Emergency Appendectomy during the Early Phase after ¹⁷⁷Lu-DOTATATE Therapy: A Case Report with Perioperative...

Peptide receptor radionuclide therapy (PRRT) with ¹⁷⁷Lu-DOTATATE has become an established treatment for somatostatin receptor-positive neuroendocrine tumors. However, the safety of performing emergency surgery during the early post-treatment period remains unclear, given concerns regarding radiation exposure and potential contamination. We report a case of acute appendicitis requiring emergency surgery shortly after PRRT, with a focus on perioperative radiation safety.

A 75-year-old man with a pancreatic neuroendocrine tumor and multiple liver metastases underwent PRRT at another institution. Six days after treatment, he developed acute appendicitis and was referred to our hospital. Laboratory findings showed leukocytosis and elevated inflammatory markers. Emergency laparoscopic appendectomy was performed, and intraoperative radiation dose rates were measured using a survey meter. At a distance of 1 m from the patient, radiation levels were low (1.1 μSv/h), while measurements at 20 cm from the operative field ranged from 8.4 to 12.2 μSv/h, remaining within acceptable safety limits. Radiation levels detected in urine were also low (0.2 μSv/h at 5 cm). The postoperative course was uneventful, and the patient was discharged on POD 4 without complications.

This case demonstrates that emergency surgery can be performed safely during the early phase after PRRT when appropriate radiation safety precautions are implemented. Radiation exposure to surgical staff remained minimal at typical working distances, and even near-field exposure was within acceptable limits. Urgent surgical intervention should not be unnecessarily delayed following PRRT when clinically indicated, provided that appropriate monitoring and precautions are in place.