体部立体定向放疗的放射生物学研究进展

近年来,体部立体定向放疗(SBRT)被越来越多地应用于治疗各种实体肿瘤,并获得了显著的疗效。图像引导系统和放疗技术的进步,使SBRT在靶区内形成高剂量区域,靶区外剂量梯度迅速下降,在给予肿瘤大剂量照射的同时又尽可能地保护周围正常组织,实现了安全的“大分割”。目前,对于SBRT放射生物学尚缺乏规律性的认识,如线性二次(LQ)模型的适用性、再氧合的弱化、不同于常规分割放疗的额外细胞杀伤效应以及免疫增强作用等方面仍存有争议。本综述旨在对以上争议进行分析和探讨,以期加深对SBRT放射生物学特征的认识,进一步促进SBRT的临床应用。     

根治性前列腺癌低分割放疗的研究进展

放疗是局限性前列腺癌的重要治疗手段之一,既往根治性放疗为常规分割模式。近年来低分割放疗技术在根治性前列腺癌中的应用得到了快速发展,中等低分割放疗已被认为在有条件的单位可作为常规分割模式的替代方式,超低分割放疗(也称为立体定向放疗)在低中危患者中也有越来越多的证据。但高危前列腺癌的立体定向放疗的有效性及安全性还未得到充分...     

Cost-effectiveness of modern radiotherapy techniques in locally advanced pancreatic cancer

BACKGROUND:

Radiotherapy may improve the outcome of patients with pancreatic cancer but at an increased cost. In this study, the authors evaluated the cost‐effectiveness of modern radiotherapy techniques in the treatment of locally advanced pancreatic cancer.

METHODS:

A Markov decision‐analytic model was constructed to compare the cost‐effectiveness of 4 treatment regimens: gemcitabine alone, gemcitabine plus conventional radiotherapy, gemcitabine plus intensity‐modulated radiotherapy (IMRT); and gemcitabine with stereotactic body radiotherapy (SBRT). Patients transitioned between the following 5 health states: stable disease, local progression, distant failure, local and distant failure, and death. Health utility tolls were assessed for radiotherapy and chemotherapy treatments and for radiation toxicity.

RESULTS:

SBRT increased life expectancy by 0.20 quality‐adjusted life years (QALY) at an increased cost of $13,700 compared with gemcitabine alone (incremental cost‐effectiveness ratio [ICER] = $69,500 per QALY). SBRT was more effective and less costly than conventional radiotherapy and IMRT. An analysis that excluded SBRT demonstrated that conventional radiotherapy had an ICER of $126,800 per QALY compared with gemcitabine alone, and IMRT had an ICER of $1,584,100 per QALY compared with conventional radiotherapy. A probabilistic sensitivity analysis demonstrated that the probability of cost‐effectiveness at a willingness to pay of $50,000 per QALY was 78% for gemcitabine alone, 21% for SBRT, 1.4% for conventional radiotherapy, and 0.01% for IMRT. At a willingness to pay of $200,000 per QALY, the probability of cost‐effectiveness was 73% for SBRT, 20% for conventional radiotherapy, 7% for gemcitabine alone, and 0.7% for IMRT.

CONCLUSIONS:

The current results indicated that IMRT in locally advanced pancreatic cancer exceeds what society considers cost‐effective. In contrast, combining gemcitabine with SBRT increased clinical effectiveness beyond that of gemcitabine alone at a cost potentially acceptable by today's standards. Cancer 2012;. © 2011 American Cancer Society.     

肝癌立体定向体部放射治疗的剂量学研究

目的:探讨立体定向体部放射治疗(stereotactic body radiotherapy,SBRT)在原发性肝癌(Primary he-patic carcinoma,PHC)放疗中的剂量学特点和临床价值,证实SBRT是PHC放射治疗的发展方向。方法:2009年1月至8月,可行放疗的PHC患者50例,CT薄层定位扫描,将图像分别输入SBRT和三维适形放射治疗(3DCRT)计划系统,同一病例做两个治疗计划,对靶区内剂量分布、危及器官(OARs)受量、适形度等进行对比。结果:SBRT计划中靶区剂量显著高于3DCRT,正常肝脏和邻近OARs的重要剂量学指标均显著性低于3DCRT,两计划中适形指数(CI)和病灶覆盖率(Coverage)无统计学差异(P>0.05),均匀指数(HI)对比差异有显著性(P<0.05)。SBRT治疗后3个月左右复查CT,观察疗效。50例患者均完成治疗和接受随访复查,局部控制率为88%,半年、1年生存率分别为86%、70%。不良反应少且轻,经处理可缓解消失。结论:SBRT在肝癌放疗中具有明显的剂量学优势,值得推广运用。     

