腹部三维适形放疗患者的固定技术与摆位

三维适形放疗在世界范围已逐渐成为放射治疗的常规技术，它能使治疗区的形状与靶区的形状一致，从三维方向上进行剂量分布的控制，提高局部的控制率，减少正常组织的照射剂量。在放射治疗中，定位和摆位的技术水平，直接影响放射治疗的效果，不同程度的放疗并发症直接影响病人的生存质量。现将腹部适形放疗患者的固定与摆位技术介绍如下：     

晚期肺癌三维适形放疗31例临床分析

目的探讨晚期肺癌三维适形放疗方式及预后。方法对31例晚期肺癌患者资料进行回顾性分析。根据放疗方法的不同分为普通放疗(RT)+三维适形放疗(3DCRT)组10例、单纯三维适形放疗组21例,分析不同放疗方法的生存质量和生存率。结果 RT+3DCRT组、单纯3DCRT组的治疗有效率分别为90%,95.2%;1年生存率分别为20%、12.9%;相互比较均无显著性差异,但生存质量均有明显提高。结论 3DCRT可使晚期肺癌患者局部控制率提高,生活质量改善。     

肺癌三维适形放疗后的CT对比观察

肺癌的发病率居高不下，治疗方法多种多样，对于那些不宜以及不愿手术和化疗的中老年患者来说，放疗是一种切实有效的治疗方法，传统的放疗副作用大，近年来三维适形放疗发挥了越来越大的优势，笔者对我院进行了三维适形放疗的一组肺癌患者做了研究，观察了肺癌治疗前后的CT表现，获得了一些有价值的认识，提高了我们对三维适形放疗的认识。     

食道癌调强放疗与三维适形放疗的剂量学对比

目的比较食道癌在调强放疗与三维适形放疗中靶区剂量及正常组织照射量。方法从我院食道癌患者中抽取10例并由同一肿瘤医师在定位图像上勾画靶区及正常组织,在所勾画的靶区上分别作调强计划与三维适形计划,并以PTV95%、GTV95%、CI、HI、脊髓最大剂量以及左右肺V20来作为剂量评估指标,并进行统计学分析。结果统计学分析结果表明,三维适形放疗与调强放疗的各项指标之间的差异均有统计学意义。结论调强放疗在食道癌的治疗中无论是从靶区剂量的调控还是正常组织剂量的约束上都明显优于三维适形放疗,是食道癌放射治疗中的一种有效治疗方案。     

肝癌三维适形放疗进展

三维适形放疗(3DCRT)是一种提高治疗增益比的较为有效的放疗技术,已被广泛用于全身各部位肿瘤的治疗,也为不宜手术的中晚期原发性肝癌或转移性肝癌患者的放疗提供了一个新的治疗途径,且效果十分明显。3DCRT联合动脉导管化疗栓塞(TACE)与3DCRT联合热疗对治疗原发性肝癌有明显的治疗效果,而三者联合可发挥各自的优势,治疗效果更加显著。     

鼻咽癌三维适形和调强适形放疗研究现状

适形放疗是目前放疗领域的前沿课题，其中调强适形放疗(IMRT)是三维适形放疗(3DCRT)的高级阶段，是医用直线加速器使用以来，放疗领域的重要的技术进步。3DCRT/IMRT不仅是对现行的肿瘤放疗技术的一种补充，更为放射肿瘤学家提供了改变放疗惯例的根本性方法。     

PET／CT图像融合在肺癌三维适形放疗计划中的应用和价值

图像融合技术已广泛地应用于肺癌三维适形放疗计划的制定,特别是以PET为代表的功能性影像与CT的融合日益受到大家重视。应用PET/CT图像融合制定放疗计划既可以发挥PET在肺癌诊断、分期方面的优势,又可以发挥CT显示解剖结构方面的优势,使靶区勾画的准确性提高,同时正常组织和危险器官又能得到更为有效的保护。     

PET/CT图像融合在肺癌三维适形放疗计划中的应用和价值

图像融合技术已广泛地应用于肺癌三维适形放疗计划的制定,特别是以PET为代表的功能性影像与CT的融合日益受到大家重视.应用PET/CT图像融合制定放疗计划既可以发挥PET在肺癌诊断、分期方面的优势,又可以发挥CT显示解剖结构方面的优势,使靶区勾画的准确性提高,同时正常组织和危险器官又能得到更为有效的保护.     

