左侧乳腺癌放疗相关心脏毒性的危险因素分析

 放射治疗是乳腺癌的重要治疗手段,由于左乳与心脏位置毗邻,设计照射野时常不能完全避开心脏。乳腺癌放射治疗增加了患缺血性心脏病、心包炎和瓣膜病的风险。年轻、高体重指数（body mass index, BMI）、肿瘤位于中央象限和胸骨旁区域与心脏受到高剂量辐射有关。放疗心脏毒性与放疗技术有很大关系,对于左乳切除术后放疗,多野调强适形放疗（IMRT）能够平衡靶区覆盖和正常组织受量,而左乳保乳术后放疗,采用双弧度容积旋转调强（VMAT）较多野IMRT更具优势。相比全乳照射,加速部分乳腺照射能够显著降低心脏剂量;而对于需要照射区域淋巴结的患者,采用容积旋转调强或螺旋断层放疗在减少心脏受量方面则显示出优势。相比自由呼吸,深吸气屏气放疗能够显著减少心脏和冠状动脉左前降支剂量;尤其是对于胸壁+区域淋巴结（包括内如淋巴结）放疗的患者采用深吸气屏气（deep inspiration breath hold, DIBH）放疗获益更多,而对于保乳术后仍为大乳腺的患者,采用俯卧位能减少心脏毒性。另外,左乳放疗期间同步曲妥珠单抗靶向治疗、芳香化酶抑制剂（aromatase inhibitors, AI）会影响心脏事件的发生。基于上述因素,在给左侧乳腺癌患者制定放疗计划时,应结合患者年龄、BMI、原发肿瘤位置、体型、术后乳腺大小、是否需要区域淋巴结照射,根据现有放疗设备,给予最优的放疗方案,同时减少增加心脏毒性的同步治疗,从而最大程度减少治疗导致的心脏不良反应。     

食道癌患者放疗后脑利钠肽前体变化的研究

目的:心脏的保护是制定食道癌调强放疗计划时需要考虑的重要方面,脑利钠肽前体(N-terminal pro-B-type natriuretic peptide,NT-proBNP)是心脏损伤的重要标志。本研究目的在于评价食道癌患者放疗前后血液中NT-proBNP浓度的改变与心脏的受照射剂量之间的相关关系。方法: 共纳入35例食道癌患者,采用调强技术进行放疗,观察治疗前和治疗后的NT-proBNP变化。对于食道癌患者放疗后NT-proBNP升高的患者予心脏照射剂量的DVH参数进行回归分析。结果:35例行放疗的食道癌患者中,有15例NT-proBNP升高;与照射前相比,放疗后患者血浆中的NT-proBNP(中位100.9ng/L,范围:27.8~386.8ng/L)明显高于放疗前(中位71.5ng/L,范围15.6~120.3ng/L)(P＜0.01)。NT-proBNP升高的15例患者的平均剂量（Dmean）、V35和V55明显高于NT-proBNP未升高的20例患者;其血浆中的NT-proBNP浓度与Dmean(P=0.035)、最大剂量（Dmax）(P=0.045)、V35(P=0.021)和V45(P=0.034)有相关性。结论:食道癌放疗的NT-proBNP浓度明显高于未受照射者,与心脏的Dmean、Dmax、V35和V45相关。     

直肠癌术后辅助性放疗不同照射技术的剂量学研究

目的通过比较常规放疗（CRT）、三维适形放疗（3DCRT）和调强放疗（IMRT）技术照射小肠、膀胱、股骨头体积．剂量关系，探讨直肠癌术后适形放疗理想的计划模式。方法统一规定直肠癌术后辅助性放疗的临床肿瘤体积（CTV）范围，设定PTV为CTV外扩1cm。应用三维治疗计划系统对既往三野照射模式进行剂量学评估。在规定PTV至少达到95％处方剂量前提下，比较具体病例CRT、3DCRT和IMRT技术下小肠、膀胱、股骨头受照射体积．剂量关系。结果（1）既往术后常规治疗模式的优点是膀胱、小肠受照剂量低，缺点是靶区涵盖度差。（2）等剂量线中高剂量区所包括的正常组织器官体积，IMRT〈3DCRT〈新计划的CRT。（3）3DCRT等剂量线的高剂量区所包括小肠、膀胱的体积百分比在3个野与5个野照射技术中基本相同，7个野技术反而使膀胱和小肠的照射剂量增加。IMRT静态调强技术等剂量线高剂量区所包括小肠、膀胱的体积分别以7、9个野最低。结论直肠癌术后辅助放疗若采用常规模式，可造成靶区剂量不足；在采用3DCRT技术时3—5个野技术较为合适，采用IMRT静态调强技术时7个野较为合适。IMRT技术与其他技术相比具有明显剂量学优势，尤其有利于膀胱的保护。     

