鼻咽癌内侧组咽后淋巴结不进行预防照射的可行性分析

Feasibility analysis of non-prophylactic irradiation of retropharyngeal lymph nodes in medial group of nasopharyngeal carcinoma

目的分析鼻咽癌内侧组咽后淋巴结不进行预防照射的可行性。方法选取183例初诊无转移并且接受内侧组咽后淋巴结区域不预防照射的鼻咽癌患者作为观察组,再根据性别、T分期、N分期及M分期进行1∶1配对选取183例接受过内侧组咽后淋巴结常规照射的鼻咽癌患者作为对照组。两组患者均接受根治性调强放疗。主要观察指标包括无局部复发生存率(LRFS)、无区域复发生存率(RRFS)、无远处转移生存率(DMFS)和总生存率;次要观察指标包括口腔和喉的平均照射剂量、急性黏膜炎、晚期放射损伤(口干、吞咽困难)。结果两组患者均183例,观察组180例接受化疗,对照组169例接受化疗。观察组随访10~109个月,中位随访69个月,5年内病死26例,9例出现局部复发,3例出现区域复发,21例出现远处转移,5年LRFS、RRFS、DMFS和总生存率分别为94.8%、98.3%、88.5%、85.5%;对照组随访5~121个月,中位随访67个月,5年内病死28例,10例出现局部复发,5例出现区域复发,24例出现远处转移,5年LRFS、RRFS、DMFS和总生存率分别为94.2%、97.1%、86.7%、84.7%;两组患者LRFS、RRFS、DMFS和总生存率比较,差异均无统计学意义(P﹥0.05)。观察组患者口腔平均照射剂量明显低于对照组(P﹤0.01),喉最小、平均、最大照射剂量均明显低于对照组(P﹤0.01)。两组患者均按计划完成放疗,均无Ⅳ级黏膜反应发生,观察组主要出现Ⅰ、Ⅱ级急性口腔黏膜反应,Ⅲ级急性口腔黏膜反应发生率明显低于对照组(P﹤0.01)。两组患者0~1级、2级口干、吞咽困难发生率均无明显差异(P﹥0.05)。结论鼻咽癌内侧组咽后淋巴结不预防照射明显降低了口腔和喉的平均照射剂量,从而降低3级急性黏膜炎的发生风险,有利于保护吞咽相关结构,并且不影响疾病控制和生存。

Objective To analyze the feasibility of non-prophylactic irradiation of retropharyngeal lymph nodes in the medial group of nasopharyngeal carcinoma.Method A total of 183 patients with nasopharyngeal carcinoma who were initially diagnosed without metastasis and who received no prophylactic irradiation of the retropharyngeal lymph node region of the medial group were selected as the observation group.Then according to gender,T stage,N stage and M stage,183 patients with nasopharyngeal carcinoma who had received conventional irradiation of retropharyngeal lymph nodes in the medial group were selected as the control group.Main outcome measures included local relapse freesurvival(LRFS),regional recurrence-free survival(RRFS),distant metastasis-free survival(DMFS),and overall survival.Secondary outcomes included mean dose to the mouth and larynx,acute mucositis,and late radiation injury(dry mouth,dysphagia).Result There were 183 patients in both groups,180 patients in the observation group received chemotherapy,and 169 patients in the control group received chemotherapy.The observation group was followed up for 10-109 months,with a median follow-up of 69 months.Within 5 years,26 cases died,9 cases had local recurrence,3 cases had regional recurrence,and 21 cases had distant metastasis,the 5-year LRFS,RRFS,DMFS and overall survival rates were 94.8%,98.3%,88.5%,and 85.5%,respectively.The control group was followed up for 5-121 months,with a median follow-up of 67 months.Within 5 years,28 cases died,10 cases had local recurrence,5 cases had regional recurrence,and 24 cases had distant metastasis,the 5-year LRFS,RRFS,DMFS and overall survival rates were 94.2%,97.1%,86.7%,84.7%,respectively.There were no significant differences in LRFS,RRFS,DMFS and overall survival between the two groups(P>0.05).The average radiation dose to the oral cavity of the observation group was significantly lower than that of the control group(P<0.01),and the minimum,average and maximum radiation doses to the larynx were significantly lower than those of the control group(P<0.01).Both groups completed radiotherapy as planned,and no grade Ⅳ mucosal reactions occurred,the observation group mainly developed grades Ⅰ and Ⅱ acute oral mucosal reactions,and the incidence of grade Ⅲ acute oral mucosal reactions was significantly lower than that in the control group(P<0.01).There were no significant differences in the incidence of late dry mouth and late dysphagia between the two groups(P>0.05).Conclusion Non-prophylactic irradiation of the retropharyngeal lymph nodes in the medial nasopharyngeal carcinoma group significantly reduced the average dose of radiation to the oral cavity and larynx,thereby reducing the risk of grade 3 acute mucositis,which is beneficial to protect swallowing-related structures,and does not affect disease control and survival.