立体定向放射治疗在肝细胞癌治疗中的应用进展

立体定向放射治疗（stereotactic body radiation therapy，SBRT）是一种高精度的放射治疗技术，可以通过较少分次的照射提供高剂量、高精度的放射治疗。SBRT能够显著改善肝细胞癌（hepatocellular carcinoma，HCC）患者的局部控制和生存，对于等待肝移植的患者来说，SBRT也可以是一种有效和安全的桥接治疗。此外，SBRT已经显示出联合免疫检查点抑制剂应用的潜在作用。本文将就SBRT治疗HCC的有效性和安全性，并对SBRT联合免疫治疗进行综述。      

The Journey of Radiotherapy Dose Escalation in High Risk Prostate Cancer; Conventional Dose Escalation to Stereotactic Body Radiotherapy (SBRT) Boost Treatments

High risk prostate cancer (HR-PrCa) is a subset of localized PrCa with significant potential for morbidity and mortality associated with disease recurrence and metastasis. Radiotherapy combined with Androgen Deprivation Therapy has been the standard of care for many years in HR-PrCa. In recent years, dose escalation, hypo-fractionation and high precision delivery with immobilization and image-guidance have substantially changed the face of modern PrCa radiotherapy, improving treatment convenience and outcomes. Ultra-hypo-fractionated radiotherapy delivered with high precision in the form of stereotactic body radiation therapy (SBRT) combines delivery of high biologically equivalent dose radiotherapy with the convenience of a shorter treatment schedule, as well as the promise of similar efficacy and reduced toxicity compared to conventional radiotherapy. However, rigorous investigation of SBRT in HR-PrCa remains limited. Here, we review the changes in HR-PrCa radiotherapy through dose escalation, hypo- and ultra-hypo-fractionated radiotherapy boost treatments, and the radiobiological basis of these treatments. We focus on completed and on-going trials in this disease utilizing SBRT as a sole radiation modality or as boost therapy following pelvic radiation.     

基于直线加速器立体定向放疗计划设计与评估的若干物理问题

立体定向放射治疗(SRT)又称立体定向消融放疗(SABR),包括颅内立体定向放射外科和体部立体定向放疗(SBRT)。该技术具有分次剂量大、治疗次数少、等效生物剂量高、靶区外剂量跌落迅速等特点,可通过γ刀、Cyberknife、Tomotherapy、Vero 4D RT系统等相对特殊的设备实现,而基于直线加速器进行SBRT则更为普遍。SRT在计划设计和评估等相关物理问题与常规放疗不同,因此,有必要对其进行讨论,以指导临床应用和研究。     

立体定向体部放疗联合靶向药物治疗转移性肾癌的研究进展

立体定向体部放疗(Stereotactic body radiotherapy,SBRT)是近年来放疗取得的一个突破性进展,具有分次剂量高、生物学效应高、分割次数少等优势,可显著提高肾癌的放疗敏感性。分子靶向治疗显著延长了部分患者的无进展生存期和总生存期,但在大多数情况下产生全身用药的耐药性仍不可避免。近年来,SBRT联合靶向药物治疗转移性肾癌初步显示了有效性和安全性,有可能成为一种更有效的治疗方案。本文针对SBRT联合靶向药物治疗转移性肾癌研究进展进行综述。     

The role of stereotactic body radiotherapy and stereotactic radiosurgery in the re-irradiation of metastatic spinal tumors

Stereotactic body radiotherapy (SBRT) and stereotactic radiosurgery (SRS) are advanced radiotherapy delivery techniques that allow for the delivery of high-dose per fraction radiation. Advances in imaging technology and intensity modulation have allowed SRS and SBRT to be used for the treatment of tumors in close proximity to the spinal cord and cauda equina, in particular spinal metastases. While the initial treatment of spinal metastases is often conventional palliative radiotherapy, treatment failure is not uncommon, and conventional re-irradiation may not be feasible due to spinal cord tolerance. SBRT and SRS have emerged as important techniques for the treatment of spinal metastases in the proximity of previously irradiated spinal cord. Here we review the current data on the use of SBRT and SRS spinal re-irradiation, and future directions for these important treatment modalities.     