直肠癌术前放疗中三维适形放疗与调强适形放疗的剂量学比较分析

目的 比较三维适形放疗(3D-CRT)与5野、7野调强适形放疗(IMRT)的剂量分布,以探讨IMRT对直肠癌术前放疗的价值。方法 对10例术前新辅助放化疗直肠癌患者,分别设计3D- CRT、5野IMRT、7野IMRT计划,应用剂量体积直方图(DVH),比较3种治疗计划的靶区适形度指数(CI)、不均匀性指数(HI)和正常器官受量。结果 适形度指数(CI)7野IMRT计划＞5野IMRT＞3D- CRT,不均匀性指数(HI)5野IMRT计划＞7野IMRT＞3D- CRT。5野、7野IMRT计划比3D- CRT均可以减少高剂量照射小肠、膀胱、股骨头体积,7野IMRT计划比5野可以减少高剂量照射的骨髓和膀胱的体积。结论 直肠癌术前放疗中IMRT计划在靶区剂量适形度方面均优于3D- CRT计划,对正常组织的保护也存在明显的优势。7野IMRT计划较5野IMRT计划技术有更好的剂量适形度与剂量均匀性。     

直肠癌术前放疗中三维适形放疗与调强适形放疗的剂量学比较分析

Objective To compare the dose distribution of the three-dimensional conformal radiotherapy(3D-CRT)and 5-field or 7-field intensity modulated radiation therapy(IMRT), and to explore the value of IMRT in preoperative radiotherapy for rectal cancer.Methods Ten rectal cancer patients treated with preoperative combination radiotherapy and chemotherapy were enrolled in this study. 3D-CRT plan and the 5.field or 7-field IMRT plans were performed for each patient.The conformal index (CI),heterogeneity index(HI)of the planning target volume(PTV)and the dose of normal organs of 3D-CRT plan(3D-CRTp)and the 5-field or 7-field IMRT plans(IMRT5fp or IMRT7fp)were analyzed with the dose-volume histogram.Results The CI values of PTV were 0.91,0.87 and 0.78 in IMRT7fpIMRT5fp and 3D- CRT but with IMRT7fp>IMRT5fp>3D-CRTp(t=-5.69、-8.91,P<0.01),respectively.The HI values of PrV were 1.09,1.08 and 1.05 in IMRT5fp,IMRT7fp and 3D- CRTp but with IMRT5fp >IMRT7fp>3D- CRTp(t=3.41、-6.89,P<0.01),respectively.The ratio of dose volume were 0.08,0.10 and 0.19(t=2.79、3.52,P<0.05)in IMRT7fp,IMRT5fp and 3D- CRTp on the small intestine V50,with 0.07,0.10 and 0.19(t=2.58、3.40,P<0.05)in IMRT7fp,IMRT5fp and 3D-CRTp on the bladder V50 and 0.01,0.01 and 0.05(t=3.00、3.17,P<0.01)in IMRT7fp,IMRT5fp and 3D- CRTp on the fomoral head V45.The ratio of dose volume were 0.31 and 0.38(t=3.91,P<0.01)in IMRT7fp and IMRT5fp on the bone marrow V50,with 0.07 and 0.10 in IMRT7fp and IMRT5fp on bladder V45.Conclusions IMRT plan is superior to 3 D- CRT plan in dose conformal degrees of PTV with preoperative radiotherapy of rectal cancer and can significantly protect the normal tissues.The 7-field IMRT plan might be the optimal plan for dose conformal degree and dose uniformity compared with 5-field IMRT.     

胸中段食管癌适形调强放疗和三维适形放疗方案的应用探讨

目的比较胸中段食管癌适形调强放疗(IMRT)和三维适形放疗(3D-CRT)两种不同技术中计划靶区(PTV)及正常组织的受量。方法对52例ⅡB-Ⅳ期胸中段食管癌患者用同一放疗计划系统分别设计IMRT和3D-CRT根治性放疗计划,应用剂量体积直方图(DVH)比较两种方法中计划靶区和正常组织受量并且计算计划靶区适形指数(CI)和剂量不均匀指数(HI)。结果 IMRT方法的PTV适形度优于3D-CRT;脊髓剂量的最大值低于3D-CRT,但无统计学差异;心脏接受V25和V40的体积百分比低于3D-CRT;IMRT显著降低了肺部V10和V20的有效体积,但其肺部的V5大于3D-CRT。结论在可接受的放射性损伤的基础上,IMRT技术较3D-CRT能够提高行根治性放疗的ⅡB-Ⅳ期胸中段食管癌患者靶区剂量,靶区适形度高,但可使肺组织受到更大容积的低剂量照射。     

