多形性胶质母细胞瘤的手术与放射治疗

A retrospective analysis of 73 patients with glioblastoma multiforme treated with surgery plus radiotherapy (63 cases) or surgery alone (10 cases) showed that the 5-year survival was 16% versus 0% and the median survival time was 14 versus 5 months. The median survival time in patients receiving postoperative radiotherapy was almost 3 times as long as that in patients treated with surgery alone. The difference in survival was insignificant between patients treated with a local extended field and those with whole brain plus local irradiation. The age, sex, course of disease, extent of operation and dose of irradiation are the factors influencing prognosis.     

胶质母细胞瘤术后调强放疗靶区勾画进展

胶质母细胞瘤的标准治疗方案包括手术切除,术后放疗,并同期辅以替莫唑胺口服化疗。放疗与否同患者的生存时间直接相关,但放疗的靶区勾画标准仍存在极大争议。本文首先分析了国内外对临床靶区外放范围的不同观点,总结胶母细胞瘤放疗后的复发模式。其次,阐述了目前无法精确勾画外放边界的技术原因,并且我们认为参考患者的临床和病理特征来勾画一个个体化的放疗靶区非常重要。最后,本文探讨了放疗在胶母细胞瘤中的应用前景,旨在勾画更为精确的放疗靶区使患者最大获益。     

多形性胶质母细胞瘤放疗临床靶区范围及治疗的讨论

间变性星形细胞瘤为WHO Ⅲ级，多形性胶质母细胞瘤为WHO Ⅳ级，美国NCCN2007指引中建议，对于高级别胶质瘤应最大范围切除肿瘤，术后病理为间变性星形细胞瘤者，应予放疗±同期化疗±辅助化疗；而若证实为多形性胶质母细胞瘤者，则应予放疗＋同期化疗＋辅助化疗。关于高级别脑胶质瘤靶区的勾画尚无定论。我们收治一例右侧额叶混合性胶质瘤（部分为间变性星形细胞瘤，部分为多形性胶质母细胞瘤），于外院行肿瘤全切术，术后经多学科讨论后认为应予放疗加替莫唑胺同期化疗及辅助化疗。本文就此病例的放疗靶区勾画及治疗进行讨论。     

宫颈癌调强放射治疗靶区设计的临床研究

目的探讨宫颈癌盆腔调强放射治疗（IMRT）的计划靶区变化对危险器官受照容积百分比的影响。方法常规体外和腔内放射治疗的10例IIb～Ⅲb宫颈癌患者,放疗前行CT扫描并勾画靶区,临床靶区（CTV）包括子宫、宫颈、阴道等原发肿瘤区域及髂总、髂外、髂内、闭孔、骶前淋巴结等区域及其周围组织,计划靶区（PTV）以CTV为基础向外放不同距离形成PTVA、PTVB、PTVC和PTVD,通过DVH图与传统前后两野等中心照射技术对比,了解随着计划靶区的变化,危险器官受照容积的变化。结果膀胱和小肠接受30GY、40GY、45GY剂量的容积采用IMRT技术均小于前后两野照射技术,随着靶区的扩大,受照容积随之增加（P=0．000）。但是,与前后两野对比,IMRT计划并非均能很好地保护直肠,靶区向后扩大≤10mm,直肠受照容积的变化才具有统计学差异（P=0．001）,靶区扩大至15mm时,直肠受照容积无论是低剂量或是高剂量IMRT计划均大于前后两野照射。结论采用IMRT技术代替常规体外放疗能减少膀胱、小肠和直肠受照容积,其优势随着计划靶区的扩大而减少,靶区的精确勾画和定位的高度重复性,以及对内在器官运动的了解,是IMRT的基础。     

放射治疗合并替莫唑胺治疗多形性胶质母细胞瘤的研究

多形性胶质母细胞瘤（glioblastoma multiforme，GBM）是成人脑肿瘤中最常见的一种，恶性度极高。患者手术后容易复发，其中位生存期小于1年，大多数患者在确诊后2年内死亡。目前标准的治疗方法是手术加术后放疗，加或不加辅助化疗。最近的Ⅲ期临床研究结果显示，替莫唑胺与同期放疗加上辅助化疗的疗效要明显优于单纯放疗。中位生存期由单纯放疗组的12．1个月提高到了14．6个月；2年生存率也由单纯放疗的8％提高到26％。从而肯定了替莫唑胺对于新诊断的GBM患者的疗效。     

