局部晚期非小细胞肺癌同步放化疗原发肿瘤与转移淋巴结退缩差异分析

Shrinkage heterogeneity between primary tumor and regionally-metastasized lymph nodes in locally advanced non-small cell lung cancer treated by chemoradiotherapy

目的同步放化疗是局部晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)的标准治疗模式,基于区域肿瘤控制的影像引导个体化对待是局部晚期NSCLC放疗的研究热点。本研究旨在探讨局部晚期NSCLC接受同步放化疗后原发肿瘤与转移淋巴结体积退缩率(volumetric shrinkage rate,VSR)的差异及与治疗前FDG PET-CT代谢参数的关联性。方法选择2014-07-01-2016-12-31山东省肿瘤医院接受同步放化疗的局部晚期NSCLC患者为研究对象,筛选出32例符合条件的治疗前4周内行FDG PET-CT检查并行同步放化疗且放疗总剂量≥50Gy患者入组,在MIM软件系统中,分别基于治疗前定位CT和治疗结束后首次随访CT勾画原发肿瘤及转移淋巴结体积(gross tumor volume,GTV),并在治疗前FDG PET-CT图像上勾画原发肿瘤和转移淋巴结,计算原发肿瘤及转移淋巴结VSR及近期有效率(overall response rate,ORR),统计分析代谢参数等变量与VSR及ORR的关系。结果原发肿瘤VSR(中位数66.49%,范围-20.73%~96.04%)显著高于转移淋巴结VSR(中位数48.78%,范围-220.00%~99.46%),z=-2.619,P=0.009;转移淋巴结最大SUV值(maximum standard uptake value of regionally-involved lymph node,SUVmax-nd)是影响原发肿瘤与转移淋巴结VSR差异的唯一因素,OR=1.445,95%CI为0.891~2.344。原发肿瘤ORR为56.3%,高于转移淋巴结31.0%,χ2=6.326,P=0.012,对于所有病灶而言,SUVmax是影响NSCLC肿瘤病灶ORR差异的唯一因素,OR=0.845,95%CI为0.761~0.939。结论局部晚期NSCLC同步放化疗结束时,原发肿瘤VSR显著高于转移淋巴结,治疗前SUVmax-nd可以作为预测这种差异的变量,同样,SUVmax是预测NSCLC同步放化疗近期疗效的有效变量。

OBJECTIVE Image-guided individual treatment based on regional tumor control rate has been a research hotspot of locally-advanced non-small cell lung cancer（NSCLC）.Concurrent chemoradiotherapy has become standard treatment for locally advanced NSCLC.The objective of this study was to investigate whether there was dissimilarity of volumetric shrinkage rate（VSR）between primary tumor and regionally-metastasized lymph nodes of locally advanced NSCLC treated by concurrent chemoradiotherapy and to explore the influential factors.METHODS A retrospective review identified patients diagnosed with locally advanced NSCLC in Shandong Cancer Hospital between July 1,2014 and December 31,2016.Thirty-two patients who both underwent baseline 18 F-FDG PET-CT scan within 4 weeks before treatment and treated with concurrent chemoradiotherapy were enrolled.All enrolled patients received at least 50 Gy units of radiation.The target lesions were delineated on each patient＇s PET and CT images（enhanced planning CT and followup CT）respectively.Parameters such as metabolism parameters were automatically calculated and output as a table by MIM software.VSR and overall response rate（ORR）was calculated from gross tumor volume（GTV）delineated on CT scans.Relationship between VSR or ORR and metabolism parameters were analyzed.RESULTS（1）The average VSR of primary tumor was significantly higher than the average VSR of regionally-metastasized lymph nodes（59.8% vs34.14%,z=-2.619,P=0.009）.SUVmax-nd（maximum standard uptake value of regionally-metastasized lymph node）was the only significant influential factor to VSR in multivariate analysis（OR=1.445,95%CI：0.891-2.344）.（2）ORR in primary tumor was 56.3%and in regionally-metastasized lymph nodes was 31.0%.ORR was much more significant in primary tumor（χ^2=6.326,P=0.012）.Similarly,SUVmax was the only significant influential factor to all NSCLC lesions in multivariate analysis（OR=0.845,95%CI：0.761-0.939）.CONCLUSIONS In locally advanced NSCLC with concurrent chemoradiotherapy,VSR in primary tumor was more pronounced than regionally-involved lymph nodes and pretreatment SUVmax may be a predictive variable.Similarly,SUVmax-ndwas an effective prognostic factor for short-term-efficacy of locally-advanced NSCLC treated with concurrent chemoradiotherapy.