A detailed evaluation of TomoDirect 3DCRT planning for whole-breast radiation therapy

The goal of this work was to develop planning strategies for whole-breast radiotherapy (WBRT) using TomoDirect three-dimensional conformal radiation therapy (TD-3DCRT) and to compare TD-3DCRT with conventional 3DCRT and TD intensity-modulated radiation therapy (TD-IMRT) to evaluate differences in WBRT plan quality. Computed tomography (CT) images of 10 women were used to generate 150 WBRT plans, varying in target structures, field width (FW), pitch, and number of beams. Effects on target and external maximum doses (EMD), organ-at-risk (OAR) doses, and treatment time were assessed for each parameter to establish an optimal planning technique. Using this technique, TD-3DCRT plans were generated and compared with TD-IMRT and standard 3DCRT plans. FW 5.0 cm with pitch = 0.250 cm significantly decreased EMD without increasing lung V20 Gy. Increasing number of beams from 2 to 6 and using an additional breast planning structure decreased EMD though increased lung V20 Gy. Changes in pitch had minimal effect on plan metrics. TD-3DCRT plans were subsequently generated using FW 5.0 cm, pitch = 0.250 cm, and 2 beams, with additional beams or planning structures added to decrease EMD when necessary. TD-3DCRT and TD-IMRT significantly decreased target maximum dose compared to standard 3DCRT. FW 5.0 cm with 2 to 6 beams or novel planning structures or both allow for TD-3DCRT WBRT plans with excellent target coverage and OAR doses. TD-3DCRT plans are comparable to plans generated using TD-IMRT and provide an alternative to conventional 3DCRT for WBRT.     

早期非小细胞肺癌三维适形放射治疗的疗效

目的探讨三维适形放射治疗早期非小细胞肺癌的疗效和放射反应。方法对36例临床Ⅰ—Ⅱ非小细胞肺癌行三维适形放射治疗，病人年龄58—88岁，中位年龄74岁，Ⅰ期25例，Ⅱ期11例，病灶小于3cm17例，3cm以上19例。采用真空袋固定，Philips公司CT模拟机定位及YARIAN公司的Eclipse三维治疗计划。小于3cm病灶采用弧形照射结合2-3个适形固定野，剂量10-15Gy，次，共3—5次；3cm以上病灶采用非共面适形野，剂量5～8Gy／次，共6—12次，计划要求95％以上PTV体积接受95％以上剂量。按100％等剂量线计算处方剂量，全肺V20控制在≤25％。结果近期疗效中完全缓解（CR）率为53％，部分缓解（PR）率为36％，无进展（NR）率为11％，总有效率（CR＋PR）为89％。肿瘤直径小于3cm者CR率为76．5％，而3cm以上者CR率为31．5％，差异有统计学意义（P〈0．025）。1、2、3年生存率分别为83．3％、52．4％、38．5％。Ⅰ期、Ⅱ期1年生存率分别为96％、54．5％，差异有统计学意义（P〈0．01），2年生存率分别为57％、43％。放射性肺反应早期多为0级，Ⅰ级9例，Ⅱ级3例，晚期肺反应多为Ⅰ级，Ⅱ级6例，无Ⅱ级以上早期及晚期放射性肺损伤。结论三维适形放射治疗技术治疗早期非小细胞肺癌是安全、有效的，具有较好的近期及远期疗效，失败原因主要为远处转移。     

CT误诊外围型肺癌20例分析

文章对20例经手术病理证实为CT误诊病例进行了分析。认为误诊原因为:1.窗口技术不适当、对肺癌的征象判断不准确;2.忽视综合分析为诊断原则;3.对形态不典型的外围型肺癌认识不足。作者认为易导致误诊的是早期外围型肺癌;与肺结核并存的肺癌;类似机化性肺炎或肺良性肿瘤的肺癌;不按肺癌倍增时间生长的肺癌。文中重点讨论了外围型肺癌与肺结核和慢性肺炎的鉴别诊断。作者强调外围型肺癌的各种CT征象中无一项具有特异性诊断价值,提高肺癌诊断准确率的关键仍是影象所见结合临床、具体分析、综合诊断。     

Clinical Implementation of Tangential Field Intensity Modulated Radiation Therapy (IMRT) Using Sliding Window Technique and Dosimetric Comparison with 3D Conformal Therapy (3DCRT) in Breast Cancer

