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1.
目的 探讨子宫颈癌术后调强放疗(IMRT)与三维适形放疗(3DCRT)的临床疗效及安全性。方法 选取我院2012年9月至2013年3月60例宫颈癌术后患者,均制定IMRT和3DCRT两种放疗计划,随机分为IMRT组和3DCRT组进行放疗, IMRT组行5野6MV X射线放疗, 3DCRT组行4野6MV-X射线盒式照射,处方剂量均为95%计划靶区体积(PTV)为45 Gy/25 f/5 W。评价PTV和危及器官(OAR)的剂量分布特点;随访两组OAR的急慢性放射性损伤,计算两组3年生存率。结果IMRT组PTV的适形度指数(CI)、均匀性指数(HI)分别为0.80±0.03、1.10±0.01,3DCRT组分别为0.58±0.19、1.09±0.01,差异有统计学意义(P<0.05);IMRT组膀胱前壁的V10、V20、V30、V40和V45均低于3DCRT组,差异有统计学意义(P<0.05);IMRT组直肠后壁的V20、V30、V40和V45均低于3DCRT组,差异有统计学意义(P<0.05);IMRT组直肠和膀胱的急性和慢性放射性损伤发生率低于3DCRT组,差异有统计学意义(P<0.05)。IMRT组3年生存率为83.3%,3DCRT组为80.0%,差异无统计学意义(P>0.05)。结论 在PTV的CI、HI及保护OAR如膀胱前壁、直肠后壁上,IMRT优于3DCRT。  相似文献   

2.
前列腺癌三维适形和调强放疗的初步结果   总被引:3,自引:0,他引:3  
目的 分析三维适形放疗(3DCRT)和调强放疗(IMRT)前列腺癌的初步疗效和早晚期副反应.方法 36例无远处转移的前列腺癌接受了3DCRT和IMRT,其中35例同时接受内分泌治疗.23例临床靶区包括前列腺或前列腺加精囊,13例先接受盆腔照射然后包括前列腺和精囊.临床靶区的中位剂量为76.0 Gy(52.5~83.0Gy),盆腔预防性照射中位剂量为45.0Gy(40~50Gy).结果 3、5年总生存率分别为91%、84%.3、5年癌症相关生存率均为91%.全组早期胃肠道反应≤2级35例,3级1例,无4级反应;早期泌尿系统副反应≤2级34例,3级2例,无4级反应.全组分别有4例1级和3例2级晚期胃肠道反应,无≥3级晚期胃肠道反应;晚期泌尿系统反应发生率低,6例1级,2级1例,3级1例.结论 应用三维适形放疗和调强放疗技术治疗前列腺癌,高剂量放疗是安全的,早期和晚期副反应可接受,未发现严重晚期副反应.  相似文献   

3.
目的:探讨食管癌三维适形放疗(three-dimensional conformal radiotherapy,3D-CRT)与调强放疗(intensity modulated radiotherapy,IMRT)技术间的剂量参数差异,为临床提供有价值的循证医学证据.方法:计算机检索Cochrane、PubMed、Embase及中国知网(CNKI)、万方数据库中所有比较食管癌三维适形放疗及调强放疗的文章,应用RevMan 5.2软件对所有满足条件的数据进行Meta分析.结果:17篇文献纳入本次研究.食管癌调强放疗与适形放疗比,能显著降低双肺的K0(MD=4.63,95% CI:1.69 ~ 7.56,P<0.01)及K0(MD =4.21,95%CI:1.48 ~6.94,P<0.01),且有更好的适形指数(MD=-0.14,95%CI:-0.2 ~-0.07,P<0.01)及均匀指数(MD =0.04,95%CI:-0.01 ~0.07,P<0.01);双肺V5、V10、心脏V40及脊髓最大受量Dmax两种放疗技术间无统计学差异.结论:食管癌IMRT与3D-CRT比较能明显降低肺的V20及K30,具有更好的靶区适形度.  相似文献   

