食管癌累及野照射时淋巴结引流区IID与复发关系的初步研究

目的 探讨食管癌三维适形累及野照射(IFI)时相应淋巴结引流区不经意照射剂量(IID)与复发的关系。方法 回顾分析2000—2004年间接受根治性放疗的 81例食管癌患者资料,分析治疗失败模式、IID大小及IID大小与复发及患者长期生存的关系等。Kaplan-Meier法计算OS、LC率并Logrank法检验,ROC曲线分析V_PTV-NX的预测价值,Spearman法相关分析。结果 随访率100%。1、3、5、 8年 OS和LC分别为68%、33%、21%、11%和77%、46%、36%、20%。治疗后单纯局部区域复发 21例 ,单纯远处转移 15例 ,复发伴远处转移 3例 。ROC曲线分析结果显示V_PTV-N40~50能有效预测野外复发( P= 0. 004~ 0.031),其预测最佳临界点值分别为71.5%、68.5%和58.5%。V_PTV-N40~50大小与患者长期OS无关( P= 0. 601~ 0.826),但与照射野外复发显著相关( P= 0. 005~ 0.010)。V_PTV-N40~50大小与≥2级放射性损伤均无关(r= 0.151~ 0.027, P= 0.108~ 0.809)。结论 食管癌接受三维适形IFI时其相应淋巴结引流区所得较大的IID可能能起到预防亚临床病灶的作用。

A preliminary study of relationship between incidental irradiation dose to lymph node stations and recurrence in esophageal cancer patients treated by involved-field irradiation

Objective To investigate the relationship between the incidental irradiation dose (IID) to lymph node stations and recurrence in esophageal cancer (EC) patients treated by involved-field irradiation (IFI). Methods A retrospective analysis was performed on the clinical data of 81 EC patients who received radical radiotherapy from 2000 to 2004. The treatment failure mode, IID, and the relationship of IID with recurrence and long-term survival were analyzed. The Kaplan-Meier method was used to calculate overall survival (OS) and local control (LC) rates, and the log-rank test was used for survival difference analysis;the prognostic value of V_PTV-NX was determined by receiver operating characteristic (ROC) analysis, and correlation analysis was performed by Spearman method. Results The follow-up rate was 100%. The 1-, 3-, 5-, and 8-year OS rates were 68%, 33%, 21%, and 11%, respectively, and the 1-, 3-, 5-, and 8-year LC rates were 77%, 46%, 36%, and 20%, respectively. After treatment, locoregional recurrence was found in 21 patients, distant metastasis in 15 patients, and recurrence and distant metastasis in 3 patients. The ROC analysis showed that V_PTV-N40~50 could effectively predict out-field recurrence (P=0.004—0.031), and the optimal cut-off values were 71.5%, 68.5%, and 58.5%, respectively. V_PTV-N40~50 had no significant correlation with long-term OS (P=0.601—0.f826), but showed a significant correlation with out-field recurrence (P=0.005—0.010). There was no significant correlationbetween V_PTV-NX and grade ≥2 radiation injury (r=0.151－0.027,P=0.108—0.809). ConclusionsConsiderable IID to lymph node stations near EC may contribute to the prevention of subclinical lesions in EC patients treated by IFI.