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目的 探讨在颅脑多发转移瘤中,不同射野角度对逆向调强放疗计划剂量的影响及射野角度优化的可行性。方法 单纯随机取样法选取11例多发脑转移瘤患者,采用射野角度优化逆向调强计划(BAO组),并与射野角度均分逆向调强计划(BAF组)进行比较,统计分析危及器官和正常组织的受照剂量、靶区剂量分布及机器跳数,分析不同射野角度引起的剂量学差异。结果 与BAF组相比,BAO组中左、右眼晶状体最大受照剂量降低了45%、37%(t=-5.707、-4.438,P<0.05);左、右眼球平均受照剂量分别降低了42.6%、44.5%(t=-4.380、-5.638,P<0.05);右侧眼球的最大剂量平均降低32.5%(t=-2.518,P<0.05);右侧视神经的最大剂量降低了23%(t=-3.105,P<0.05);正常脑组织平均受量降低了3%(t=-3.437,P<0.05)。两组逆向调强计划的靶区剂量、适形度和均匀性指数差异无统计学意义(P>0.05)。角度优化逆向调强计划降低了脑干、视交叉的最大受照剂量和机器跳数,但两组结果差异无统计学意义(P>0.05)。结论 射野角度优化后的逆向调强计划,可保持与射野角度均分的逆向调强计划相当的靶区剂量,同时降低了部分危及器官的受照剂量。对于多发脑转移瘤,射野角度优化的逆向调强计划是可行且有益的。 相似文献
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Objective To evaluate the prognostic value of serial 18F-fluorodeexyglucose (FDG) PET/CT in patients with nasopharyngeal carcinoma (NPC).Methods Thirty-seven NPC patients who had 18F-FDG PET/CT scan before and after external beam intensity-modulated radiotherapy, were studied retrospectively.All patients were followed for five years.Correlation analysis between metabolic tumor volume (MTV)/uptake volume index (UVI) and survival was performed by Kaplan-Meier analysis, Log-rank test and multivariate Cox model.Results The 5-year overall survival (OS) and disease-free survival (DFS) rates were 70.3% (26/37) and 62.2% ( 23/37 ), respectively.Patients with a lower MTV (MTV<30 cm3) had significantly higher 5-year OS ( 82.6% ( 19/23 ) ) and DFS (73.9% ( 17/23 )) rates than those with a higher MTV (OS:50.0% (7/14),x2 =5.28, P<0.05; DFS:42.9% (6/14),x2 =4.84, P<0.05).Patients with a lower UV1 (UVI<150) had significantly higher 5-year OS( 87.5%( 21/24 )) and DFS (79.2% (19/24)) rates than those with a higher UVI (OS:38.5% (5/13),x2 =10.72, P<0.01;DFS:30.8% (4/13), x2 =11.04, P<0.01).Multivariate analysis showed that UVI and metabolic response (MR) were independent predictors of DFS.Conclusions Tumor volume parameters, UVI and MR, are independent prognostic factors for patients with NPC.Patients with a high UVI may benefit from more aggressive treatment. 相似文献
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目的 利用AdEasy系统构建低氧射线双调控的TK表达载体- 腺病毒Ad.HRE.CArG.HSV-TK,并观察其对人乳腺癌细胞系Bcap37和MDA-MB-435的放射增敏作用。方法 用分子克隆技术构建插入HRE.CArG.HSV-TK片段的Ad.HRE.CArG.HSV-TK。CsCl梯度离心法纯化病毒,用AdEasy系统GFP标签测定病毒功能滴度。Ad.HRE.CArG.HSV-TK体外转导细胞48h,流式细胞仪测GFP阳性率,Real-time RT-PCR和Western blot检测TK mRNA和蛋白表达。MTT法检测腺病毒(Ad)转导联合放射(RT)对细胞的生长抑制作用和放射增敏比(SER)。结果 Ad.HRE.CArG.HSV-TK 滴度为2.1×109TU/mL。50 MOI病毒转导Bcap37和MDA-MB-435细胞48h,GFP阳性率分别为92%和93%,TK基因表达明显增加(P<0.05)。Ad与RT联用组(Ad+RT)组细胞生长抑制率明显高于Ad组和相应同等剂量RT组(P<0.05),SER为1.55。结论 应用AdEasy系统可制备同时表达GFP和TK的重组腺病毒。腺病毒对乳腺癌细胞具放射增敏作用,为进一步开展乳腺癌的基因放射治疗奠定基础。 相似文献