4.
影像引导非小细胞肺癌适形调强放疗技术进展   总被引:1,自引:0,他引:1  
Xing J  Li JB  Yu JM 《中华肿瘤杂志》2007,29(6):401-404
放射治疗是非小细胞肺癌(non-small cell lung cancer,NSCLC)的主要治疗手段之一,60%以上的NSCLC患者在其治疗的不同时期需要接受放疗。NSCLC放射治疗的目的是最大限度地减少放射性肺损伤,并在确保患者生存质量的前提下,控制局部肿瘤生长、延长患者生存时间或达到治愈,因此,理想的放射治疗是在给予肿瘤高剂量照射的同时,最大限度地保护周围正常的肺组织,这就需要准确  相似文献   

5.
目的:评估三维适形放疗与简化调强放疗两种不同放疗技术在胸中段食管癌放射治疗中的优缺点。方法20例胸中段食管癌患者分别进行3DCRT和sIMRT两种放疗计划设计,处方剂量均为66 Gy/33 f。比较两组计划的靶区与危及器官剂量学参数及加速器跳数( MU)。结果 sIMRT在PTV的剂量覆盖、均一性及适形度均优于3DCRT(P<0.05);3DCRT与sIMRT的双肺V30 Gy及双肺V20 Gy分别为11.61±3.68 vs.10.33±3.02(P=0.010)和23.37±8.38 vs.18.89±4.45(P=0.001)。两组的双肺V5 Gy无显著性差异。3DCRT与sIMRT的MU分别为542.24±76.32和530.80±97.13(P=0.677)。结论与3DCRT相比,sIMRT有较满意的PTV高剂量覆盖及均匀的剂量分布。在危及器官保护方面,sIM-RT的双肺高剂量区范围明显低于3DCRT。两组计划的MU无显著性差异。  相似文献   

6.

BACKGROUND:

Patients with locally recurrent squamous cell cancer of the head and neck (SCCHN) are reported to have a poor prognosis and limited therapeutic options. Optimal management is selectively applied and morbid. Both surgical resection and chemoradiotherapy are reported to result in median survivals of approximately 12 months. Intensity‐modulated radiotherapy (IMRT) is a highly conformal approach for delivering RT. This study reported the experience of the Dana‐Farber Cancer Institute (DFCI) with IMRT‐based chemoradiotherapy with or without surgery for locally recurrent SCCHN.

METHODS:

The current study was a retrospective study of all patients treated at DFCI who were diagnosed with nonmetastatic second primary or recurrent SCCHN and who received reirradiation based on IMRT. The primary endpoint was overall survival (OS), and secondary endpoints were locoregional (LRC) and distant control and acute and chronic toxicity.

RESULTS:

Thirty‐five patients were treated from August 2004 until December 2008. Recurrent disease was treated in the oral cavity (4 patients), larynx/hypopharynx (13 patients), oropharynx (7 patients), nasopharynx (2 patients), and neck (9 patients). The median radiation dose was 60 Gray (Gy), and all patients received concurrent chemotherapy. The median follow‐up was 2.3 years. The 2‐year actuarial OS and LRC rates were 48% and 67%, respectively. Approximately 91% and 46%, respectively, of all patients developed at least 1 acute and late grade 3 toxicity. Four (11%) late deaths occurred in patients with no evidence of disease (2 aspiration events, 1 oropharyngeal hemorrhage, and 1 infectious death).

CONCLUSIONS:

Aggressive chemoradiotherapy with IMRT was found to be feasible and resulted in favorable survival outcomes in comparison with published reports. Acute and late toxicities were substantial. The apparently improved LRC appears to carry a significant risk of developing late complications. Cancer 2010. © 2010 American Cancer Society.  相似文献   