乳腺癌术后放疗适用深吸气屏气技术患者筛选的研究进展北大核心CSCD

术后放疗引起的心脏不良反应可增加乳腺癌患者特别是左乳腺癌患者心血管不良事件的发生风险,增加的风险与心脏受照射剂量成正比。深吸气屏气(DIBH)技术已被证明能明显降低左乳腺癌患者的心脏剂量,但不同患者从该技术获益程度差异较大,且该技术的实施需要额外的设备、时间及人力等,所以需要提前筛选出适用该技术的患者。本文全面分析了影响DIBH筛选的定位前一般因素,侧重于系统性总结了CT模拟定位图像相关指标,即CT模拟定位时测量心脏接触距离(CCD_(ps))、心胸距离(HCD)、最大心脏宽度(HW_(max))和最大心脏深度(HD_(max))的乘积,及CT模拟定位后测量最大心脏距离、照射野内心脏体积(HVIF)及自由呼吸(FB)与DIBH状态下肺体积差值及心脏体积差值等解剖学指标。这些指标对评估以切线野为主放疗计划是否采用DIBH技术有指导意义。治疗计划系统中快速计划(RP)功能可快速预测DIBH获益程度。本文旨在帮助临床医生筛选出适合采用DIBH技术的患者,使DIBH技术资源能够被合理利用。     

胸部肿瘤放射治疗中心脏照射剂量体积与损伤效应的关系

放射治疗是胸部肿瘤综合治疗的重要组成部分,但其具有明确的致心脏损伤作用。随着放射治疗主流技术的进步,胸部肿瘤放射治疗中心脏照射的剂量体积分布特点发生了转变。放射相关性心脏疾病（radiation-related heart diseases, RRHDs）的发生显著减少,但在以调强放射治疗为主流的精确治疗时代仍不能确保绝对的心脏安全。本文综述了心脏照射剂量体积分布对放射性心脏损伤风险的影响及心脏照射剂量体积评价指标,并对影响心脏照射剂量体积分布的技术因素及放射相关心脏疾病的监测方法进行了探讨。     

食管癌常规放疗与三维适形放疗比较及4种不同设野技术的剂量学研究

目的:比较食管癌常规三野照射(2DRT)和三维适形放疗(3DCRT)两种不同的治疗方式中,以及三维适形照射4种不同设野方法的计划中靶区剂量及正常组织受量。方法:选取10例在我院治疗的食管癌患者的定位CT,由主治医师画出各自靶区,然后设计GTV和PTV。分别按常规三野照射,三维适形照射的4种不同的布野计划分别进行剂量计算。比较下列参数:①靶区剂量选择<95%剂量的体积百分比。②正常组织(选择心脏,左右肺门及双肺)在各计划中最高剂量(Dmax),最低剂量(Dmin),平均剂量(Dmean),90%、80%、30%及10%等剂量线包括的百分体积(V90、V80、V30及V10),脊髓仅选择最高受量。结果:①常规三野照射和适形放疗的比较:PTV各项指标于两者无显著性差异;脊髓有明显差异;左肺受量经t检验,Dmin、Dmean及V30值均有明显的差异。心脏、右肺门及右肺组织的各项参数均无显著性差别。②食管癌三维适形照射4种不同的布野的比较:PTV的剂量覆盖4种计划中无显著性差异。双肺受量t检验显示在V30及V10等指标上计划1、2较3和4有明显减少,提示在双肺低剂量区照射,受累体积方面前2种设野方法较优,类似的趋势也见于左侧肺门的受量上。心脏的受量、右肺门的剂量参数未见明确差异,剂量体积分布以旋转照射略差。结论:①食管癌三野常规照射与三野适形照射比较,三野适形放疗利于保护左肺组织和脊髓。②食管癌三维适形照射4种不同的布野靶区的正常组织受量不同,故布野选择应按患者的具体情况而定。     

