Department of Radiation Oncology, Sun Yat-sen University Cancer Center; State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangzhou, Guangdong, 510060, P. R. China.
Perception vision medical technology co. LTD, Guangzhou, Guangdong, 510275, P. R. China.
Cancer Commun (Lond). 2021 Apr;41(4):303-315. doi: 10.1002/cac2.12145. Epub 2021 Feb 26.
Oral cavity (OC), oropharyngeal (OP), hypopharyngeal (HP), and laryngeal (LA) squamous cell carcinoma (SCC) have a high incidence of regional lymph node metastasis (LNM). Elective irradiation for clinically node-negative neck is routinely administered to treat lymph nodes harboring occult metastasis. However, the optimal elective irradiation schemes are still inconclusive. In this study, we aimed to establish individualized elective irradiation schemes for the ipsilateral and contralateral node-negative neck of these four types of cancer.
From July 2005 to December 2018, 793 patients with OC-SCC, 464 with OP-SCC, 413 with HP-SCC, and 645 with LA-SCC were recruited retrospectively. Based on the actual incidence of LNM and the tumor characteristics, risk factors for contralateral LNM, as well as node level coverage schemes for elective irradiation, were determined using logistic regression analysis. Additionally, we developed a publicly available online tool to facilitate the widespread clinical use of these schemes.
For the ipsilateral node-negative neck, elective irradiation at levels I-III for OC-SCC and levels II-IVa for OP-, HP- and LA-SCC are generally recommended. In addition, level VIIa should be included in patients with OP-SCC. Multivariate analyses revealed that posterior hypopharyngeal wall and post-cricoid region involvement were independently associated with level VIIa metastasis in HP-SCC (all P < 0.05). For the contralateral node-negative neck, multivariate analyses revealed that ipsilateral N2b2-N3, tumors with body midline involvement, and degree of tumor invasion were the independent factors for contralateral LNM (all P < 0.05). In patients who require contralateral neck irradiation, levels I-II are recommended for OC-SCC, and additional level III is recommended for patients with ipsilateral N3 disease. Levels II-III are recommended for OP-, HP-, and LA-SCC, and additional level IVa is recommended for patients with advanced T or ipsilateral N classifications. Furthermore, additional level VIIa is recommended only for OP-SCC with T4 and ipsilateral N3 disease.
Based on our findings, we suggest that individualized and computer-aided elective irradiation schemes could reduce irradiation volumes in OC-, OP- and HP-SCC patients, as compared to current guidelines, and could thus positively impact the patients' quality of life after radiotherapy.
口腔（OC）、口咽（OP）、下咽（HP）和喉（LA）鳞状细胞癌（SCC）的区域淋巴结转移（LNM）发生率较高。对于临床淋巴结阴性的颈部，常规行选择性照射以治疗隐匿性转移的淋巴结。然而，最佳的选择性照射方案仍不明确。本研究旨在为这四种癌症的同侧和对侧淋巴结阴性颈部建立个体化的选择性照射方案。
回顾性纳入 2005 年 7 月至 2018 年 12 月 793 例 OC-SCC、464 例 OP-SCC、413 例 HP-SCC 和 645 例 LA-SCC 患者。基于实际的 LNM 发生率和肿瘤特征、对侧 LNM 的危险因素以及选择性照射的淋巴结水平覆盖方案，采用 logistic 回归分析进行确定。此外，我们开发了一个可供广泛使用的在线工具，以促进这些方案的临床应用。
对于同侧淋巴结阴性颈部，OC-SCC 推荐照射 I-III 水平，OP-、HP-和 LA-SCC 推荐照射 II-IVa 水平。此外，OP-SCC 患者应包括 VIIa 水平。多变量分析显示，后咽壁和环后区受累是 HP-SCC 中 VIIa 转移的独立危险因素（均 P < 0.05）。对于对侧淋巴结阴性颈部，多变量分析显示同侧 N2b2-N3、中线受累的肿瘤和肿瘤侵犯程度是对侧 LNM 的独立因素（均 P < 0.05）。对于需要对侧颈部照射的患者，OC-SCC 推荐照射 I-II 水平，对于同侧 N3 疾病的患者，推荐额外照射 III 水平。OP-、HP-和 LA-SCC 推荐照射 II-III 水平，对于 T 分期或同侧 N 分类较晚的患者，推荐额外照射 IVa 水平。此外，仅对于 T4 和同侧 N3 疾病的 OP-SCC 患者推荐额外照射 VIIa 水平。
根据我们的研究结果，我们建议与目前的指南相比，基于个人情况和计算机辅助的选择性照射方案可减少 OC-、OP-和 HP-SCC 患者的照射体积，从而积极影响放疗后患者的生活质量。