7.
直肠癌五野调强放疗与传统适形放疗剂量学研究   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:研究五野调强技术(IMRT)与三维适形(3DCRT)技术治疗直肠癌肿瘤靶区和危及器官照射剂量的区别。方法:回顾性分析15例直肠癌患者的放疗资料,其中7例为术前放疗,8例为术后放疗。在每位患者的模拟定位CT上分别勾画肿瘤靶区及小肠、膀胱、股骨头等危及器官(OAR),并分别进行3DCRT和IMRT计划设计,要求处方剂量至少覆盖95%的计划靶体积。应用适形指数(CI)和均匀指数(HI)评价肿瘤靶区剂量的分布,应用Dx%(接受高量照射的x%的体积所受到的最低剂量)和平均剂量评价OAR受照射剂量。两个计划剂量分布的差别采用配对t检验比较。结果:在IMRT和3DCRT计划中,CI分别为0.94和0.87(=0.000);HI分别为1.13和1.17(P=0.001);小肠D30%分别为19.67Gy和25.20Gy,D50%分别为15.13Gy和22.20Gy,平均剂量分别为18.81Gy和22.89Gy(均为0.000);膀胱的D30%分别为34.20Gy和44.67Gy,D50%分别为24.80Gy和35.07Gy,平均剂量分别为28.70Gy和35.68Gy(均为0.000);股骨头D5%分别为40.60Gy和40.47Gy(P=0.936),平均剂量分别为30.14Gy和25.57Gy(=0.001)。结论:IMRT在靶区剂量均匀性和适形度方面均优于3DCRT计划,对正常组织的保护也存在明显的优势。  相似文献   

8.
Introduction: The treatment of midline tumors in the head and neck by conventional radiotherapy almost invariably results in xerostomia. This study analyzes whether a simple three-dimensional conformal radiotherapy (3D-CRT) technique with beam intensity modulation (BIM) (using a 10-MV beam of the MM50 Racetrack Microtron) can spare parotid and submandibular glands without compromising the dose distribution in the planning target volume (PTV).

Methods: For 15 T2 tumors of the tonsillar fossa with extension into the soft palate (To) and 15 T3 tumors of the supraglottic larynx (SgL), conventional treatment plans, consisting of lateral parallel opposed beams, were used for irradiation of both the primary tumor (70 Gy) and the elective neck regions (46 Gy). Separately, for each tumor a 3-D conformal treatment plan was developed using the 3-D computer planning system, CadPlan, and Optimize, a noncommercial program to compute optimal beam profiles. Beam angles were selected with the intention of optimal sparing of the salivary glands. The intensity of the beams was then modulated to achieve a homogeneous dose distribution in the target for the given 3D-CRT techniques. The dose distributions, dose–volume histograms (DVHs) of target and salivary glands, tumor control probabilities (TCPs), salivary gland volumes absorbing a biologically equivalent dose of greater than 40 or 50 Gy, and normal tissue complication probabilities (NTCPs) of each treatment plan were computed. The parameters of the 3D-CRT plans were compared with those of the conventional plans.

Results: In comparison with the conventional technique, the dose homogeneity in the target volume was improved by the conformal technique for both tumor sites. In addition, for the SgL conformal technique, the average volumes of the parotid glands absorbing a BED of greater than 40 Gy (V40) decreased by 23%, and of the submandibular glands by 7% (V40) and 6% (V50). Consequently, the average NTCPs for the parotid and submandibular glands were reduced by 7% and 6%, respectively. For the To conformal techniques, the V40 of the parotid glands was decreased on average by 31%, resulting in an average reduction of the NTCP by 49%. Both the average V50 and the NTCP of the submandibular glands were decreased by 7%.

Conclusion: For primary tumors of the oropharynx, the parotid glands could be spared to a considerable degree with the 3D-CRT technique. However, particularly the ipsilateral submandibular gland could not be spared. For primary tumors of the larynx, the 3D-CRT technique allows sparing of all salivary glands to a considerable and probably clinically relevant degree. Moreover, the conformal techniques resulted in an increased dose homogeneity in the PTV of both tumor sites.  相似文献   


9.
10.
Intensity-modulated radiotherapy (IMRT) is a modern treatment technique that allows one to shape the dose to the target volume and to reduce the dose delivered to healthy tissue. Over the last decade, IMRT has been implemented for head and neck cancer treatment, with the aim of reducing the dose delivered to the parotid glands and improving the dose coverage of complex target volumes located close to critical structures. The potential benefits of IMRT in terms of salivary function preservation and better local control have contributed to the rapid diffusion of this new technology. However, it should not be overlooked that IMRT is a novel treatment technique and that its clinical application represents a paradigm shift in the practice of radiation oncology. The purpose of this article is to review the clinical experience with IMRT for head and neck cancer treatment and to discuss some important issues related to its implementation.  相似文献   

