Objective: [¹⁷⁷Lu]Lu-PSMA-617 is a radioisotope used in nuclear medicine. It is necessary to take appropriate measures to limit its exposure and ensures its airborne concentrations do not exceed legally permitted levels. Therefore, the purpose of this study was to measure the airborne radioactivity concentration in the inpatient room after administering [¹⁷⁷Lu]Lu-PSMA-617 to humans. Methods: Three males with advanced prostate-specific membrane antigen (PSMA)-positive metastatic castration resistant prostate cancer were intravenously administered [¹⁷⁷Lu]Lu-PSMA-617 (7.4 GBq ± 10%) in an inpatient room, and the airborne radioactivity concentrations were measured at two locations in the room (in the center of the room and at the bedside) using a filter collection method. Results: After administration of [¹⁷⁷Lu]Lu-PSMA-617, the airborne radioactivity concentrations measured were below the limit of detection (1.1 × 10⁻⁶ Bq/cm³ or 9.5 × 10⁻⁷ Bq/cm³) in all three humans, and all concentrations were consistently below the standard value of 1/10,000 of 2 × 10⁻² Bq/cm³, the legal airborne concentration limit of ¹⁷⁷Lu. Conclusion: The results of this study confirmed that the airborne concentration of [¹⁷⁷Lu]Lu-PSMA-617 after administration to humans was below the legally permitted level.

This survey was performed to investigate the incidence of adverse reactions to radiopharmaceuticals in FY2020 in Japan. The results are based on responses to questionnaires sent to nuclear medicine centers. Replies were obtained from 1,006 centers out of 1,212 to which the questionnaire was sent. A total of 940,758 administrations of radiopharmaceuticals were reported. There were 17 cases with adverse reactions, giving an incidence of adverse reactions of 1.8 per 100,000 cases. Two cases of defective products were reported, giving an incidence of defective products of 0.2 per 100,000 cases.