左侧乳腺癌保乳术后采用深吸气屏气放疗的心脏剂量学分析

目的 探究左侧乳腺癌保乳术后放疗患者采用深吸气屏气(DIBH)技术对心脏剂量的改善情况,分析可能影响心脏剂量的解剖因素。方法 前瞻性入组 15例左侧乳腺癌保乳术后行全乳放疗患者,符合呼吸控制要求。分别在自由呼吸(FB)和DIBH状态下进行2次模拟CT扫描,在DIBH图像上制定全乳放疗计划。比较FB和DIBH状态下心肺位置和体积变化以及心肺剂量差异,探究FB状态下各解剖因素与心脏剂量的相关性。对计数资料组间行非参数Wilcoxon秩和检验,双变量相关分析采用Pearson法。结果 DIBH与FB状态下心脏体积相似(P=0.773),而双肺体积明显增加(P=0.001)。心脏、冠脉左前降支、左心室、右心室和左肺 Dmean、Dmax和V5—V40均明显降低(P<0.05)。DIBH使肺体积增加越显著,心脏平均剂量下降幅度越大。FB状态下乳腺体积、心肺体积比、乳腺下界与心脏下界距离、最大心脏切缘距离分别与心脏剂量呈线性相关,其中心肺体积比、最大心脏切缘距离与心脏剂量具有独立相关性。结论 左侧乳腺癌保乳术后采用DIBH技术行全乳放疗较FB状态明显降低心肺剂量。肺体积的变化是改善心脏相对解剖位置的基础。心肺体积比、最大心脏切缘距离或许可以作为进行DIBH技术治疗的参考标准。     

深吸气屏气在乳腺癌放射治疗中应用的研究进展

放射治疗是乳腺癌综合治疗的重要环节,但其心肺剂量则易导致放射性心脏病等并发症的发生。因此,如何减少心脏剂量、降低放疗并发症成为乳腺癌精准放疗的研究重点。深吸气屏气是一类呼吸控制方法,其应用于放疗可减少心肺等危及器官的受照剂量,以期减少放射性心脏损伤、改善患者远期预后。本文旨在概述乳腺癌放疗引起的心脏毒性及保护方法,深吸气屏气技术的剂量优势及应用,为临床和科研工作提供思路及方向。     

不同照射方式对纵隔肿瘤受照剂量的影响

目的：探讨不同照射方式，对纵隔肿瘤三维适形照射放疗受照剂量的影响。方法：随机选取2008年1月至2008年8月在云南省放射治疗中心接受三维适形放疗的纵隔肿瘤患者11例，应用三维治疗计划系统，每例均做3个计划，分别为常规倒Y野、纵隔Y形野和交替Y形野三维适形放疗计划，计划采用常规分割方式2Gy／次，总剂量均为70Gy，外放边界1cm。在保证CTV被93％～95％的等剂量线包绕的情形下，用剂量体积直方图（DVH）比较三种照射方法正常组织的受照射剂量的差异。结果：常规倒Y野能有效地降低脊髓和心脏受照剂量，其缺点是肺的V20较高，尤其当肿瘤体积较大时；纵隔Y野能有效地降低肺的V20，其缺点是脊髓和心脏受照剂量偏高；交替Y形野吸取了前两种照射方式的优点，既能有效的降低肺的V20，又能将脊髓控制在其耐受剂量以下。结论：理论上交替Y形野是一种较好的纵隔肿瘤三维适形放疗照射方式。     

乳腺癌放射性心脏损伤的早期识别及影响因素研究进展

乳腺癌术后放疗提高了患者的总体生存率, 但心脏因其解剖位置在放疗期间不可避免地受到照射, 存在放射性心脏损伤的风险。心脏被视为辐射敏感的"高危器官", 其受照剂量应尽可能低。既往研究主要评估心脏整体受照剂量对远期心血管事件的影响, 而最新研究发现, 平均心脏剂量无法准确反映心脏受照程度。近年来放疗后心脏亚临床损伤日益受到重视, 旨在早期识别隐匿性心脏损伤。此外, 特定心脏亚结构剂量与心律失常的关系尚不清楚。本文重点阐述了平均心脏剂量预测放射性心脏损伤的局限性、早期识别心脏损伤的指标及乳腺癌放射性心脏损伤的影响因素, 并关注不同心脏亚结构放射损伤与心律失常的关系, 以期实现乳腺癌患者心脏风险精细化管理, 降低乳腺癌患者的非癌死亡率。     

Doses aux organes à risque en radiothérapie conformationnelle et en radiothérapie en conditions stéréotaxiques : le cœur