The purpose of this study was to evaluate the clinical implementation of tangential field IMRT using sliding window technique and to compare dosimetric parameters with 3-dimensional conformal radiation therapy (3DCRT). Twenty breast cancer patients were randomly selected for comparison of intensity modulated radiation therapy (IMRT)-based treatment plan with 3DCRT. Inverse treatment was performed using the sliding window technique, employing the Eclipse^® Planning System (version 7.1.59, Varian, Palo Alto, CA). The dosimetric parameters compared were V₉₅ (the percentage of target volume getting ≥95% of prescribed dose), V₁₀₅, V₁₁₀, and dose homogeneity index, DHI (percentage of target volume getting between 95% and 110% of prescribed dose). The mean V₉₅, DHI, V₁₀₅, and V₁₁₀ for target volume for IMRT vs. 3D were 90.6% (standard deviation [SD]: 3.2) vs. 91% (SD: 3.0), 87.7 (SD: 6.0) vs. 82.6 (SD: 7.8), 27.3% (SD: 20.3) vs. 49.4% (SD: 14.3), and 2.8 (SD: 5.6) vs. 8.4% (SD: 7.4), respectively. DHI was increased by 6.3% with IMRT compared to 3DCRT (p < 0.05). The reductions of V₁₀₅ and V₁₁₀ for the IMRT compared to 3DCRT were 44.7% and 66.3%, respectively (p < 0.01). The mean dose and V₃₀ for heart with IMRT were 2.3 (SD: 1.1) and 1.05 (SD: 1.5) respectively, which was a reduction by 6.8% and 7.9%, respectively, in comparison with 3D. Similarly, the mean dose and V₂₀ for the ipsilateral lung and the percentage of volume of contralateral volume lung receiving > 5% of prescribed dose with IMRT were reduced by 9.9%, 2.2%, and 35%, respectively. The mean of total monitor units used for IMRT and 3DCRT was about the same (397 vs. 387). The tangential field IMRT for intact breast using sliding window technique was successfully implemented in the clinic. We have now treated more than 1000 breast cancer patients with this technique. The dosimetric data suggest improved dose homogeneity in the breast and reduction in the dose to lung and heart for IMRT treatments, which may be of clinical value in potentially contributing to improved cosmetic results and reduced late treatment-related toxicity.     

Clinical Implementation of Tangential Field Intensity Modulated Radiation Therapy (IMRT) Using Sliding Window Technique and Dosimetric Comparison with 3D Conformal Therapy (3DCRT) in Breast Cancer

The purpose of this study was to evaluate the clinical implementation of tangential field IMRT using sliding window technique and to compare dosimetric parameters with 3-dimensional conformal radiation therapy (3DCRT). Twenty breast cancer patients were randomly selected for comparison of intensity modulated radiation therapy (IMRT)-based treatment plan with 3DCRT. Inverse treatment was performed using the sliding window technique, employing the Eclipse^® Planning System (version 7.1.59, Varian, Palo Alto, CA). The dosimetric parameters compared were V₉₅ (the percentage of target volume getting ≥95% of prescribed dose), V₁₀₅, V₁₁₀, and dose homogeneity index, DHI (percentage of target volume getting between 95% and 110% of prescribed dose). The mean V₉₅, DHI, V₁₀₅, and V₁₁₀ for target volume for IMRT vs. 3D were 90.6% (standard deviation [SD]: 3.2) vs. 91% (SD: 3.0), 87.7 (SD: 6.0) vs. 82.6 (SD: 7.8), 27.3% (SD: 20.3) vs. 49.4% (SD: 14.3), and 2.8 (SD: 5.6) vs. 8.4% (SD: 7.4), respectively. DHI was increased by 6.3% with IMRT compared to 3DCRT (p < 0.05). The reductions of V₁₀₅ and V₁₁₀ for the IMRT compared to 3DCRT were 44.7% and 66.3%, respectively (p < 0.01). The mean dose and V₃₀ for heart with IMRT were 2.3 (SD: 1.1) and 1.05 (SD: 1.5) respectively, which was a reduction by 6.8% and 7.9%, respectively, in comparison with 3D. Similarly, the mean dose and V₂₀ for the ipsilateral lung and the percentage of volume of contralateral volume lung receiving > 5% of prescribed dose with IMRT were reduced by 9.9%, 2.2%, and 35%, respectively. The mean of total monitor units used for IMRT and 3DCRT was about the same (397 vs. 387). The tangential field IMRT for intact breast using sliding window technique was successfully implemented in the clinic. We have now treated more than 1000 breast cancer patients with this technique. The dosimetric data suggest improved dose homogeneity in the breast and reduction in the dose to lung and heart for IMRT treatments, which may be of clinical value in potentially contributing to improved cosmetic results and reduced late treatment-related toxicity.     