11.
目的:探讨直肠癌术前三维适形放疗(3D-CRT)和五野调强放射治疗(5F-IMRT)计划的剂量学特点,及其术前放疗较佳的放疗技术.方法:对27例拟行术前放疗的直肠癌患者进行3D-CRT和IMRT 2套治疗计划设计,比较2种放疗计划的靶区剂量学特点以及小肠、膀胱和双侧股骨头等正常组织的受照射剂量及体积.结果:5F-IMRT计划中适形指数(CI)为(0.805±0.050),大于3D-CRT(0.698±0.060),P<0.001;2种计划的GTV均匀指数(HI)值均非常接近1,差异无统计学意义;5F-IMRT计划中HICTV和HIPTV值均分别小于3D-CRT计划,P<0.05.5F-IMRT计划中小肠D5、Dmin和Dmax与3D-CRT相应参数差异无统计学意义,但Dmean低于3D-CRT,P<0.05;5F-IMRT计划中小肠V30高于3D-CRT,而V50则前者低于后者,差距也有统计学意义,P=0.041.类似的结果也见于膀胱.5F-IMRT计划中左、右股骨头Dmin和Dmax均低于3D-CRT,V40也明显小于3D-CRT,P<0.05.结论:直肠癌术前放疗5F-IMRT计划剂量分布适形性及均匀性明显优于3D-CRT,且能更好地保护直肠周边邻近的正常组织器官.  相似文献   

12.
The aim of this study is to investigate to what extent IMRT can decrease the dose to the organs at risk in bladder cancer treatment compared with conformal treatment while making separate treatment plans for the elective field and the boost. Special attention is paid to sparing small intestines. Twenty patients who were treated with the field-in-field technique (FiF) were re-planned with intensity modulated radiotherapy (IMRT) using five and seven beams, respectively. Separate treatment plans were made for the elective field (including the pelvic lymph nodes) and the boost, which enables position correction for bone and tumour separately. The prescribed dose was 40 Gy to the elective field and 55 or 60 Gy to the planning target volume (PTV). For bladder and rectum, V45Gy and V55Gy were compared, and for small intestines, V25Gy and V40Gy. The dose distribution with IMRT conformed better to the shape of the target. There was no significant difference between the techniques in dose to the healthy bladder. The median V40Gy of the small intestines decreased from 114 to 66 cc (P = 0.001) with five beam IMRT, and to 55 cc (P = 0.001) with seven beam IMRT compared with FiF. V45Gy for rectum decreased from 34.2% to 17.5% (P = 0.004) for both five and seven beam plans, while V55Gy for rectum remained the same. With IMRT, a statistically significant dose decrease to the small intestines can be achieved while covering both tumour and elective PTV adequately.  相似文献   

13.
BACKGROUND AND PURPOSE: Predictive factors for local-regional (LR) failures after parotid-sparing, Intensity modulated (IMRT) or 3D conformal radiotherapy for head and neck (HN) cancers were assessed. PATIENTS AND METHODS: One hundred and fifty-eight patients with mostly stages III-IV HN squamous cell carcinoma underwent curative bilateral neck irradiation aimed at sparing the parotid glands. Patient, tumor, and treatment factors were analyzed as predictive factors for LR failure. RESULTS: Twenty-three patients had LR recurrence (19 in-field and four marginal). No differences were found in the doses delivered to the PTVs of patients with or without in-field recurrences. In univariate analysis, tumor site was highly predictive for LR failure in both postoperative and definitive RT patients. In postoperative RT patients, pathologic tumor size, margin status, extracapsular extension (ECE) and number of lymph node metastases, were also significantly predictive. Multivariate analysis showed tumor site (oropharynx vs. other sites) to be a significant predictor in all patients, and involved margins and number of involved lymph nodes in postoperative patients. CONCLUSIONS: Clinical rather than dosimetric factors predicted for LR failures in this series, and were similar to those reported following standard RT. These factors may aid in the selection of patients for studies of treatment intensification using IMRT.  相似文献   