肺部立体定向放疗对外周血淋巴细胞的影响

背景与目的：靶向程序性死亡［蛋白］-1（programmed death-1，PD-1）/程序性死亡［蛋白］配体-1（programmed death ligand-1，PD-L1）的免疫检查点抑制剂已被批准用于多种恶性肿瘤的治疗，其治疗效应的发挥取决于T淋巴细胞的活化。放射治疗诱导的免疫原性细胞死亡可促进免疫反应，但同时辐射诱发的淋巴结细胞减少可能会降低免疫检查点抑制剂的效应。目前不同放疗技术、放疗部位、放疗范围对淋巴细胞的影响都尚不明确。探讨肺部立体定向放疗（stereotactic body radiotherapy，SBRT）的不同分割方式及剂量等参数对患者外周血淋巴细胞的影响。方法：回顾性分析2016—2018年间在郑州大学附属肿瘤医院接受肺部立体定向放疗的64例患者的相关临床资料。SBRT采用90％等剂量线覆盖计划靶体积（planning target volume，PTV），PTV为40~65 Gy，分割次数4~13次，生物等效剂量（biological equivalent dose，BED）为60~116 Gy，每天1次，每周照射最多5次。通过收集患者放疗前1周、放疗后1周、放疗后1个月和放疗后3个月的血常规数据，分析SBRT的各项参数与患者外周血绝对淋巴细胞计数变化的相关性。结果：外周血淋巴细胞计数在放疗后1周和1个月均出现不同程度的降低，在放疗后3个月基本恢复到放疗前水平。SBRT的各项参数中分割次数对淋巴细胞计数的影响较为突出，在放疗后1周和1个月，分割次数≤5次组的外周血淋巴细胞计数降低程度均显著小于分割次数＞5次组，分别为（1.68±0.63 vs 0.93±0.34，P=0.021）和（1.60±0.68 vs 0.95±0.41，P=0.004）。而不同分割剂量、总剂量、BED值在放疗前后各组对比淋巴细胞计数差异无统计学意义（P＞0.05）。结论：SBRT治疗后1周和1个月，分割次数≤5次组的外周血淋巴细胞计数降低程度显著小于分割次数＞5次组，在SBRT结束后3个月淋巴细计数基本恢复到放疗前水平。     

Hypofractionation in Hepatocellular Carcinoma – The Effect of Fractionation Size

The use of stereotactic body radiotherapy (SBRT) in hepatocellular carcinoma (HCC) has increased over the years. Several prospective studies have demonstrated its safety and efficacy, and randomised trials are underway. The advancement in technology has enabled the transition from three-dimensional conformal radiotherapy to highly focused SBRT. Liver damage is the primary limiting toxicity with radiation, with the incidence of grade 3 varying from 0 to 30%. The reported radiotherapy fractionation schedule for HCC, and in practice use, ranges from one to 10 fractions, based on clinician preference and technology available, tumour location and tumour size. This review summarises the safety and efficacy of various SBRT fractionation schedules for HCC.     

Lokal ablative nichtchirurgische Verfahren beim nichtkleinzelligen Bronchialkarzinom

Until recently conventional radiotherapy was the gold standard in the treatment of stage I non-small-cell lung cancer if a surgical approach was not possible due to severe comorbidities. This review summarizes the current status of modern local ablative approaches. The technique of stereotactic body radiotherapy (SBRT) consistently achieves local control rates of 90% and improves overall survival compared to conventional radiotherapy. SBRT is a safe procedure and provides a curative option for elderly patients and patients with very poor pulmonary function. Local tumor control after radiofrequency ablation is at best 70% and below 50% for tumors >3?cm. Consequently, SBRT is considered as non-surgical the treatment of choice.     

体部立体定向放射治疗早期可手术非小细胞肺癌

体部立体定向放疗是指应用单次或少数多次给予靶区高剂量照射的治疗方式。和常规放疗相比，该技术具有分割剂量大、精度高等特点。对于因高龄或合并严重心肺等内科疾病不能手术或不愿接受手术的早期非小细胞肺癌患者，SBRT已被确立为标准治疗。对于可手术病灶，SBRT能达到与手术相似的局部控制率。本研究将对SBRT用于早期可手术NSCLC患者的研究进展作一综述。     

GOECP/SEOR radiotheraphy guidelines for non-small-cell lung cancer

Non-small cell lung cancer (NSCLC) is a heterogeneous disease accounting for approximately 85% of all lung cancers. Only 17% of patients are diagnosed at an early stage. Treatment is multidisciplinary and radiotherapy plays a key role in all stages of the disease. More than 50% of patients with NSCLC are treated with radiotherapy (curative-intent or palliative). Technological advances-including highly conformal radiotherapy techniques, new immobilization and respiratory control systems, and precision image verification systems-allow clinicians to individualize treatment to maximize tumor control while minimizing treatment-related toxicity. Novel therapeutic regimens such as moderate hypofractionation and advanced techniques such as stereotactic body radiotherapy (SBRT) have reduced the number of radiotherapy sessions. The integration of SBRT into routine clinical practice has radically altered treatment of early-stage disease. SBRT also plays an increasingly important role in oligometastatic disease. The aim of the present guidelines is to review the role of radiotherapy in the treatment of localized, locally-advanced, and metastatic NSCLC. We review the main radiotherapy techniques and clarify the role of radiotherapy in routine clinical practice. These guidelines are based on the best available evidence. The level and grade of evidence supporting each recommendation is provided.     

