Cancer du poumon et irradiation ganglionnaire prophylactique : un débat clos ?

Lung cancer treatment is a heavy workload for radiation oncologist and that field showed many evolutions over the last two decades. The issue about target volume was raised when treatment delivery became more precise with the development of three-dimensional conformal radiotherapy. Initially based upon surgical series, numerous retrospective and prospective studies aimed to evaluate the risk of elective nodal failure of involved-field radiotherapy compared to standard large field elective nodal irradiation. In every setting, locally advanced non-small cell lung cancer, localized non-small cell lung cancer, localized small cell lung cancer, exclusive chemoradiation or postoperative radiotherapy, most of the studies showed no significant difference between involved-field radiotherapy or elective nodal irradiation with elective nodal failure rate under 5% at 2 years, provided staging had been done with modern imaging and diagnostic techniques (positron emission tomography scan, endoscopy, etc.). Moreover, if reducing irradiated volumes are safe regarding recurrences, involved-field radiotherapy allowed dose escalation while reducing acute and late oesophageal, cardiac and pulmonary toxicities. Consequently, major clinical trials involving radiotherapy initiated in the last two decades and international clinical guidelines recommended omission of elective nodal irradiation in favour of in-field radiotherapy.     

Motion Management for Radical Radiotherapy in Non-small Cell Lung Cancer

Intrafraction tumour motion is an issue that is of increased interest in the era of image-guided radiotherapy. It is particularly relevant for non-small cell lung cancer, for which a number of recent developments are in use to aid with motion management in the delivery of radical radiotherapy. The ability to deliver hypofractionated ablative doses, such as in stereotactic radiotherapy, has been aided by improvements in the ability to analyse tumour motion and amend treatment delivery. In addition, accounting for tumour motion can enable dose escalation to occur by reducing the normal tissue being irradiated by virtue of a reduction in target volumes. Motion management for lung tumours incorporates five key components: imaging, breath-hold techniques, abdominal compression, respiratory tracking and respiratory gating. These will be described, together with the relevant benefits and associated complexities. Many studies have described improved dosimetric coverage and reduced normal tissue complication probability rates when using motion management techniques. Despite the widespread uptake of many of these techniques, there is a paucity of literature reporting improved outcome in overall survival and local control for patients whenever motion management techniques are used. This overview will review the extent of lung tumour motion, ways in which motion is detected and summarise the key methods used in motion management.     

PET and PET/CT in radiation treatment planning for prostate cancer

Molecular imaging by means of PET provides a method to study the metabolic activity of tumors in vivo. ¹⁸F- or ¹¹C-choline and occasionally ¹⁸F- or ¹¹C-acetate, are used as tracers for prostate cancer, reflecting the phospholipid metabolism. The hybrid technology PET/computed tomography significantly reduces image fusion mismatch. The role of molecular imaging is increasing in radiation treatment planning for prostate cancer. Local prostate cancer recurrence after primary radiation treatment usually originates at the location of the primary tumor. Focusing the dose escalation on the actual tumor is an option to increase tumor control without increasing toxicity. Image-guided radiotherapy and intensity-modulated radiotherapy are prerequisite technologies for applying the simultaneous boost concept. Clinical results are needed in the near future to support the effectiveness of the concept.     

Progress in the management of limited‐stage small cell lung cancer

Approximately 15% of lung cancer cases are of the small cell subtype, but this variant is highly aggressive and is often diagnosed at advanced stages. Outcomes after current treatment regimens have been poor, with 5‐year survival rates as low as 25% for patients with limited‐stage disease. Advances in therapy for small cell lung cancer have included the development of more effective chemotherapeutic agents and radiation techniques. For example, hyperfractionated radiotherapy given early in the course of the disease can reduce local recurrence and extend survival. Other technologic advances in radiation planning and delivery such as intensity‐modulated radiotherapy, image‐guided adaptive radiotherapy, and 4‐dimensional computed tomography/positron emission tomography have facilitated the design of treatment volumes that closely conform to the shape of the tumor, which allows higher radiation doses to be given while minimizing radiation‐induced toxicity to adjacent structures. Future improvements in outcomes will require clarifying the molecular basis for this disease. Cancer 2014;120:790–798 . © 2013 American Cancer Society.     