14.
The aim of this paper is to analyze the positional accuracy, kinetic properties of the dynamic multileaf collimator (MLC) and dosimetric evaluation of fractional dose delivery for the intensity modulated radiotherapy (IMRT) for step and shoot and sliding window (dynamic) techniques of Varian multileaf collimator millennium 80. Various quality assurance tests such as accuracy in leaf positioning and speed, stability of dynamic MLC output, inter and intra leaf transmission, dosimetric leaf separation and multiple carriage field verification were performed. Evaluation of standard field patterns as pyramid, peaks, wedge, chair, garden fence test, picket fence test and sweeping gap output was done. Patient dose quality assurance procedure consists of an absolute dose measurement for all fields at 5 cm depth on solid water phantom using 0.6 cc water proof ion chamber and relative dose verification using Kodak EDR-2 films for all treatment fields along transverse and coronal direction using IMRT phantom. The relative dose verification was performed using Omni Pro IMRT film verification software. The tests performed showed acceptable results for commissioning the millennium 80 MLC and Clinac DHX for dynamic and step and shoot IMRT treatments.  相似文献   

15.
目的 前列腺大分割照射与盆腔常规分割预防照射相结合的同步加量放疗可提高前列腺癌临床疗效,本研究比较固定野动态调强(dynamic intensity modulated radiotherapy,dIMRT)与快速旋转调强(RapidArc)在前列腺癌同步加量放疗中的剂量分布、治疗效率和执行精度的差异,为临床应用提供参考.方法 选取2013-01-04-2013-12-31在中山大学肿瘤防治中心行放疗的10例前列腺癌高危风险患者,靶区包括前列腺、精囊和盆腔淋巴结.以相同的剂量目标和优化参数分别设计9野dIMRT、单弧和双弧RapidArc同步加量治疗计划,分别用9F、1ARC和2ARC表示.比较分析3种计划的靶区剂量学特点,直肠、膀胱、小肠和双侧股骨头等危及器官的受照剂量及体积,机器跳数,治疗时间以及剂量验证通过率.结果 对于PTV1,9F的D2%为(69.37±0.89) Gy,D50%为(66.92±0.63) Gy,HI为0.09±0.02,CI为0.83±0.05;1ARC的D2%为(71.13±1.21) Gy,D50%为(68.50±0.76) Gy,HI为0.12±0.02,CI为0.74±0.07;9F均优于1ARC,差异均有统计学意义,P<0.05;9F与2ARC的各参数差异均无统计学意义,P>0.05.对于PTV2,9F的V5%为(99.45±0.78)%,优于1ARC的(99.35±1.28)%,差异有统计学意义,P<0.05;9F与2ARC各参数的差异均无统计学意义,P>0.05.对于膀胱Dmean,3组计划差异无统计学意义,P>0.05;对于直肠V67.5Gy,9F与2ARC的差异无统计学意义,P>0.05;对于左右股骨头Dmean,1ARC和2ARC低于9F,差异有统计学意义,P<0.05;各OAR其余评价指标9F均低于1ARC和2ARC,差异均有统计学意义,P<0.05.1ARC和2ARC相比于9F机器跳数平均减少了70.0%和67.2%,治疗时间平均缩短了81.7%和61.0%.9F、1ARC和2ARC的3%/3 mm标准的γ通过率分别为97.8%、98.9%和99.4%,差异均具有统计学意义,P<0.05.结论 相比于dIMRT,RapidArc可显著提高治疗效率,其双弧计划具有相仿的靶区覆盖,但对膀胱、直肠和小肠的保护更差,dIMRT更适用于前列腺癌同步加量放射治疗.  相似文献   

16.
Eighty-three patients with oropharyngeal, hypopharyngeal or laryngeal cancer were treated with concomitant cisplatin 40 mg/m2 once a week during the radiotherapy and IMRT up to a total dose of 70 Gy. The 2-year rate of local control, overall survival and disease specific survival were 84%, 82% and 89%, respectively. The corresponding 5-year Kaplan-Meier estimates were 79%, 69% and 76%.  相似文献   