Radiation therapy of breast cancer, Hodgkin lymphoma, lung cancer and others thoracic irradiations induce an ionizing radiation dose to the heart. Irradiation of the heart, associated with patient cardiovascular risk and cancer treatment-induced cardiotoxicity, increase cardiovascular mortality. The long survival after breast or Hodgkin lymphoma irradiation requires watching carefully late treatment toxicity. The over-risk of cardiac events is related to the dose received by the heart and the irradiated cardiac volume. The limitation of cardiac irradiation should be a priority in the planning of thoracic irradiations. Practices have to be modified, using modern techniques to approach of the primary objective of radiotherapy which is to optimize the dose to the target volume, sparing healthy tissues, in this case the heart. We have reviewed the literature on cardiac toxicity induced by conformational tridimensional radiation therapy, intensity-modulated radiation therapy or stereotactic body radiation therapy, in order to evaluate the possibilities to limit cardiotoxicity. Finally, we summarise the recommendations on dose constraints to the heart and coronary arteries.     

Cardiac dose sparing and avoidance techniques in breast cancer radiotherapy

Breast cancer radiotherapy represents an essential component in the overall management of both early stage and locally advanced breast cancer. As the number of breast cancer survivors has increased, chronic sequelae of breast cancer radiotherapy become more important. While recently published data suggest a potential for an increase in cardiac events with radiotherapy, these studies do not consider the impact of newer radiotherapy techniques commonly utilized. Therefore, the purpose of this review is to evaluate cardiac dose sparing techniques in breast cancer radiotherapy. Current options for cardiac protection/avoidance include (1) maneuvers that displace the heart from the field such as coordinating the breathing cycle or through prone patient positioning, (2) technological advances such as intensity modulated radiation therapy (IMRT) or proton beam therapy (PBT), and (3) techniques that treat a smaller volume around the lumpectomy cavity such as accelerated partial breast irradiation (APBI), or intraoperative radiotherapy (IORT). While these techniques have shown promise dosimetrically, limited data on late cardiac events exist due to the difficulties of long-term follow up. Future studies are required to validate the efficacy of cardiac dose sparing techniques and may use surrogates for cardiac events such as biomarkers or perfusion imaging.     

Comparison of three different mediastinal radiotherapy techniques in female patients: Impact on heart sparing and dose to the breasts.

BACKGROUND AND PURPOSE: To study different radiotherapy techniques for female patients with mediastinal target volumes. Especially in highly curable diseases such as lymphoma, long-term survivors might develop late cardiac damage and radiation-induced second cancer. PATIENTS AND METHODS: Planning CT scans were obtained in eight cases. We contoured the clinical target volume (three different scenarios with or without lower mediastinum and hili) and organs at risk and compared standard 6MV ap-pa opposed fields to a 3D conformal 4-field technique and a 7-field step-and-shoot IMRT technique and evaluated DVHs for each structure. The planning system was BrainSCAN 5.21 (BrainLAB, Heimstetten, Germany). RESULTS: Target volume coverage did not improve significantly with 4-field or IMRT techniques. However, IMRT resulted in better dose reduction to the heart than the other techniques. The median heart dose (intermediately sized target volume) was 98% (95-100) with ap-pa fields, 56% (52-79) with the 4-field technique, and 39% (36-65) with IMRT, for example (p<0.05). Better heart sparing was achieved at all dose levels down to the 15% isodose. The median maximum dose to the breasts was lowest with IMRT. The breast volume receiving low doses (15% or less), however, was highest with IMRT. There was also a disadvantage in mean lung dose. CONCLUSIONS: IMRT might result in a reduced cardiac complication risk. In younger females, however, this advantage might be offset by the risk of breast cancer. The best technique for a given patient depends on age, comorbidity, and the individual risk estimates for breast cancer and cardiac morbidity, respectively.     

