Occupational Radiation Exposure During SLNB in Endometrial Cancer

Objectives: Occupational radiation exposure during procedures involving unsealed radioactive sources represents a potential concern for medical personnel. This prospective observational study aimed to evaluate whole-body and extremity radiation doses received by surgical staff during radio-guided sentinel lymph node biopsy (SLNB) in patients with endometrial cancer (EC). Material and Methods: A prospective assessment of occupational radiation exposure was conducted during radio-guided SLNB procedures performed between January 2022 and August 2023. Each patient received a cervical injection of 4 mCi of 99mTc-labelled albumin nanocolloid on the day of surgery. Radiation doses to the primary surgeon and assistant were measured using thermoluminescent dosimeters (TLDs) worn as whole-body badges (Hp (10)) and extremity monitors (Hp(0.07)). Dosimetric data were analysed descriptively at the monitoring-period level, and exploratory paired comparisons were performed. Results: Radiation measurements were obtained from 29 SLNB procedures. The mean time interval between tracer application and surgery was 244.82 ± 26.74 minutes (range: 210-290 minutes), while the mean duration of surgery was 128.27 ± 20.79 minutes (range: 90-165 minutes). The average annual whole-body and extremity doses were 284 µSv and 250 µSv for the surgeon, and 314 µSv and 270 µSv for the surgeon assistant, respectively. The mean whole-body dose per intervention was 19.6 µSv for the assistant compared with 17.7 µSv for the primary surgeon. Period-level analysis demonstrated consistent proportional differences between operators without statistical significance. All recorded doses remained substantially below established occupational limits. Conclusion: Occupational radiation exposure during radio-guided SLNB in EC was low for both operators under routine clinical conditions and remained well within regulatory thresholds. Extrapolation based on the observed mean dose per procedure indicates that approximately 800 interventions annually could be performed without exceeding occupational dose limits. Findings should be interpreted within the context of a single-centre observational design.