Radiation precaution guidance for patients receiving lutetium-177 (Lu-177) prostate-specific membrane antigen (PSMA) therapy varies widely across centers worldwide, according to a study published November 5 in the Journal of Nuclear Medicine. 

The finding is from an international survey of centers performing Lu-177 PSMA radiopharmaceutical therapy (RPT), and suggests that guidance on distancing, transportation, household hygiene, and social interactions after treatment requires standardization, noted an international group of experts. 

"Patients and their families require clear and reliable information about preparation, therapy procedures, and discharge precautions to minimize radiation exposure, improve patient compliance, and support safe, standardized therapy protocols," the researchers wrote. 

Because prostate cancer patients remain radioactive after Lu-177 PSMA RPT, clear discharge guidance is essential to protect family members, particularly children and pregnant women, from unnecessary radiation exposure, the authors wrote. Despite this need, no harmonized guidance exists on what patients, families, and caregivers should be told before, during, and after therapy, they added. 

To address this gap, the researchers distributed a 152-question web-based survey in January 2025 to 186 centers known to perform Lu-177 PSMA RPT, closing in October 2025. The survey covered four domains: pretreatment procedures, therapy procedures, radiation precautions guidance, and posttreatment procedures, with separate branches for inpatient and outpatient settings. 

A total of 102 centers from 23 countries across five continents participated. Sixty-five percent performed Lu-177 PSMA RPT as an outpatient procedure and 35% as inpatient. According to the responses, there is broad consensus on pretreatment and posttreatment practices. Nearly all centers impose no fasting requirements, allow continuation of regular medications, provide written discharge instructions, and place no restrictions on diet, alcohol, or physical activity. 

In contrast, there is substantial variability in posttreatment radiation precautions, particularly regarding distancing measures, duration of precautions, transportation after discharge, household and hygiene recommendations, and guidance affecting social interactions. Among outpatient centers, for instance, the recommended duration for maintaining distance from others after treatment ranged from one to three days at some sites and up to seven days at others, while 20% issued no formal distance guidance at all. Further, recommended separation distances ranged from one meter to three meters. Guidance on transportation, household items, hygiene, incontinence material handling, and sexual activity also diverged considerably. 

"This international survey demonstrated broad consensus for core clinical procedures but showed variability in posttreatment radiation precautions after RPT," the researchers wrote. 

Based on its findings, the team developed a structured patient information template organized around the four survey domains. The template is intended to complement, not replace existing national regulations and institutional protocols, they noted. 

"By systematically capturing current practice and expert opinion, this project provides a structured overview of common ground and differences and translates them into a pragmatic patient information template," the group wrote. 

Future work should aim to validate the patient information template in clinical practice, including assessment of patient comprehension, satisfaction, and adherence to recommended measures, the authors concluded. 

The full article is available here.