非小细胞肺癌立体定向放疗所致放射性肺炎相关因素研究进展

立体定向放疗现已成为早期非小细胞肺癌治疗的重要选择。放射性肺炎是早期非小细胞肺癌患者立体定向放疗后主要不良反应。患者因素、肿瘤因素、治疗因素等都与早期非小细胞肺癌患者立体定向放疗后放射性肺炎的发生相关。近年来的相关研究进一步明确了这些因素与放射性肺炎的关联,而且对与RP发生相关的预测因素进行了进一步探讨。本文对近年来的相关研究结果进行了综述。     

原发性肝癌SBRT研究进展

SBRT杀伤肿瘤细胞的机制可能与常规分割放疗不同,可体现在以下两个方面:单次大剂量照射可使肿瘤细胞膜破坏,释放肿瘤特异性抗原,成为“原位肿瘤疫苗”,继而可激发免疫系统杀灭残余肿瘤;当单次分割剂量>8~10 Gy时,照射1~6 h后可通过酸性鞘磷脂酶途径介导血管内皮细胞快速凋亡,进而肿瘤血管闭塞,出现二次肿瘤杀伤效应。本文综述原发性肝癌利用SBRT临床研究进展,旨在了解其是否通过上述机制增加了临床疗效。     

肝癌立体定向体部放射治疗的剂量学研究

目的：探讨立体定向体部放射治疗（stereotactic body radiotherapy,SBRT）在原发性肝癌（Primary he-patic carcinoma,PHC）放疗中的剂量学特点和临床价值,证实SBRT是PHC放射治疗的发展方向。方法：2009年1月至8月,可行放疗的PHC患者50例,CT薄层定位扫描,将图像分别输入SBRT和三维适形放射治疗（3DCRT）计划系统,同一病例做两个治疗计划,对靶区内剂量分布、危及器官（OARs）受量、适形度等进行对比。结果：SBRT计划中靶区剂量显著高于3DCRT,正常肝脏和邻近OARs的重要剂量学指标均显著性低于3DCRT,两计划中适形指数（CI）和病灶覆盖率（Coverage）无统计学差异（P〉0.05）,均匀指数（HI）对比差异有显著性（P〈0.05）。SBRT治疗后3个月左右复查CT,观察疗效。50例患者均完成治疗和接受随访复查,局部控制率为88%,半年、1年生存率分别为86%、70%。不良反应少且轻,经处理可缓解消失。结论：SBRT在肝癌放疗中具有明显的剂量学优势,值得推广运用。     

肾细胞癌立体定向体部放疗的研究进展

肾细胞癌(renal cell carcinoma,RCC)传统上被认为是放射治疗抵抗性肿瘤,手术是原发性RCC的标准治疗手段。因高龄及临床并发症丧失手术机会的患者,可通过立体定向体部放疗(stereotactic body radiation therapy,SBRT)提高RCC局部控制(local control,LC)率,并显示较好的疗效。SBRT结合图像引导放疗(image-guided radiation therapy,IGRT)技术实现靶区的精确定位,对周围正常组织损伤小,具有LC率高、毒性低并可延长无法手术患者生存期等优点。因SBRT应用于RCC的LC率、不良反应以及生存期等结果,根据机器及放射剂量的不同而有所变化,本文将就SBRT应用于转移性和原发性RCC的研究进展进行综述。      

Vertebral compression fracture during stereotactic body radiotherapy for spinal metastasis: A rare case of tracking failure

Spinal metastasis are a daily challenge in clinical practice. Stereotactic body radiotherapy (SBRT) allows delivery of definitive treatment with excellent long-term control rates. Its implementation needs dedicated devices and day-to-day image-guided radiotherapy (IGRT). The XSight™ spine tracking system, integrates with the CyberKnife® (Accuray™), provides a fiducial-free tracking system for spinal SBRT. We report a rare case of tracking failure during treatment due to the occurrence of a vertebral compression fracture (VCF).     

早期非小细胞肺癌的体部立体定向放射治疗进展

体部立体定向放射治疗（stereotactic body radiotherapy,SBRT）成为医学上不能手术的早期非小细胞肺癌（non-small cell lung cancer,NSCLC）的标准治疗方式。近十年的临床证据表明SBRT替代手术治疗效果可观。由于毒副作用小,SBRT同样适用于肺功能差、患有某些严重并发症的老年患者。最近针对可手术早期NSCLC患者的对比研究中发现SBRT可能同样适用于这一群体,但这些可观的结果仍需要长期随访的前瞻性实验的验证。本文就SBRT治疗早期非小细胞肺癌的临床进展做一综述。