Cardiovascular effects of breast cancer radiotherapy

Cardiac toxicity has been implicated as the primary reason for excess non-breast cancer mortality in early breast cancer radiotherapy studies. Refinements in radiotherapy techniques have allowed for a considerable reduction of this risk in the majority of breast cancer patients. Recent large population-based studies confirmed an increase of cardiovascular death risk in patients irradiated for cancer of the left breast and in individuals exposed to relatively low (hitherto believed to be of no cardiovascular disease risk) doses of radiation, such as atomic bomb survivors or patients treated for various benign conditions. The issue of potential radiation-related cardiac damage may also be assuming a new significance due to the widespread use of other cardiotoxic agents, such as anthracyclines, paclitaxel and trastuzumab. The aim of this review is to summarize and critically analyze the available evidence on the impact of ionizing radiation on the cardiovascular system, with special attention to recent data demonstrating previously unrecognized adverse effects. This review discusses the pathology of radiation-related cardiovascular disease, its clinical presentation, risk factors and methods of assessment, as well as technical developments minimizing cardiac exposure. Epidemiological data are presented on the incidence of radiation-induced heart disease and cardiovascular mortality in various populations of patients irradiated for breast cancer and in individuals exposed to low radiation doses. Additionally, non-cardiac radiation-related vascular morbidity and mortality in breast cancer patients are addressed.     

Improvements in target coverage and reduced spinal cord irradiation using intensity-modulated radiotherapy (IMRT) in patients with carcinoma of the thyroid gland.

BACKGROUND AND PURPOSE: External beam radiotherapy for thyroid carcinoma poses a significant technical challenge as the target volume lies close to or surrounds the spinal cord. The potential of intensity-modulated radiotherapy (IMRT) to improve the dose distributions was investigated. MATERIALS AND METHODS: A planning study was performed on patients with thyroid carcinoma. Plans were generated to irradiate the thyroid bed alone or to treat the thyroid bed and the loco-regional lymph nodes in two phases. Conventional plans with minimal beam shaping were compared to three-dimensional conformal radiotherapy (3DCRT) and inverse-planned IMRT plans to assess target coverage and normal tissue sparing. IMRT techniques were optimized to find the minimum number of equispaced beams required to achieve the clinical benefit and a concomitant boost technique was explored. RESULTS: For the thyroid bed alone and the thyroid bed plus loco-regional lymph nodes, conventional and conformal techniques produced low minimum doses to the planning target volume (PTV) if spinal cord tolerance was respected. 3DCRT reduced the irradiated volume of normal tissue (P=0.01). IMRT plans achieved the goal dose to the PTV (P<0.01) and also reduced the spinal cord maximum dose (P<0.01). IMRT, using a concomitant boost technique, produced better target coverage than a two-phase technique. For both the two-phase and concomitant boost techniques, IMRT plans with seven and five equispaced fields produced similar dose distributions to nine fields, but three fields were significantly worse. CONCLUSIONS: 3DCRT reduced normal tissue irradiation compared to conventional techniques, but did not improve PTV or spinal cord doses. IMRT improved the PTV coverage and reduced the spinal cord dose. A simultaneous integrated boost technique with five equispaced fields produced the best dose distribution. IMRT should reduce the risk of myelopathy or may allow dose escalation in patients with thyroid cancer.     

Irradiation-related ischemic heart disease

An expectation for long-term survival has emerged among several groups of cancer patients treated with therapeutic irradiation (eg, Hodgkin's disease, early stage breast cancer). Therefore, the cardiovascular sequelae of thoracic irradiation have recently come under scrutiny. Animal models have demonstrated that cardiac irradiation can directly damage the myocardial microvasculature and can indirectly damage the coronary macrovasculature when coupled with cholesterol feeding. A clear association between thoracic radiotherapy and ischemic heart disease was observed among older clinical studies using radiotherapeutic techniques that are no longer optimal by today's standards. Such a relationship could not be confirmed in modern studies in which treatment factors (such as dose and volume of heart irradiated) were more carefully controlled.     

A treatment planning study using non-coplanar static fields and coplanar arcs for whole breast radiotherapy of patients with concave geometry.