17.
18.
Intensity‐modulated radiotherapy (IMRT) has been available at Peter MaCallum Cancer Centre (PMCC) since November 2000. The present report illustrates two cases of our early experience with IMRT. Case 1 is a 66‐year‐old man with a T1N2M0 nasopharyngeal carcinoma treated with chemo‐radiotherapy using parotid‐sparing IMRT. Fourteen months following treatment he remains in complete remission, with salivary function assessed using a xerostomia‐specific quality of life questionnaire, having returned to near pretreatment levels by 12 months. Case 2 is a 70‐year‐old man with a T4N0M0 base of tongue squamous cell carcinoma treated with chemo‐radiotherapy after refusing radical surgery. He had received subtotal nodal irradiation to 36 Gy in 1994 for Hodgkins disease stage IIA. A radical dose was still achievable despite previous irradiation without exceeding unacceptable spinal cord dose with IMRT. He remains in complete remission 14 months from his initial presentation without evidence of neurological toxicity. Intensity‐modulated radiotherapy allows sparing of critical normal structures in the head and neck without compromising dose to the tumour. It is, therefore, desirable for several clinical applications and essential in some, if unacceptable compromises are not to be made.  相似文献   

19.

Background and purpose

To evaluate the feasibility of using a photon MLC (xMLC) for modulated electron radiotherapy treatment (MERT) as an alternative to conventional post-mastectomy chest wall (CW) irradiation. A Monte Carlo (MC) based planning system was developed to overcome the inaccuracy of the ‘pencil beam’ algorithm. MC techniques are known to accurately calculate the dose distributions of electron beams, allowing the explicit simulation of electron interactions within the MLC.

Materials and methods

Four real clinical CW cases were planned using MERT which were compared with the conventional electron treatments based on blocks and by a straightforward approach using the MLC, and not the blocks (as an intermediate step to MERT) to shape the same segments with SSD between 60 and 70 cm depending on PTV size. MC calculations were verified with an array of ionization chambers and radiochromic films in a solid water phantom.

Results

Tests based on gamma analysis between MC dose distributions and radiochromic film measurements showed an excellent agreement. Differences in the absolute dose measured with a plane-parallel chamber at a reference point were below 3% for all cases. MERT solution showed a better PTV coverage and a significant reduction of the doses to the organs at risk (OARs).

Conclusion

MERT can effectively improve the current electron treatments by obtaining a better PTV coverage and sparing healthy tissues. More directly, block-shaped treatments could be replaced by MLC-shaped non-modulated segments providing similar results.  相似文献   

20.
目的:探讨三维适形(3D-CRT)与调强放疗(IMRT)治疗T4期食管癌的疗效及预后因素.方法:170例T4期食管癌接受3D-CRT或IMRT,放疗剂量DT 54~70 Gy.采用前程常规后程3D-CRT者35例,全程3D-CRT者88例,IMRT者47例.SPSS 11.5软件进行预后分析.结果:全组放疗后食管造影评价CR 52例,PR 105例,NR 13例,总有效率(CR+PR)为92.4%(157/170);1、3年总生存率分别为61.2%和25.2%,中位生存期15.4个月.后程3D-CRT、全程3D-CRT和IMRT组1、3年生存率(x2=0.89,P=0.641)和局部无复发生存率(x2=0.24,P=0.886)差异均无统计学意义.分层分析结果显示,仅有淋巴结转移者后程3D-CRT与IMRT(x2=4.91,P=0.027)、胸中下段癌后程3D-CRT与全程3D-CRT(x2 =4.25,P=0.039)以及后程3D-CRT与IMRT(x2=4.35,P=0.033),亚组间1、3年生存率差异有统计学意义;其余各因素3组间比较生存率差异均无统计学意义,P>0.05.全组预后COX分析结果显示,仅食管原发肿瘤部位、淋巴结转移和近期疗效为独立预后因素.结论:IMRT与3D-CRT治疗T4食管癌,生存优势不明显;原发肿瘤部位、淋巴结转移及近期疗效影响T4食管癌预后,结果有待进一步前瞻性研究证实.  相似文献   

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