非小细胞肺癌肺门-叶间与纵隔淋巴结转移FDG PET SUVmax诊断阈值间的对比分析

摘要

目的 对比分析NSCLC患者肺门-叶间与纵隔淋巴结转移的FDG PET SUVmax诊断阈值,探讨其在NSCLC术前分期中的价值.方法 回顾性分析FDG PET/CT检查后1个月内行肿瘤切除并局部淋巴结清扫的69例(男40例、女29例,年龄36 ～ 87岁)N0～2期NSCLC患者资料.切除淋巴结的SUVmax与病理结果逐一对比分析.以ROC曲线获得诊断淋巴结转移的SUVmax阈值;采用Mann-Whitney u检验、x2检验和Fisher确切概率法分析数据.结果 69例患者中,肺门-叶间淋巴结和(或)纵隔淋巴结转移者21例.切除并获得病理结果的339枚淋巴结中,61枚有转移.转移淋巴结的SUVmax[4.95(3.46,7.19)]显著高于非转移淋巴结[2.10(1.59,3.22);z=-7.576,P＜0.05].肺门-叶间转移淋巴结的SUVmax [6.32(4.28,8.27)]显著高于纵隔转移淋巴结[3.90(2.12,6.41);z=-2.921,P＜0.05].以SUVmax≥2.5为标准,诊断淋巴结转移的灵敏度、特异性、准确性分别为83.6％ (51/61)、61.9％ (172/278)、65.8％ (223/339),诊断纵隔淋巴结转移的相应值分别为74.2％(23/31)、79.6％(160/201)和78.9％(183/232),诊断肺门-叶间淋巴结转移的相应值分别为93.3％ (28/30)、15.6％(12/77)和37.4％(40/107);2种转移的诊断灵敏度差异无统计学意义(Fisher确切概率法,P＞O.05),特异性和准确性差异有统计学意义(x2值:96.7和56.1,均P＜0.05).ROC曲线分析获得诊断纵隔转移淋巴结的SUVmax阈值为2.78,相应的灵敏度、特异性和准确性分别为71.0％(22/31)、87.1％(175/201)和84.9％ (197/232);诊断肺门-叶间转移淋巴结的SUVmax阈值为4.93,相应效能值分别为73.3％(22/30)、77.9％(60/77)和76.6％ (82/107).结论 以FDG PET SUVmax诊断NSCLC淋巴结转移,肺门-叶间、纵隔淋巴结转移分别使用不同的SUVmax阈值,能获得更准确的淋巴结分期结果.%Objective To study the FDG SUVmax cutoff values in detection of metastases in mediastinal lymph nodes (MLN) and hilar/intralobar lymph nodes (HILN) in pre-operative patients with N0-2 stage NSCLC.Methods A total of 69 patients with stage N0-2 NSCLC (40 males,29 females,age 36-87 years) were included in this retrospective study.18F-FDG PET/CT was performed and followed by lung cancer resection with lymph node dissection in 1 month.The excised lymph nodes were compared one by one between their SUVmax and histopathology.The SUVmax cutoff value in detection of lymph node metastases was determined by the ROC curve.Mann-Whitney u test,x2 test,and Fisher exact test were used for data analysis.Results Metastatic MLN and (or) HILN were found in 21 of 69 NSCLC patients.The histopathologic results demonstrated metastases in 61 of 339 lymph nodes.The SUVmax of metastatic lymph nodes (4.95(3.46,7.19)) was significantly higher than that of benign lymph nodes (2.10(1.59,3.22);z=-7.576,P＜0.05).The SUVmax of metastatic HILN (6.32 (4.28,8.27)) was significantly higher than that of metastatic MLN (3.90(2.12,6.41);z=-2.921,P＜0.05).With cutoff of SUVmax ≥2.5,the sensitivity,specificity and accuracy in detection of all metastatic lymph nodes were 83.6％ (51/61),61.9％ (172/278)and 65.8％ (223/339) respectively,and the parameters were 74.2％ (23/31),79.6％ (160/201) and 78.9％ (183/232) for metastatic MLN,and 93.3％ (28/30),15.6％ (12/77) and 37.4％ (40/107) for metastatic HILN.The diagnostic sensitivities for metastatic MLN and for metastatic HILN were not significantly different (Fisher exact test,P＞0.05),while the specificities and accuracies between the two groups were significantly different (x2 values:96.7 and 56.1,both P＜0.05).According to ROC curves,cutoff values of SUVmax in detecting metastatic MLN and metastatic HILN were 2.78 and 4.93.With the specific cutoff value,the sensitivity,specificity and accuracy in detection of metastatic MLN were 71.0％ (22/31),87.1％ (175/201)and 84.9％(197/232),respectively.The corresponding data in detection of metastatic HILN were 73.3％ (22/30),77.9％(60/77) and 76.6％(82/107).Conclusion Different cutoff values of SUVmax in detecting metastatic MLN and metastatic HILN should be considered for more accurate lymph nodes staging in patients with NSCLC.