated. In 1 of these patients, a clinically non-apparent primary tumor was detected by this method. The 2 other patients had received intensive chemotherapy and had a persistent elevation of serum alpha FP, although usual paraclinical examinations were normal. In these patients, the labelled antibody scan did not show any abnormality. These results suggest that radioimmunodetection can be useful in patients with nonseminomatous gonadal and extragonadal tumors at the time of presentation. Usefulness of radioimmunodetection in the follow-up of these patients remains to be determined. Even in our limited series, radioimmunodetection was of no help on localizing the sites of alpha FP secretion in treated patients in whom other methods had also failed to recognize the site of abnormal alpha FP synthesis.