Lutetium-177 Therapy in Italy: Environmental Impact Assessment in Anticipation of Its Widespread Use in Prostate Cancer Treatment.

Abstract: This article addresses the evolving state of lutetium-177 radiopharmaceutical therapies in Italy, focusing on the importance of the definition of patient management practices regarding the approved treatments based on [177Lu]Lu-DOTATATE for neuroendocrine tumors and [177Lu]Lu-PSMA-617 for metastatic castration-resistant prostate cancer. Italian medical facilities are facing new challenges with the increase in the demand for such therapies while transitioning from restrictive hospitalization requirements to more flexible outpatient options. Therefore, four management strategies are described here, varying from immediate discharge after the administration to 24-h hospitalization, and their environmental and radiation safety implications are evaluated through simple models aimed at assessing the effective doses on the local population and wastewater purification plant workers. Results show that, while higher effective doses may be caused by an immediate discharge-based modality, they remain within acceptable limits, particularly when dealing with a smaller number of patients. Prolonged hospitalizations guarantee superior radiation safety levels but might not be sustainable with the expected increase in patient volumes in the future.