Image-guided Adaptive Radiotherapy for Bladder Cancer

Technological advancement has facilitated patient-specific radiotherapy in bladder cancer. This has been made possible by developments in image-guided radiotherapy (IGRT). Particularly transformative has been the integration of volumetric imaging into the workflow. The ability to visualise the bladder target using cone beam computed tomography and magnetic resonance imaging initially assisted with determining the magnitude of inter- and intra-fraction target change. It has led to greater confidence in ascertaining true anatomy at each fraction. The increased certainty of dose delivered to the bladder has permitted the safe reduction of planning target volume margins. IGRT has therefore improved target coverage with a reduction in integral dose to the surrounding tissue. Use of IGRT to feed back into plan and dose delivery optimisation according to the anatomy of the day has enabled adaptive radiotherapy bladder solutions. Here we undertake a review of the stepwise developments underpinning IGRT and adaptive radiotherapy strategies for external beam bladder cancer radiotherapy. We present the evidence in accordance with the framework for systematic clinical evaluation of technical innovations in radiation oncology (R-IDEAL).     

Adaptive radiotherapy for head and neck cancers: Fact or fallacy to improve therapeutic ratio?

Modern standards of precision radiotherapy, primarily driven by the technological advances of intensity modulation and image guidance, have led to increased versatility in radiotherapy planning and delivery. The ability to shape doses around critical normal organs, while simultaneously “painting” boost doses to the tumor have translated to substantial therapeutic gains in head and neck cancer patients. Recently, dose adaptation (or adaptive radiotherapy) has been proposed as a novel concept to enhance the therapeutic ratio of head and neck radiotherapy, facilitated in part by the onset of molecular and functional imaging. These contemporary imaging techniques have enabled visualisation of the spatial molecular architecture of the tumor. Daily cone-beam imaging, besides improving treatment accuracy, offers another unique angle to explore radiomics – a novel high throughput feature extraction and selection workflow, for adapting radiotherapy based on real-time tumor changes. Here, we review the existing evidence of molecular and functional imaging in head and neck cancers, as well as the current application of adaptive radiotherapy in the treatment of this tumor type. We propose that adaptive radiotherapy can be further exploited through a systematic application of molecular and functional imaging, including radiomics, at the different phases of planning and treatment.     

Accelerated partial-breast intensity-modulated radiotherapy results in improved dose distribution when compared with three-dimensional treatment-planning techniques

PURPOSE: To compare dose distribution and normal tissue sparing in partial-breast treatment using three-dimensional conformal radiotherapy (3D-CRT) vs. intensity-modulated radiotherapy (IMRT). METHODS AND MATERIALS: Sixty-three patients with Tis-1N0M0 breast cancer were treated on a Phase II prospective accelerated partial-breast IMRT protocol at two facilities between April 2004 and January 2006. Fifty-six patients had data sets sufficient to adequately contour all structures. These cases were subsequently replanned with 3D-CRT techniques using the same contours, to compare the dose distribution patterns of 3D-CRT vs. IMRT. RESULTS: The average planning target volume (PTV) to ipsilateral breast (IB) ratio was 24% (range, 7-58%). The average volume of IB receiving 25%, 50%, 75%, and 100% of the prescribed dose was 4.0%, 5.0%, 5.5%, and 10.5% less with IMRT than with 3D (p < 0.01). The dose reduction to normal breast was further improved in the subset of patients whose PTV to IB ratio was >25%, and in patients with contoured breast volume <750 cm(3). No difference was detected in delivery to the lumpectomy cavity or clinical target volume. The PTV volume receiving 95% of the dose was higher in the 3D conformal plans (p < 0.01), but no significant difference was observed in the PTV volume receiving 90% (p = 0.17). The irradiated heart and lung volumes were small with both techniques but also favored IMRT. CONCLUSIONS: In T1N0 patients treated with external beam partial-breast radiotherapy, IMRT improves normal tissue sparing in the ipsilateral breast compared with 3DRT, without compromising dose delivery to the lumpectomy cavity and clinical target volume.     

Effect and mechanism of 125I radioactive particles interposed radiotherapy between organizations on lung cancer

Objective

The aim of this study was to evaluate effect and mechanism of ¹²⁵I radioactive particles interposed radiotherapy between organizations on lung cancer.

Methods

Fourteen cases of patients diagnosed with non-small cell lung cancer (NSCLC), the use of the B-, CT-guided, according to preoperative imaging and treatment planning system (TPS) program for radioactive particles interposed ¹²⁵I interstitial radiotherapy.

Results

All patients were successfully ¹²⁵I interstitial radioactive particles interposed radiotherapy. Postoperative local complete tumor remission in 9 cases, partial remission in 5 cases, the efficiency of 100%. No case of serious complications. After 3 to 4 weeks of chemotherapy after 11 cases. 4 cases of lung cancer with bone metastases, pain completely disappeared after treatment. Up to now, five cases have died due to tumor progression, survival time of 12 to 16 months. Nine cases still under follow-up observation and treatment.

Conclusion

¹²⁵I radioactive particles interposed radiotherapy between organizations of lung cancer, simple operation, trauma, fewer complications, conformal high, high local tumor dose, efficacy, and is a supplement of modern radiotherapy techniques for the treatment of lung cancer provides a comprehensive line of the method of effective.     