调强放射治疗靶区勾画培训班

由中华放射肿瘤学分会主办,中国医学科学院肿瘤医院承办"调强放射治疗靶区勾画培训班"定于2008年4月20日至4月24日在北京举办。培训班时间5天,拟授予国家Ⅰ类继续教育学分10分。培训对象为中、高级临床放射肿瘤学医师和物理师,拟招生人数,200-300人。     

脑恶性胶质细胞瘤放射治疗现状

脑恶性脑质细胞瘤约占胶质细胞瘤的８０％－８５％，放射治疗是其主要的治疗手段之一。本文综述了放射治疗的照射剂量、照射容积及超分割放疗、粒子放疗组织间插植放疗、热放疗和放射增敏研究现状。     

多形性胶质母细胞瘤的治疗现状分析

多形性胶质母细胞瘤是颅内原发性恶性肿瘤之一。由于其生物学特征和中枢神经系统在解剖和生理机制方面的复杂性,传统治疗手段包括手术治疗、放射治疗和化学治疗,但是总体效果不佳。近些年来,随着对胶质母细胞瘤分子机制的理解以及在神经影像、手术、放疗技术和新药物方面取得的诸多进步,对于胶质母细胞瘤患者的预后有了一定的改善。本文对胶质母细胞瘤治疗的研究进展作一综述。     

miR-153靶向ZEB2抑制胶质母细胞瘤侵袭与转移

目的:探究miR-153对人胶质母细胞瘤（glioblastoma,GBM）侵袭转移的影响及相关作用机制。方法:利用qRT-PCR检测miR-153在GBM中的表达;将miR-153转染至胶质瘤U251细胞后,应用qRT-PCR 验证转染效率;应用Western blot、Transwell及划痕实验检测U251细胞的上皮间质转化、细胞侵袭及转移能力的变化;应用qRT-PCR及Western blot检测ZEB2的mRNA和蛋白表达;利用质粒转染技术过表达miR-153后,同时过表达ZEB2,再应用Transwell及划痕实验检测U251细胞的侵袭及转移能力的变化。结果:与对照相比,miR-153在GBM中低表达;过表达miR-153显著抑制胶质瘤U251细胞的上皮间质转化、细胞侵袭及转移,并能够抑制U251细胞中ZEB2的蛋白表达;ZEB2过表达有效阻断了miR-153抑制U251细胞侵袭及转移的作用。结论:miR-153能够靶向下调ZEB2,进而抑制胶质瘤U251细胞上皮间质转化及细胞侵袭转移。     

非手术食管癌个体化放疗的靶区勾画进展

个体化放疗的实施取决于两个关键环节,首先是靶区的个体化识别和勾画,另一个是射线的个体化施照。由于放疗设备的更新和精确放疗技术的快速发展,实现射线个体化的精确施照成为可能。近年来,随着功能影像和分子显像等新技术的出现,指明了肿瘤个体化放疗靶区勾画的研究方向。本文对非手术食管癌患者个体化放疗的靶区勾画进行综述,内容涉及应用解剖影像、功能影像、乏氧和分子显像等新技术个体化识别和勾画非手术食管癌的放疗靶区,包括大体肿瘤靶区、临床靶区、计划靶区、生物靶区等。     

直肠癌放疗个体化CTV勾画的研究进展

CTV的准确勾画是实施直肠癌适形放疗的关键步骤,有多个指南曾对直肠癌放疗涉及的亚解剖区及其解剖边界进行了不同的定义。本文拟对直肠癌放射治疗个体化CTV勾画的最新研究进展进行介绍。     