PURPOSE: A treatment planning study was performed to evaluate the performance of new radiotherapy techniques based on non-coplanar multiple fields or on dynamic conformal arcs for early stage breast treatments. METHODS AND MATERIALS: CT datasets of 7 different patients that were deemed unsuitable for tangential beam treatment due to a large volume of lung in the treatment fields were used as input for the study. Standard tangential field plans and inversely modulated IMRT plans were used as benchmark to evaluate performances of conformal plans with 3 non-coplanar fields (3F-NC), with 2 short dynamic conformal arcs (2-Arc) or hybrid plans with one static conformal field and one dynamic conformal arc (P-Arc). All plans were designed to achieve the higher target coverage and minimum ipsilateral lung involvement depending on the planning technique with a key objective to avoid involvement of the contralateral breast. The following planning objectives were selected. For PTV: D(1%) (maximum significant dose) lower than 110% and D(99%) (minimum significant dose) higher than 90%. For the ipsilateral lung a mean dose lower than 15 Gy and/or a volume receiving more than 20 Gy lower than 22%. For contralateral breast, all techniques but IMRT were set to have no beam impinging this organ at risk, while for IMRT plans were further designed to keep the mean dose lower than 5 Gy and to minimise the volume receiving a dose higher than 70% of the prescribed dose. RESULTS: P-Arc resulted to be on average a better technique, as it provides a PTV dose distribution highly conformal (Conformity index 1.45), homogeneous (D(5%)-D(95%)=15.6%), with adequate coverage (V(90%)=96.4%) and a limited involvement of the ipsilateral lung (MLD approximately 9 Gy, V(5 Gy) approximately 36%, NTCP<2%) when compared to four other treatment techniques. 3F-NC presented similar but slightly worse performances on target: Conformity index 1.57, D(5%)-D(95%)=18.1%, V(90%)=95.7%). 3F-NC on ipsilateral lung resulted as the P-Arc. The tangential approach, the 2-Arc or the IMRT techniques, resulted to be inferior to the previous in either conformality (tangentials), ipsilateral lung sparing (tangentials, 2-Arc and IMRT) and in contralateral or healthy tissue involvement (IMRT). CONCLUSION: For early stage breast cancer when high sparing of lung tissues is required and no involvement of contralateral breast is allowed, the P-Arc or the 3F-NC techniques might be recommended in terms of dosimetric expectations.     

Radiation-related heart toxicity

The radiotherapy of thoracic cancers exposes the heart to late radiation-induced complications. The physiopathological and clinical consequences of heart irradiation have been mostly studied in patients with Hodgkin lymphoma and breast cancer. The main cause of cardiac morbidity is radiation-induced coronaropathy with a relative risk estimated between 2 and 3 in earlier studies. Preexisting factors of cardiovascular risk, including chemotherapy, potentalize the cardiotoxicity of radiotherapy. Conformational radiotherapy, adapting the ballistics and the energy to the delineated volumes while carefully evaluating the dose-volume distribution in the organs at risk, allowed a drastic reduction in cardiac mortality. This toxicity no longer seems to be significant if the cardiac volume has received less than 30 Gy. Nevertheless, the prolonged life expectancy of cancer patients and the expanding use of new cardiotoxic anticancer drugs underline the persistent need to further reduce the dose delivered to the heart. Indeed, 1 Gy added to the mean heart dose would increase the cardiotoxic risk by 4% (IC 95%: 2-6%, P=0.0002). A strengthened collaboration between the radiation oncologist and the cardiologist aims at detecting and treating long-term complications after thoracic radiotherapy.     

Comparison of dose contribution to normal pelvic tissues among conventional, conformal and intensity-modulated radiotherapy techniques in prostate cancer

High-energy external radiotherapy has become one of the most common treatment in localized prostate cancer. We compared the difference of dose distribution, mainly at the 5-30 Gy dose level, in the irradiated pelvic volume among three modalities of radiotherapy for patients with prostate cancer: conventional, conformal and intensity-modulated radiotherapy (IMRT). We selected six patients with prostate cancer treated by conformal radiotherapy at the doses of 46 Gy to PTVN (prostate and seminal vesicles), and 70 Gy to PTV-T (prostate). The conventional technique": an 8-field arrangement was used; the conformal technique 4 fields with a boost through 6 fields. For IMRT, a five-beam arrangement was used. Dose-volume histograms (DVH) were analyzed and compared among the three techniques. The IMRT technique significantly increased the pelvic volume covered by the isodose surfaces below 15 Gy as compared with the conventional and conformal techniques. The mean absolute increase for the pelvic volume included between 5-30 Gy for the IMRT technique, was about 2 900 ml as compared with the conventional technique. However, IMRT significantly reduced the irradiated volume of the rectum in the dose range of 5 to 40 Gy, also significantly reduced the irradiated volume of bladder and femoral heads, and obtained a similar or improved isodose distribution in the PTVs. In addition, the use of IMRT slightly increased the relative dose delivered to the body volume outside the pelvis, as estimated by the use of specific software. A long-term follow-up will be needed to evaluate potential late treatment complications related to the use of IMRT and the low or moderate irradiation dose level obtained in the pelvis and in the whole body.