Image-guided Radiotherapy to Manage Respiratory Motion: Lung and Liver

Organ motion as a result of respiratory and cardiac motion poses significant challenges for the accurate delivery of radiotherapy to both the thorax and the upper abdomen. Modern imaging techniques during radiotherapy simulation and delivery now permit better quantification of organ motion, which in turn reduces tumour and organ at risk position uncertainty. These imaging advances, coupled with respiratory correlated radiotherapy delivery techniques, have led to the development of a range of approaches to manage respiratory motion. This review summarises the key strategies of image-guided respiratory motion management with a focus on lung and liver radiotherapy.     

PET/CT in radiation oncology

The progressive integration of positron emission tomography/computed tomography (PET/CT) imaging in radiation therapy has its rationale in the biological intertumoral and intratumoral heterogeneity of malignant lesions that require the individual adjustment of radiation dose to obtain an effective local tumor control in cancer patients. PET/CT provides information on the biological features of tumor lesions such as metabolism, hypoxia, and proliferation that can identify radioresistant regions and be exploited to optimize treatment plans. Here, we provide an overview of the basic principles of PET-based target volume selection and definition using ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) and then we focus on the emerging strategies of dose painting and adaptive radiotherapy using different tracers. Previous studies provided consistent evidence that integration of ¹⁸F-FDG PET/CT in radiotherapy planning improves delineation of target volumes and reduces the uncertainties and variabilities of anatomical delineation of tumor sites. PET-based dose painting and adaptive radiotherapy are feasible strategies although their clinical implementation is highly demanding and requires strong technical, computational, and logistic efforts. Further prospective clinical trials evaluating local tumor control, survival, and toxicity of these emerging strategies will promote the full integration of PET/CT in radiation oncology.     

Nouvelles techniques et bénéfices attendus pour la radiothérapie du cancer du poumon

Radiotherapy is used for inoperable lung cancers, sometimes in association with chemotherapy. Outcomes of conventional radiotherapy are disappointing. New techniques improve adaptation to tumour volume, decrease normal tissue irradiation and lead to increasing tumour dose with the opportunity for improved survival. With intensity-modulated radiation therapy, isodoses can conform to complex volumes. It is widely used and seems to be indicated in locally advanced stages. Its dosimetric improvements have been demonstrated but outcomes are still heterogeneous. Stereotactic radiotherapy allows treatment of small volumes with many narrow beams. Dedicated devices or appropriate equipment on classical devices are needed. In early stages, its efficacy is comparable to surgery with an acceptable toxicity. Endobronchial brachytherapy could be used for early stages with specific criteria. Hadrontherapy is still experimental regarding lung cancer. Hadrons have physical properties leading to very accurate dose distribution. In the rare published studies, toxicities are roughly lower than others techniques but for early stages its effectiveness is not better than stereotactic radiotherapy. These techniques are optimized by metabolic imaging which precisely defines the target volume and assesses the therapeutic response; image-guided radiation therapy which allows a more accurate patient set up and by respiratory tracking or gating which takes account of tumour respiratory motions.     

Radiotherapy in muscle-invasive bladder cancer: the latest research progress and clinical application

The role of radiotherapy (RT) in the management of urinary bladder cancer has undergone several alterations along the last decades. Recently, many protocols have been developed supporting the use of multi-modality therapy, and the concept of organ preservation began to be reconsidered. Advances in radiotherapy planning, verification, and delivery provide a method to optimize radiotherapy for bladder cancer and overcome difficulties which have previously limited the success of this treatment. They offer the opportunity to enhance the therapeutic ratio by reducing the volume of normal tissue irradiated and by increasing radiation dose or using more intensive fractionation and synchronous chemotherapy regimes. These techniques have a large potential to improve the therapeutic outcome of bladder cancer. In the near future, it should be possible to offer selected patients with muscle-invasive bladder cancer an organ-sparing, yet effective combined-modality treatment. In this review, we aim to present the role of radiotherapy in the management of muscle invasive bladder cancer. Alternative methods of improving treatment accuracy such as helical tomotherapy, adaptive radiotherapy and radiochemotherapy are also discussed.     

