Department of Radiation Oncology, UCI Chao Family Comprehensive Cancer Center, Orange, California; Department of Radiation Oncology, Ohio State University Comprehensive Cancer Center, Columbus, Ohio.
Department of Radiation Oncology, Ohio State University Comprehensive Cancer Center, Columbus, Ohio.
Int J Radiat Oncol Biol Phys. 2023 Oct 1;117(2):452-460. doi: 10.1016/j.ijrobp.2023.04.003. Epub 2023 Apr 13.
Breast cancer-related lymphedema (BCRL) is a treatment complication that significantly reduces patient quality of life. Regional nodal irradiation (RNI) may increase the risk of BCRL. Recently, a region of the axilla known as the axillary-lateral thoracic vessel juncture (ALTJ) was identified as a potential organ at risk (OAR). Here, we set out to validate whether radiation dose to the ALTJ is associated with BCRL.
We identified patients with stage II-III breast cancer treated with adjuvant RNI from 2013 to 2018, excluding those with BCRL preradiation. We defined BCRL as difference in arm circumference between the ipsilateral and contralateral limb >2.5 cm at any 1 encounter or ≥2 cm on ≥2 visits. All patients suspected of having BCRL at routine follow-up visits were referred to physical therapy for confirmation. The ALTJ was retrospectively contoured and dose metrics were collected. Cox proportional hazards regression models were used to test the association between clinical and dosimetric parameters with the development of BCRL.
The study population included 378 patients with a median age of 53 years, median body mass index of 28.4 kg/m, and median of 18 axillary nodes removed; 71% underwent mastectomy. Median follow-up was 70 months (interquartile range, 55-89.7 months). BCRL developed in 101 patients at a median of 18.9 months (interquartile range, 9.9-32.4 months), with a corresponding 5-year cumulative incidence BCRL of 25.8%. On multivariate analysis, none of the ALTJ metrics were associated with BCRL risk. Only increasing age, increasing body mass index, and increasing number of nodes were associated with a higher risk of developing BCRL. The 6-year locoregional recurrence rate was 3.2%, the axillary recurrence rate was 1.7%, and the isolated axillary recurrence rate was 0%.
The ALTJ is not validated as a critical OAR for reducing BCRL risk. Until such an OAR is discovered, the axillary PTV should not be modified or dose reduced in efforts to reduce BCRL.
乳腺癌相关淋巴水肿（BCRL）是一种治疗并发症，显著降低了患者的生活质量。区域淋巴结照射（RNI）可能会增加 BCRL 的风险。最近，腋窝中一个被称为腋窝-侧胸血管交界处（ALTJ）的区域被确定为潜在的危及器官（OAR）。在这里，我们旨在验证 ALTJ 的照射剂量是否与 BCRL 相关。
我们从 2013 年至 2018 年确定了接受辅助 RNI 治疗的 II-III 期乳腺癌患者，排除了放射前有 BCRL 的患者。我们将 BCRL 定义为同侧和对侧肢体之间的臂围差异> 2.5 厘米，或在≥2 次就诊时≥2 厘米。所有在常规随访就诊时怀疑患有 BCRL 的患者均被转诊至物理治疗以进行确认。回顾性地勾画 ALTJ 并收集剂量指标。使用 Cox 比例风险回归模型测试临床和剂量学参数与 BCRL 发展之间的关联。
研究人群包括 378 名中位年龄为 53 岁、中位体重指数为 28.4kg/m 和中位切除 18 个腋窝淋巴结的患者；71%接受了乳房切除术。中位随访时间为 70 个月（四分位距，55-89.7 个月）。101 名患者在中位时间 18.9 个月（四分位距，9.9-32.4 个月）时发生了 BCRL，相应的 5 年累积 BCRL 发生率为 25.8%。多变量分析显示，ALTJ 指标均与 BCRL 风险无关。只有年龄增加、体重指数增加和淋巴结数量增加与 BCRL 发病风险增加相关。6 年局部区域复发率为 3.2%，腋窝复发率为 1.7%，孤立性腋窝复发率为 0%。
ALTJ 尚未被验证为降低 BCRL 风险的关键 OAR。在发现这样的 OAR 之前，为了降低 BCRL 的风险，不应对腋窝 PTV 进行修改或降低剂量。
