食管鳞状细胞癌FDG PET/CT显像SUVmax与肿瘤增殖、侵袭和血管生成的关系

目的 探讨食管鳞状细胞癌(简称鳞癌)FDG PET/CT显像SUVmax与肿瘤细胞Ki67、基质金属蛋白酶2(MMP-2)和微血管密度(MVD)的相关性,以评估SUVmax是否可作为术前反映肿瘤增殖活性、侵袭性和微血管生成的指标.方法 选择术后病理证实的食管鳞癌患者47例,术前1周内行18F-FDG PET/CT检查;术后对患者肿瘤标本行Ki67、MMP-2和MVD免疫组织化学染色,用Pearson 直线相关分析病灶SUVmax与上述指标的相关性.结果 47处病灶SUVmax为1.9 ～24.0,平均为12.504±6.805.免疫组织化学检查:Ki67平均指数为(67.837±29.798)％,MMP-2平均指数为(71.551 ±27.126)％,MVD平均为(18.429±9.603)个.SUVmax与Ki67指数、MMP-2指数间呈正相关,r值分别为0.581和0.594,P均＜0.05;而SUVmax与MVD之间不具有相关性,r=0.167,P＞0.05.结论 SUVmax可反映食管鳞癌肿瘤增殖活性和侵袭性,不能反映肿瘤血管生成.     

双示踪剂用于PET-CT图像勾画胸段食管癌生物靶区的模拟计划剂量学 比较

目的 探讨氟脱氧胸苷(FLT)PET-CT用于食管癌放疗计划的可行性,并与氟脱氧葡萄糖(FDG)PET-CT图像勾画生物靶区的模拟计划的剂量学进行比较.方法 对22例胸段食管癌患者分别行FLT、FDG PET-CT,在Philips Pinnacle3治疗计划系统中分别基于FLT、FDG PET-CT的最佳阈值图像进行靶区(GTV、CTV、PTV)勾画,并制定两种模拟放疗计划.在射野方向相同、保证处方剂量线包绕95%靶体积前提下,比较两组计划的剂量体积直方图参数.结果 基于FLT PET-CT计划的GTV、CTV和PTV小于FDG PET-CT的,分别为29.03 cm3∶33.05 cm3(t=-2.62,P＜0.05)、244.22 cm3∶257.01 cm3(t=-3.53,P＜0.05)和351.29 cm3∶379.85 cm3(t=-4.01,P＜0.05);而适形指数和均匀指数均相似,分别为0.74∶0.72(t=0.89,P＞0.05)和1.09∶1.11(t=1.41,P＞0.05);全肺V20、心脏V40和脊髓最大剂量也相似(t=-1.60、-1.55,P＞0.05).FLT PET-CT计划的平均肺受量、双肺V5、V10、V30、V40和V50、平均心脏受量和心脏V30明显低于FDG PET-CT的(t=-5.442～-2.637,P＜0.05).结论 两种示踪剂的PET-CT计划中靶区均能满足剂量要求,但FLTPET-CT的模拟计划会给心脏和肺带来潜在受益.

Abstract：

Objective To investigate a feasibility of treatment planning in thoracic esophageal carcinoma with 3-deoxy-3-fluorothymidine (FLT) PET-CT and to compare with fluorodeoxyglucose (FDG) PET-CT based on dosimetric analysis.MethodsTwenty-two patients with esophageal squamous cell carcinoma detected by FLT and FDG PET-CT were enrolled.The gross tumor volumes ( GTV ),clinical target volume(CTV) and planning target volume ( PTV ) were delineated using treatment planning system of Philips Pinnacle3 based on the optimal threshold of FLT and FDG PET-CT respectively,and to make two groups simulation treatment planning.The parameters of dose-volume histograms in two groups planning were compared in the similar direction and ensuring prescribed dose line surround 95% target volume.Results The values of GTV,CTV and PTV in FLT PET-CT planning were less than those of FDG,that dose received by spinal cord in two planning were not significantly yet ( t = - 1.60,- 1.55,all P ＞ 0.05 ).While,the values in mean lung dose,V5,V10,V30,V40 and V50 of bilateral lung,mean heart dose,and V30 of heart in FLT PET-CT planning were significant lower than those of FDG( t = -5.442 - -2.637,all P ＜0.05).Conclusions Compared with FDG,FLT PET-CT based treatment planning brings potential benefits for lungs and heart.