New radiotherapy approaches in locally advanced non-small cell lung cancer

Radiotherapy plays a major role in the treatment of patients with locally advanced non-small cell lung cancer (NSCLC), particularly since most patients are not suitable for surgery due to the extent of their disease, advanced age and multiple co-morbidities. Despite advances in local and systemic therapies local control and survival remain poor and there is a sense that a therapeutic plateau has been reached with conventional approaches. Strategies for the intensification of radiotherapy such as dose escalation have shown encouraging results in phase I–II trials, but the outcome of the phase III Radiation Therapy Oncology Group 0617 trial was surprisingly disappointing. Hyperfractionated and/or accelerated fractionating schedules have demonstrated superior survival compared to conventional fractionation at the expense of greater oesophageal toxicity. Modern radiotherapy techniques such as the integration of 4-dimensional computed tomography for planning, intensity modulated radiotherapy and image-guided radiotherapy have substantially enhanced the accuracy of the radiotherapy delivery through improved target conformality and incorporation of tumour respiratory motion. A number of studies are evaluating personalised radiation treatment including the concept of isotoxic radiotherapy and the boosting of the primary tumour based on functional imaging. Proton beam therapy is currently under investigation in locally advanced NSCLC. These approaches, either alone or in combination could potentially allow for further dose escalation and improvement of the therapeutic ratio and survival for patients with NSCLC.     

肺癌患者放射性肺炎诊治回顾性分析

目的:回顾性分析肺癌患者接受胸部放疗后并发放射性肺炎的发生率,了解其发生的相关因素及诊治情况。方法:选取接受胸部放疗的Ⅱ～Ⅳ期肺癌患者968例,研究照射剂量、面积等14个因素对放射性肺炎发生的影响。应用SPSS 13.0进行χ2检验的单因素分析。结果:113例患者均发生不同程度的放射性肺炎,发生率11.7%(113/968)。单因素分析显示,放疗剂量、射野面积、辐照体积V30及合并胸腔积液、肺部感染、有肺慢性疾病病史是放射性肺炎的主要影响因素;肿瘤病理类型、临床分期、性别、合并化疗、糖尿病与放射性肺炎无关。放射性肺炎的治疗除吸氧、支气管扩张剂等一般处理外,抗生素加激素治疗是关键。结论:照射野面积大和剂量高的患者放射性肺炎的发生率明显增高,在肺癌放疗中正确设计放疗靶区,全面了解患者的肺部并发症,可明显减少放射性肺炎的发生机会。     

FeNO预测肺癌患者放射性肺炎的临床价值

目的:观察肺癌患者放疗后一氧化氮分数（FeNO）的增加能否提示放射性肺损伤。方法:本研究中，我们评估了FeNO变化与放疗后呼吸症状、CT扫描改变和剂量体积直方图（DVH）参数之间的关系。测量65例肺癌患者放疗前及放疗后4、5、6、10周和4、7.5月的FeNO。结果:在放疗后，11名肺癌患者（17%）自述有明显的呼吸道症状，21名（32%）患者有超过1/3的被照射肺区表现出放射性肺炎样图像。13名患者（20%）的FeNO增加超过10 ppb。以FeNO增加超过10 ppb为标准诊断放疗相关呼吸症状的灵敏度和特异性分别为18%和83%。FeNO变化与放疗后DVH参数或CT扫描改变之间无显著相关性。3名患者（5%）在第4、5周持续表现出异常高水平的FeNO（2或3倍，高达55 ppb），随后出现了显著的呼吸症状和/或放射性肺炎图像。结论:放疗期间的连续FeNO监测预测肺癌患者放射性肺炎症状或图像的能力较差。然而，三名患者表现出的特定模式值得研究。     

立体定向放射治疗肺癌脑转移疗效分析

目的探讨不同放射治疗方法对肺癌脑转移的疗效.方法176例由病理学证实的肺癌脑转移患者分为4组:单纯全脑放疗(WBRT)组、全脑放疗加立体定向放射外科(WBRT SRS)组、单纯立体定向放射治疗(SRT)组、全脑放疗加立体定向放射治疗(WBRT SRT)组.SRS治疗单次靶区平均周边剂量8～20Gy,总剂量20～32Gy;SRT治疗单次靶区平均周边剂量2～5Gy,总剂量25～60Gy;WBRT1.8～2Gy/次,总剂量30～40Gy.结果四组的局部控制率分别为47.0%、87.7%、86.5%和78.0%;中位生存期分别为5.0,11.0,11.5和10.0个月;局部无进展生存期分别为3.33,8.33,9.33和7.67个月;颅脑无新病灶生存期分别为4.11,8.57,9.03和6.12个月.在死因分析中,WBRT组死于脑转移的比率为57.6%,较其他三组高.而WBRT SRS组的晚期放射反应的发生率为12.2%,较其他组高.结论肺癌单发脑转移瘤患者的最佳治疗方式是单纯立体定向放射治疗,治疗失败后再行挽救性全脑照射或立体定向放疗.对于多发脑转移,全脑放疗加立体定向放射治疗(WBRT SRT)在提高生存率以及减少并发症方面优于其他治疗方法.