Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Radiation Oncology, Peking University Cancer Hospital and Institute, Beijing, P.R. China.
Pract Radiat Oncol. 2022 Mar-Apr;12(2):125-134. doi: 10.1016/j.prro.2021.10.003. Epub 2021 Oct 17.
To investigate the impact of excluding irradiation of inguinal lymph nodes (ILNs) and external iliac lymph nodes (ELNs) during neoadjuvant (chemo)radiotherapy in a locally advanced lower rectal cancer (LALRC) with anal sphincter invasion.
A total of 214 LALRC patients with anal sphincter invasion according to pre-treatment magnetic resonance imaging who underwent neoadjuvant (chemo)radiotherapy followed by surgery between September 2010 and May 2019 were enrolled. ILNs and ELNs were clinically negative pre-treatment and were excluded from irradiation. Failure rates and patterns of ILNs and ELNs and survival were analyzed. Nomograms for predicting ILN and ELN failure risk were also constructed.
The median follow-up was 53.3 months. The 3-year failure rates were 3.7% for ILNs and 3.3% for ELNs. Only 1 patient developed isolated ILN failure, and no patient experienced isolated ELN failure. Multivariate analyses demonstrated that lower edge of tumors invaded or located below the dentate line (odds ratio [OR], 7.513; P = .013), high histological grade (OR, 6.892; P = .017), and perineural invasion (OR, 7.111; P = .023) were significantly related to ILN failure. Both perineural invasion (OR, 8.923; P = .011) and high histological grade (OR, 8.129; P = .011) showed a strong correlation with ELN failure. The concordance index of nomograms for predicting ILN and ELN failure risk were 0.842 and 0.880, respectively. The 3-year local recurrence free survival, disease-free survival, and overall survival were 94.6% (95% confidence interval [CI], 91.3%-97.9%), 77.7% (95% CI, 71.8%-83.6%), and 91.9% (95% CI, 87.8%-96.0%), respectively, for the whole cohort.
Excluding ILNs and ELNs from irradiation was associated with an acceptably low failure risk for LALRC invading the anal sphincter. These findings help to refine existing guidelines for clinical target volume delineation of ILNs and ELNs during neoadjuvant (chemo)radiotherapy in rectal cancer.
探讨在局部晚期低位直肠癌（LALRC）伴有肛门括约肌侵犯的新辅助（放化疗）中，排除腹股沟淋巴结（ILNs）和外髂淋巴结（ELNs）照射的影响。
共纳入 214 例术前磁共振成像提示有肛门括约肌侵犯且接受新辅助（放化疗）联合手术治疗的 LALRC 患者，新辅助（放化疗）治疗于 2010 年 9 月至 2019 年 5 月进行。ILNs 和 ELNs 在治疗前临床检查均为阴性，未进行照射。分析 ILNs 和 ELNs 的失败率和模式以及生存情况。还构建了预测 ILN 和 ELN 失败风险的列线图。
中位随访时间为 53.3 个月。ILNs 的 3 年失败率为 3.7%，ELNs 的失败率为 3.3%。仅 1 例患者出现孤立性 ILN 失败，无患者出现孤立性 ELN 失败。多因素分析显示，肿瘤下缘侵犯或位于齿状线以下（比值比[OR]，7.513；P =.013）、高组织学分级（OR，6.892；P =.017）和神经周围侵犯（OR，7.111；P =.023）与 ILN 失败显著相关。神经周围侵犯（OR，8.923；P =.011）和高组织学分级（OR，8.129；P =.011）均与 ELN 失败密切相关。预测 ILN 和 ELN 失败风险的列线图的一致性指数分别为 0.842 和 0.880。全队列的 3 年局部无复发生存率、无病生存率和总生存率分别为 94.6%（95%可信区间[CI]，91.3%-97.9%）、77.7%（95% CI，71.8%-83.6%）和 91.9%（95% CI，87.8%-96.0%）。
在局部晚期低位直肠癌伴有肛门括约肌侵犯的新辅助（放化疗）中，排除 ILNs 和 ELNs 的照射与较低的失败风险相关。这些发现有助于为直肠癌新辅助（放化疗）中 ILNs 和 ELNs 的临床靶区勾画提供参考。