MRI-CT图像融合对脑胶质瘤术后放疗靶区的影响

背景与目的:核磁共振成像(magnetic resonance imaging,MRI)图像对软组织结构具有较高的分辨率,但由于失真和缺乏剂量计算所需要的电子密度而限制了其在脑部肿瘤放射治疗中的应用,而MRI和CT图像融合可解决这一问题。本研究探讨MRI与CT的图像融合精度,及其对脑胶质瘤术后患者放疗临床靶区(clinical target volume,CTV)及危及器官(organs at risk,OARs)体积和中心位置的影响。方法:9例颅内胶质瘤术后患者MRI和CT图像采用标点法进行融合,评价其融合精度,分别采用体积法及几何中心法(center of geometry,COG)研究融合前后临床靶区和危及器官体积和中心的变化,测定病灶MRI-CT融合图像的COG与CT定位图像COG的距离,体积法测定病灶MRI与CT图像融合部分体积(VMRI-CT)占总体积(VMRI CT)的百分比(PMRI-CT)。结果:采用人工标记法进行融合的精度小于1.5mm,完全达到脑部肿瘤的误差要求。融合后各危及器官体积无明显改变(P>0.05);9例患者中8例融合界面勾画的CTV体积比CT定位图像CTV体积减小13.85%～73.59%,1例体积增大10.35%;平均体积比较差异有统计学意义(P<0.05);融合后CTV的中心位置变化最大[(8.74±6.60)mm],其次为双眼[左右眼分别为(5.25±2.38)mm和(5.65±2.56)mm],脑干位置变化最小[(1.83±1.06)mm]。结论:采用人工标记的方法进行图像融合具有较高的融合精度,MRI与CT融合的方法可明显减少脑胶质瘤术后放疗CTV勾画的不确定性。     

直肠癌靶区勾画和计划设计指南

为了规范直肠癌放射治疗的靶区勾画和计划设计,国家癌症中心/国家肿瘤质控中心组织专家在全国多家肿瘤中心进行讨论及投票,选取典型病例制作图谱,并结合国际直肠癌靶区勾画指南/共识的推荐,由专业小组对研讨和调研结果进行汇总,形成本指南。本指南对直肠癌的诊疗概况以及放疗适应证进行了总结;在直肠癌调强放疗规范方面,从直肠癌术前及术后放疗的定位、靶区勾画、正常组织勾画、放疗剂量分割模式、放疗计划制订等方面进行分级推荐,并按照典型病例提供图谱参考,可有效地规范直肠癌放疗流程,为放疗质量控制提供参考。     

食管癌放射治疗临床靶区勾画的相关研究

放疗靶区的界定是影响食管癌精确放射治疗疗效的重要因素.目前食管癌临床靶区(CTV)的勾画范围仍存在较多争议,尚无统一标准.研究提示病理特征、影像学手段及淋巴结转移规律等因素对食管癌CTV勾画可能有指导作用.新的勾画方式如个体化勾画CTV已成为目前的研究热点.     

Treatment for glioblastoma multiforme: current guidelines and Canadian practice

Purpose

Our survey aimed to document variability in the practice patterns of Canadian radiation oncologists treating high-grade brain tumours.

Materials and Methods

A 20-question survey was developed to address various aspects of treatment:

• Guidelines used
• Types of fusion protocols used
• Number of treatment phases
• Margins for volume delineation
• Dose constraints

The survey was sent to Canadian radiation oncologists currently treating the central nervous system (cns) as one of their primary sites.

Results

We attained a 56% response rate from radiation oncologists across Canada treating cns sites. In their practice, 14% of respondents reported following guidelines from the European Organisation for Research and Treatment of Cancer; 32%, from the Radiation Therapy Oncology Group; and 56%, centre-specific guidelines. Single-phase treatment was reported by 60% of clinicians, and two-phase or multi-phase treatments, by 37%. For clinicians treating in single phase, margins from the gross treatment volume (gtv) to the planning treatment volume (ptv) included 0.5 cm (6%), 1 cm (6%), 1.5 cm (25%), 2.0 cm (56%), 2.5 cm (25%), and 3 cm (12.5%), with some respondents selecting more than one standard margin. For clinicians treating in multiple phases, margins from gtv to ptv in phase 2 included 1 cm (10%), 2.0 cm (40%), 2.5 cm (30%), and 3.0 cm (20%). Variability was also observed in dose constraints to critical structures. All respondents trimmed their margins to bony structures.

