From the Division of Plastic and Reconstructive Surgery.
Department of Radiation Oncology, University of California, San Francisco.
Plast Reconstr Surg. 2024 May 1;153(5):1000-1009. doi: 10.1097/PRS.0000000000010824. Epub 2023 Jun 19.
Intensity-modulated radiation therapy and other modifiable radiation factors have been associated with decreased radiation toxicity. These factors could allow for improved reconstructive outcomes in patients requiring postmastectomy radiation therapy (PMRT). However, they have not yet been well studied in implant-based breast reconstruction.
The authors performed a retrospective chart review of patients who underwent mastectomy with immediate tissue expander placement followed by PMRT. Radiation characteristics were collected, including radiation technique, bolus regimen, x-ray energy, fractionation, maximum radiation hot spot, and tissue volume receiving more than 105% or more than 107% of the prescription dose. Reconstructive complications occurring after initiation of PMRT were analyzed with respect to these radiation characteristics.
Sixty-eight patients (70 breasts) were included in this study. The overall complication rate was 28.6%, with infection being the most common complication (24.3%), requiring removal of the tissue expander or implant in greater than half of infections (15.7%). Maximum radiation hot spot was greater in patients who required explantation after PMRT, and this approached statistical significance (114.5% ± 7.2% versus 111.4% ± 4.4%; P = 0.059). Tissue volume receiving more than 105% and 107% were also greater in patients who required explantation after PMRT (42.1% ± 17.1% versus 33.0% ± 20.9% and 16.4% ± 14.5% versus 11.3% ± 14.6%, respectively); however, this was not statistically significant ( P = 0.176 and P = 0.313, respectively). There were no significant differences in complication rates between patients with respect to radiation technique or other radiation characteristics studied.
Minimizing the radiation hot spots and volumes of tissue receiving greater than the prescription dose of radiation may improve reconstructive outcomes in patients undergoing implant-based breast reconstruction followed by PMRT.
CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.
调强放疗和其他可调节的放疗因素与降低放疗毒性有关。这些因素可能使接受乳房切除术后放疗（PMRT）的患者获得更好的重建效果。然而，它们在基于植入物的乳房重建中尚未得到很好的研究。
作者对接受乳房切除术和即刻组织扩张器放置后行 PMRT 的患者进行了回顾性图表审查。收集了放疗特征，包括放疗技术、敷贴剂方案、X 射线能量、分次剂量、最大放疗热点以及接受处方剂量 105%以上或 107%以上的组织体积。分析了 PMRT 开始后出现的重建并发症与这些放疗特征的关系。
本研究共纳入 68 例（70 侧乳房）患者。总体并发症发生率为 28.6%，其中感染最为常见（24.3%），超过一半的感染（15.7%）需要取出组织扩张器或植入物。PMRT 后需要取出的患者最大放疗热点更高，接近统计学意义（114.5%±7.2%比 111.4%±4.4%；P=0.059）。PMRT 后需要取出的患者接受 105%和 107%以上剂量照射的组织体积也更大（42.1%±17.1%比 33.0%±20.9%和 16.4%±14.5%比 11.3%±14.6%；P=0.176 和 P=0.313），但无统计学意义。在放疗技术或其他研究的放疗特征方面，患者的并发症发生率没有显著差异。
在接受基于植入物的乳房重建并随后行 PMRT 的患者中，尽量减少放疗热点和接受超过处方剂量的组织体积可能会改善重建效果。
临床问题/证据水平：治疗性，III 级。
