Whole‐body Autoradiography of Tumor‐bearing Hamsters with a New Tumor Imaging Agent, Indium‐111‐labeled Porphyrin

We have synthesized a new tumor imaging agent, 111In-labeled porphyrin (111In-ATN-2). In order to image transplantable pancreatic carcinoma in Syrian golden hamsters, we investigated the biodistribution of 111In-ATN-2 72 hr after injecting the agent by means of whole-body autoradiography. The efficacy of the agent was compared with that of 67Ga citrate. The images with 111In-ATN-2 were found to be clearer than those with 67Ga citrate. Tumor-to-tissue radiodistribution ratios of the former were higher than those of the latter. Thus, 111In-ATN-2 seems to be more useful for tumor diagnosis.