Conclusions

Our survey shows considerable variation in the current treatment by Canadian radiation oncologists of high-grade brain tumours, especially with respect to guidelines followed, number of phases, and overall volume treated. Further studies are thus required to establish the evidence for optimal radiation volumes and phases, especially as brain tumour treatments evolve in the age of mr imaging and chemotherapy.     

鼻咽癌照射靶体积划定的临床探讨

目的通过分析针对靶体积逐步缩野放疗的临床结果，初步探讨鼻咽癌照射靶体积划定的合理性。方法共81例初治鼻咽癌患者进入研究，按1992年福州分期Ⅰ、Ⅱ、Ⅲ和Ⅳa期分别为4、23、35和19例。43例接受单纯放疗，38例接受放化综合治疗。将照射靶体积划分为鼻咽大体肿瘤体积(GTVnx)、颈部大体肿瘤体积(GTVnd)、临床靶体积1(CTV1)、临床靶体积2(CTV2)，相应计划靶体积分别为PTVnx、PTVnd、PTN1、PTN2。处方剂量PTVnx60-76Gy，PTVnd62-66Gy，PTV160Gy，PTV250—52Gy；按靶体积的剂量要求逐步缩野照射。采用三维治疗计划系统对8例不同期别患者的靶体积受照剂量进行计算，Kaplan—Meier方法计算局部区域无进展生存率、无远地转移生存率和总生存率。结果剂量计算结果显示，各靶体积均获得了所需的剂量覆盖。治疗后鼻咽及颈部肿瘤残留各2例，残留病灶分别位于PTVnx及GIVnd内；鼻咽原发灶及颈部转移灶全消率均为97．5％。中位随访时间15个月，未观察到复发病例；2年局部区域无进展生存率、无远地转移生存率和总生存率分别为100．0％、96．3％、100．0％。结论采用上述靶体积划分方法进行放疗可获得较好局部控制，未观察到靶体积内、外和边缘的复发。但该划分方法的合理性和准确性仍需进一步观察和研究。     

Target volume delineation for partial breast radiotherapy planning: clinical characteristics associated with low interobserver concordance

PURPOSE: To examine variability in target volume delineation for partial breast radiotherapy planning and evaluate characteristics associated with low interobserver concordance. METHODS AND MATERIALS: Thirty patients who underwent planning CT for adjuvant breast radiotherapy formed the study cohort. Using a standardized scale to score seroma clarity and consensus contouring guidelines, three radiation oncologists independently graded seroma clarity and delineated seroma volumes for each case. Seroma geometric center coordinates, maximum diameters in three axes, and volumes were recorded. Conformity index (CI), the ratio of overlapping volume and encompassing delineated volume, was calculated for each case. Cases with CI 相似文献   

Target volume definition for external beam partial breast radiotherapy: Clinical, pathological and technical studies informing current approaches

Partial breast irradiation (PBI) is currently under investigation in several phase III trials and, following a recent consensus statement, its use off-study may increase despite ongoing uncertainty regarding optimal target volume definition. We review the clinical, pathological and technical evidence for target volume definition in external beam partial breast irradiation (EB-PBI). The optimal method of tumour bed (TB) delineation requires X-ray CT imaging of implanted excision cavity wall markers. The definition of clinical target volume (CTV) as TB plus concentric 15 mm margins is based on the anatomical distribution of multifocal and multicentric disease around the primary tumour in mastectomy specimens, and the clinical locations of local tumour relapse (LR) after breast conservation surgery. If the majority of LR originate from foci of residual invasive and/or intraduct disease in the vicinity of the TB after complete microscopic resection, CTV margin logically takes account of the position of primary tumour within the surgical resection specimen. The uncertain significance of independent primary tumours as sources of preventable LR, and of wound healing responses in stimulating LR, increases the difficulties in defining optimal CTV. These uncertainties may resolve after long-term follow-up of current PBI trials. By contrast, a commonly used 10 mm clinical to planning target volume (PTV) margin has a stronger evidence base, although departmental set-up errors need to be confirmed locally. A CTV-PTV margin >10 mm may be required in women with larger breasts and/or large seromas, whilst the role of image-guided radiotherapy with or without TB markers in reducing CTV-PTV margins needs to be explored.