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目的探讨食管鳞癌FDG PET显像的最大标准摄取值(maximum FDG PET standardized uptake value,SUVmax)与肿瘤Ki-67表达及病理分级的关系。方法食管癌患者47例,于术前1周内行18F-FDG PET/CT检查,测得SUVmax。术后取得肿瘤标本,行Ki-67免疫组织化学染色,并HE染色确定病理分级,分析SUVmax、Ki-67、病理分级之间的关系。结果 (1)47例患者中共47个食管鳞癌原发病灶,SUVmax为1.9~24.0,平均为12.504±6.805,Ki-67平均指数为(67.837±29.798)%,经统计学分析,SUVmax与Ki-67指数呈正相关r,值为0.581,P〈0.05。(2)47例中高分化鳞癌13例,中分化鳞癌16例,低分化鳞癌18例。高、中、分化鳞癌的平均SUVmax分别为9.787±1.4771、2.313±0.479和15.053±2.147,经统计学分析,三者之间差异均有统计学意义(P=0.000)。结论 SUVmax可间接评价食管癌细胞的增殖能力,SUVmax在一定程度上能够反映肿瘤的病理分级。 相似文献
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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. 相似文献
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目的:观察乏氧状态下干扰锌指转录因子Snail对人肺腺癌SPCA1细胞侵袭的影响及其上皮一间质转化(epi—thelial mesenehymal transition,EMT)相关分子机制。方法:应用靶向人Snail基因的小干扰RNA(Snail siRNA)转染常氧(19%O2)肺癌细胞,48h后将细胞置乏氧(0.5%O2)培养箱培养,乏氧24h后采用Real—Time PCR检测细胞SnailmRNA表达,蛋白质印迹法检测Snail和EMT表型分子E一钙黏素蛋白表达,Transwell小室评价细胞侵袭能力。结果:与常氧细胞(设为1)相比,乏氧诱导肺癌SPCAl细胞Snail mRNA(5.31±0.73)和蛋白(4.82±0.67)表达均显著增加,P均〈0.05。与乏氧对照siRNA组(设为1)比较,LOX siRNA转染后乏氧SPCAl细胞SnailmRNA和蛋白表达分别为0.26±0.08和0.28±0.03。将常氧细胞侵袭力和E-钙黏素表达设为1,则乏氧细胞侵袭力和E-钙黏素表达分别为1.85±0.13和0.45±0.04,与常氧细胞存在显著差异,P值均〈0.05。下调Snail表达后,乏氧细胞侵袭力和E-钙黏素表达分别为0.90±0.08和1.81±0.09,与乏氧对照s.RNA组存在显著差异,P值均〈0.05。将乏氧对照siRNA细胞侵袭力和E-钙黏素表达设为1,则SnailsiRNA组侵袭力和E-钙黏素分别为0.50±0.03和2.04±0.17,P值均〈0.05。结论:乏氧状态下干扰Snail降低肺癌细胞侵袭,其机制可能与增加E-钙黏素蛋白表达有关。 相似文献
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目的 探讨胸部肿瘤患者三维放疗前后血清心肌酶谱改变与心脏体积剂量的相关性。方法 102例胸部肿瘤患者(肺癌 68例、食管癌 34例)放疗前后检测血清天冬氨酸氨基转移酶(AST)、肌酸激酶(CK)、CK同工酶(CK-MB)、乳酸脱氢酶(LDH)及α-羟丁酸脱氢酶(α-HBDH)水平。放疗前后各种酶水平比较行配对t检验,组间比较行成组t检验。采用剂量体积直方图(DVH)参数\[心脏接受≥x Gy照射体积占总体积百分比(Vx)\]评价心脏体积剂量,各种酶与DVH参数相关性行Pearson法分析。结果 放疗后血清AST、CK-MB、LDH、α-HBDH水平较放疗前明显增高(19.42∶27.89、14.72∶19.57、178.80∶217.57、140.32∶176.25,t=-3.39~-6.92,P均=0.000)。调强放疗前后AST变化与 V20、V25、V30相关(r=0.302~0.431,P=0.039~0.003),CK变化与 V30相关(r=0.345,P=0.013),CK-MB、LDH、α-HBDH变化与 V25、V30均相关(r=0.465~0.376,P=0.001~0.005);三维适形放疗前后CK-MB、LDH变化与 V30相关(r=0.330、0.274,P=0.014、0.033),α-HBDH变化与 V25、V30、V35相关(r=0.270~0.331,P=0.046~0.014)。当放疗剂量>50 Gy时AST、LDH、α-HBDH变化与 V25、V30相关(r=0.256~0.359,P=0.019~0.006),CK-MB变化与 V30相关(r=0.233,P=0.037);≤50 Gy时仅 V5、V45与CK变化相关(r=0.581、0.536,P=0.023、0.043)。结论 心脏体积剂量与三维放疗前后心肌酶水平变化有一定相关性,提示心脏DVH参数有助于评价放疗诱导的心肌损伤。 相似文献