Radioimmunodetection of prostatic cancer. In vivo use of radioactive antibodies against prostatic acid phosphatase for diagnosis and detection of prostatic cancer by nuclear imaging.

Radioimmunodetection (RAID) of prostatic cancer is done by injecting 131I-labeled rabbit antibody IgG against prostatic acid phosphatase (PAP) and performing total-body photoscans with a gamma scintillation camera. Of two patients tested, the PAP RAID scintiscans located the primary or recurrent prostatic cancers in both and showed no disease in the lungs of the patient shown subsequently to have lung cancer. The lung tumor nodules showing anti-PAP IgG accretion were assumed to be of prostatic cancer origin, since one of the original tumors removed from this patient's other lung a year earlier stained for PAP by immunohistochemistry. This study showed that PAP RAID can locate primary and metastatic tumors of prostatic origin.