Wirral Breast Unit, Wirral University Teaching Hospital, Clatterbridge Hospital, Wirral, Merseyside, CH63 4JY, UK.
World J Surg. 2019 Sep;43(9):2250-2253. doi: 10.1007/s00268-019-05024-9.
Sentinel node biopsy (SNB) is the standard of care for nodal staging in breast cancer. Currently, radioisotope-guided SNB is the standard technique. We have undertaken this study to analyse radiation exposure during SNB for breast cancer over a significant period of time.
The study was conducted over a period of 41 months and included 183 patients. The radioisotope was usually administered the day preceding the surgery at a dose of 40 MBq (±10%), and a lower dose of 20 MBq (±10%) was given if injected on the day of surgery. The radiation exposure was measured by dosimeters worn by the surgeon and surgical assistant.
The surgical procedures performed were mastectomy and SNB (56 patients), wide local excision and SNB (109 patients), and SNB alone (18 patients). The median time interval between the injection and surgery was 19.3 h, and median duration of surgery 93 min. The annual exposure for the surgeon was 0.125 mSv (range 0.01-0.03 mSv) and for the assistant was 0.265 (range 0.01-0.13 mSv).
Contrary to other studies, we found the radiation exposure in the assistant was higher than that in the surgeon and we think this is because the assistant is positioned closer to the injection site during the procedure. However, the cumulative levels of radiation with SNB were very low and significantly below the permissible limits. The timing of injection, type of breast surgery and duration of procedure did not affect the levels of radiation exposure.
前哨淋巴结活检（SNB）是乳腺癌淋巴结分期的标准治疗方法。目前，放射性同位素引导的 SNB 是标准技术。我们进行这项研究是为了在很长一段时间内分析 SNB 过程中乳腺癌的辐射暴露。
这项研究在 41 个月的时间内进行，共纳入 183 名患者。放射性同位素通常在手术前一天以 40MBq（±10%）的剂量给药，如果在手术当天给药，则给予 20MBq（±10%）的较低剂量。手术医生和手术助手佩戴剂量计来测量辐射暴露。
进行的手术程序包括乳房切除术和 SNB（56 例）、广泛局部切除术和 SNB（109 例）以及单独 SNB（18 例）。注射和手术之间的中位时间间隔为 19.3 小时，中位手术时间为 93 分钟。医生的年辐射暴露量为 0.125mSv（范围 0.01-0.03mSv），助手为 0.265mSv（范围 0.01-0.13mSv）。
与其他研究不同，我们发现助手的辐射暴露高于医生，我们认为这是因为助手在手术过程中更接近注射部位。然而，SNB 的累积辐射水平非常低，明显低于允许的限度。注射时间、乳房手术类型和手术持续时间均不会影响辐射暴露水平。