膜式病变细胞采集术用于支气管肺泡灌洗液细胞学检查在周围型肺癌诊断中的价值

目的 评价膜式病变细胞采集制片技术用于支气管肺泡灌洗液(BALF)细胞学检查对周围型肺癌的诊断价值.方法 收集115例周围型肺癌患者经纤支镜取支气管肺泡灌洗液分别用膜式病变细胞采集术及常规离心涂片细胞学检查与钳取活检、刷片病理学检查对比.结果 用膜式病变细胞采集术收集处理BALF癌细胞阳性率占(71.30%),与常规离心涂片癌细胞阳性率占(69.47%)相比,P>0.01,与钳取活检(40.87%),刷片(35.65%)相比,P<0.01.结论 BALF细胞学检查对周围型肺癌具有较好的诊断价值,膜式病变细胞采集制片技术用于支气管肺泡灌洗液细胞学检查有助于阅片及病理诊断.     

周围型支气管肺癌HRCT界面影像不对称分布的病理基础

目的　研究周围型肺癌 (peripherallungcancer ,PLC)瘤—肺界面影像不对称分布的病理基础。方法　将病理证实的 2 5例周围型肺癌及 16例肺良性结节的病灶肺叶术后标本行Heitsman法固定 48～ 72h后HRCT扫描 ,再将标本制成含病灶肺全叶切片及病灶组织切片进行对照研究 ,观察瘤—肺界面HRCT表现的病理基础。结果　术后标本HRCT、大体病理切片的变化完全吻合。PLC近端边缘模糊 4例 (16% ) ,细毛刺 3例 (12 % ) ,远端分别为 18例 (72 % )、19例 (76% ) ,呈明显不对称分布 (Ρ <0 .0 1)。肺良性结节近端病灶边缘出现上述改变者各 3例 ,远端分别为 2例、3例 ,两者之间分布无差异 (Ρ >0 .0 5 )。远端瘤—肺界面显示不对称分布组织病理学主要表现为慢性阻塞性肺炎、肺间质纤维组织增生、淋巴管炎及癌细胞浸润。癌灶与支气管间的关系为支 (细 )气管腔完全阻塞 9例 ,管腔偏心性狭窄 >5 0 % 12例 ,管腔无明显变化但出现毛刺等变化 3例。良性病灶附近支 (细 )气管主要表现为受压、移位、绕行 ,管腔无明显狭窄或截断。病灶周边组织学变化主要为变性的纤维组织包膜及受病灶压迫萎陷的肺泡组织。结论　周围型肺癌界面影像改变不对称分布的病理基础是癌灶所致的支气管阻塞及导致癌结节远端与肺交界面的淋巴管回流障碍、     

非小细胞肺癌适形放射治疗中急性放射性食管炎影响因素的研究

目的 探讨接受三维适形放疗(3D-CRT)的非小细胞肺癌(NSCLC)患者发生≥2级急性放射性食管炎(ARE)的影响因素。方法 回顾102例接受3D-CRT的NSCLC患者的临床资料及三维计划资料,采用RTOG分级标准,评价患者自放疗开始3个月内≥2级的ARE。分析临床因素和三维计划的剂量体积参数。结果 发生2级ARE19例,3级15例,未出现更严重的ARE。非同步化疗组多因素回归分析显示,食管V55(OR=1.170,P<0.05)为≥2级ARE发生的惟一影响因素,食管V55的ROC曲线下面积为0.870(95%CI: 0.782~0.957,P＜0.05),界值为16.0。同步化疗组多因素回归分析显示,食管V₃₅(OR=1.125,P<0.05)和同步化疗方案(OR=39.740,P<0.05)是≥2级ARE发生的影响因素,食管V₃₅的ROC曲线下面积为0.782(95%CI: 0.636~0.927,P<0.05),界值为23.75。长春瑞滨+顺铂(NP)同步化疗方案的≥2级ARE发生率明显低于其他方案(33.3% ∶66.7%)。结论 非同步化疗患者,食管V55是≥2级ARE的影响因素。同步化疗患者,食管V₃₅和同步化疗方案是≥2级ARE的影响因素。同步NP方案≥2级ARE发生率较低。