Department of Radiation Oncology, The Ohio State University Comprehensive Cancer Center, Arthur G. James Cancer Hospital and Solove Research Institute, Stefanie Spielman Comprehensive Breast Center, Columbus, USA.
Department of Biomedical Informatics, The Ohio State University, Columbus, USA.
Radiother Oncol. 2021 Feb;155:167-173. doi: 10.1016/j.radonc.2020.10.042. Epub 2020 Nov 4.
BACKGROUND/PURPOSE: Rates of acute esophagitis in breast cancer patients undergoing regional nodal irradiation (RNI) are under-reported. We set to identify esophageal dose-volume constraints associated with grade 2 esophagitis (G2E). We hypothesized that the G2E rate was higher with intensity modulated radiation therapy (IMRT) vs. 3D conformal radiation therapy (3DCRT).
MATERIALS/METHODS: We identified patients that received RNI (50 Gy/25 fractions) from 1/2013 to 6/2019. We retrospectively contoured the esophagus in a consistent manner and recorded esophageal mean dose, max dose, and V10-V50. Our primary endpoint was the G2E rate. Receiver operating characteristics curves analysis (e.g., Youden's J statistic) were used to determine the cutpoints for the dosimetric parameters which were then tested in logistic regression models.
We identified 531 patients (50% left-sided; 41% IMRT; 16.2% G2E). G2E was significantly higher in IMRT vs. 3DCRT patients (23.6% vs. 10.9%, p < 0.0001). All esophageal dosimetric parameters were significantly associated with G2E after adjusting for age and laterality. The cutpoints for esophageal mean dose, V10 and V20 were 11 Gy, 30%, and 15%, respectively. The associations between the dichotomized dose-volume parameters and G2E were OR = 3.82 (95% CI 2.28-6.40, p < 0.0001) for esophageal mean dose, OR = 5.37 (95% CI 3.01-9.58, p < 0.0001) for esophageal V10, and OR = 3.23 (95% CI 1.93-5.41, p < 0.0001) for esophageal V20.
In patients receiving RNI with modern techniques, we found that G2E occurs in >15%, and more frequently with IMRT. These data strongly support the routine contouring of the esophagus in RNI planning, and our constraints should be incorporated in future prospective protocols of RNI.
背景/目的：接受区域淋巴结照射（RNI）的乳腺癌患者发生急性食管炎的比率报告不足。我们旨在确定与 2 级食管炎（G2E）相关的食管剂量-体积限制。我们假设与三维适形放疗（3DCRT）相比，调强放疗（IMRT）的 G2E 发生率更高。
材料/方法：我们从 2013 年 1 月至 2019 年 6 月确定了接受 RNI（50 Gy/25 次）的患者。我们以一致的方式回顾性地勾画食管，并记录食管平均剂量、最大剂量和 V10-V50。我们的主要终点是 G2E 发生率。使用受试者工作特征曲线分析（例如，约登 J 统计量）来确定剂量学参数的截止值，然后在逻辑回归模型中进行测试。
我们确定了 531 名患者（50%为左侧；41%为 IMRT；16.2%为 G2E）。与 3DCRT 患者相比，IMRT 患者的 G2E 发生率明显更高（23.6%比 10.9%，p<0.0001）。调整年龄和侧别后，所有食管剂量学参数均与 G2E 显著相关。食管平均剂量、V10 和 V20 的截断值分别为 11 Gy、30%和 15%。将剂量-体积参数二分类后，与 G2E 的相关性为食管平均剂量的 OR=3.82（95%CI 2.28-6.40，p<0.0001），食管 V10 的 OR=5.37（95%CI 3.01-9.58，p<0.0001），食管 V20 的 OR=3.23（95%CI 1.93-5.41，p<0.0001）。
在接受现代技术 RNI 的患者中，我们发现 G2E 发生率超过 15%，且 IMRT 更为常见。这些数据强烈支持在 RNI 计划中常规勾画食管，我们的限制应纳入未来 RNI 的前瞻性协议中。
