背景:本研究旨在评估IIb级临床目标体积(CTV)优化对生存率的长期影响,口干症,鼻咽癌(NPC)患者的吞咽困难。
方法:回顾性分析2014年12月至2018年10月接受调强放疗的415例鼻咽癌患者的临床资料。将患者分为改良组和对照组。使用放射治疗肿瘤学小组/欧洲癌症研究和治疗组织评分评估晚期口干症和吞咽困难。使用Kaplan-Meier方法进行生存分析。比较两组之间晚期毒性和剂量参数的差异。使用回归分析评估生存和晚期毒性的预后因素。
结果:改良组患者出现晚期口干症和吞咽困难的频率低于对照组(P<0.001)。腮腺的平均剂量(Dmean)和V26;颌下腺的Dmean和V39;和舌下腺的Dmean,口腔,喉部,优越,中间,改良组咽下收缩肌均低于对照组(均P<0.001)。两组在总体上没有显著差异,局部无复发,无远处转移,或无进展生存期。腮腺和舌下腺的Dmean是口干症的危险因素。腮腺和舌下腺以及咽中缩窄肌的Dmean是吞咽困难的危险因素。
结论:对符合一定标准的鼻咽癌患者进行IIb级优化,特别是排除接受调强放疗的咽后淋巴结阳性,有可能更好地保护唾液和吞咽结构,减少晚期辐射诱导的口干症和吞咽困难的发展,同时保持长期生存。
BACKGROUND: This study aimed to assess the long-term effect of level IIb clinical target volume (CTV) optimisation on survival, xerostomia, and dysphagia in patients with nasopharyngeal carcinoma (NPC).
METHODS: Clinical data of 415 patients with NPC treated with intensity-modulated radiotherapy between December 2014 and October 2018 were retrospectively analysed. The patients were categorised into modified and comparison groups. Late xerostomia and dysphagia were evaluated using Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer scoring. Survival analysis was performed using the Kaplan-Meier method. Differences in late toxicity and dose parameters between both groups were compared. Prognostic factors for survival and late toxicity were assessed using regression analyses.
RESULTS: Patients in the modified group developed late xerostomia and dysphagia less frequently than those in the comparison group did (P < 0.001). The mean dose (Dmean) and V26 of parotid glands; Dmean and V39 of submandibular glands; and Dmean of sublingual glands, oral cavity, larynx, and superior, middle, and lower pharyngeal constrictor muscles were lower in the modified group than those in the comparison group (all P < 0.001). Both groups had no significant differences in overall, local recurrence-free, distant metastasis-free, or progression-free survival. The Dmean of the parotid and sublingual glands was a risk factor for xerostomia. The Dmean of the parotid and sublingual glands and middle pharyngeal constrictor muscle was a risk factor for dysphagia.
CONCLUSIONS: Level IIb optimisation in NPC patients who meet certain criteria specially the exclusion of positive retropharyngeal nodes treated with intensity-modulated radiotherapy has the potential to better protect the salivary and swallowing structures, decreasing the development of late radiation-induced xerostomia and dysphagia while maintaining long-term survival.