再程立体定向放射治疗的应用

肿瘤经放射治疗或者多种方法联合治疗后,局部复发经常出现,但局部再程放疗仅适用于少数病人,因其会引起潜在的严重并发症,特别是对大体积的肿瘤进行再程放疗时。采用立体定向放射治疗(SBRT)对复发的椎体转移瘤、头颈部肿瘤、盆腔肿瘤进行再程放疗,不仅能够提高局部控制率并减轻症状,同时还能够减少正常组织不良反应。SBRT在临床上是一种安全有效的方法,建议将SBRT作为控制局部症状的重要治疗手段。     

肾细胞癌的立体定向体部放射治疗策略及进展

肾细胞癌(RCC)是泌尿生殖系统中侵袭性最高的恶性肿瘤之一,预后不佳,尤其是发生RCC转移的患者。传统观点一般认为肾细胞癌对放疗不敏感。立体定向体部放射治疗(SBRT)与常规放疗相比,具有高精准度、较高照射剂量、对周围组织损伤小等特点。近年来,SBRT在原发性及转移性RCC治疗中均展现了确切的疗效。SBRT联合靶向治疗以及免疫治疗等联合方案可以提高原发和晚期转移RCC患者的肿瘤局部控制率,且不良反应较小。本文就SBRT 联合靶向治疗以及免疫治疗的策略和进展等方面进行综述。     

儿童成髓细胞瘤的放疗及失败的方式

以往成髓细胞瘤治疗失败原因主要是后颅窝的复发,但提高剂量、改进放疗技术却未见疗效提高,局部控制不能得到保证且增加远期副作用。肿瘤转移至幕上及脊髓与放疗质量有关,另外戴眼罩所致筛板剂量严重不足亦可致幕上复发。作者回顾分析了1972～1991年在瑞士治疗的86例少儿成髓细胞瘤术后全脑全脊髓放疗,男66例,女20例,诊断时     

头颈部肿瘤IMRT治疗后局部复发问题探讨

调强适形放疗(IMRT)能更好地提高靶区剂量,减少靶区周围正常组织的剂量,特别适宜头颈部这些比较靠近重要器官的肿瘤的治疗.在头颈部肿瘤的治疗中,IMRT比常规放疗有更好的剂量分布优势,在不影响肿瘤控制率和无瘤生存率的情况下,能够降低临近重要器官毒性,从而降低脑、脊髓损伤以及口干等副作用的发生率.IMRT显著提高了靶区的覆盖范围和避开正常组织,然而在头颈部肿瘤的治疗中局部复发依然是治疗失败的主要原因.分析了1999年以来关于头颈部肿瘤局部复发的文献资料,对使用IMRT治疗头颈部肿瘤病人的局部复发问题进行综述.     

立体定向放疗在非小细胞肺癌治疗中的应用

体部立体定向放疗（stereotactic body radiation therapy,SBRT）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,具有分割剂量大、精度高等特点。其在肺部肿瘤中的应用可归纳为以下3点：①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（T_1-2N₀M₀）非小细胞肺癌（non-small cell lung cancer,NSCLC）,SBRT已确立标准治疗的地位。②对于可手术的早期NSCLC,SBRT初步应用的结果并不逊于手术。③对于肺内孤立转移灶（1~3个）,在全身治疗的基础上给与SBRT已逐步被接受。本文对此作一综述。     

头颈部肿瘤IMRT治疗后局部复发问题探讨

调强适形放疗（IMRT）能更好地提高靶区剂量，减少靶区周围正常组织的剂量，特别适宜头颈部这些比较靠近重要器官的肿瘤的治疗。在头颈部肿瘤的治疗中，IMRT比常规放疗有更好的剂量分布优势，在不影响肿瘤控制率和无瘤生存率的情况下，能够降低临近重要器官毒性，从而降低脑、脊髓损伤以及口干等副作用的发生率。IMRT显著提高了靶区的覆盖范围和避开正常组织，然而在头颈部肿瘤的治疗中局部复发依然是治疗失败的主要原因。分析了1999年以来关于头颈部肿瘤局部复发的文献资料，对使用IMRT治疗头颈部肿瘤病人的局部复发问题进行综述。     

医源性肿瘤腹壁种植转移五例分析

目的探讨医源性肿瘤腹壁种植转移的诊断和治疗。方法结合文献回顾性分析5例医源性肿瘤腹壁种植转移患者的临床诊疗过程及转归。结果 5例患者中,原发癌为胆管癌1例,肝癌4例。分别于医源性操作后42~94 d发现腹壁种植转移,1例患者半年后因恶液质去世,种植转移灶较前稍增大;2例肝癌TACE治疗的同时给予种植转移灶TACE治疗,2例种植转移灶给予局部放疗,4例患者转移灶均稳定,TACE及放疗各有1例患者出现局部皮肤损伤。结论医源性诊疗操作存在一定程度的肿瘤腹壁种植转移的风险,结合病史、影像学、细胞学及病理检查可明确诊断,局部治疗具有一定优势,但对于终末期患者在转移灶不影响生活质量的前提下可暂时给予观察。     

化疗结合适形调强放射治疗鼻咽癌的护理体会

适形调强放射治疗(Intensity modulated radia-tion therapy,I MRT)是目前国际上最先进的放射治疗手段,它能够使照射的高剂量在人体内的三维空间上与靶区的实际形状一致,使靶区内及靶表面的剂量处处相等,从而保护肿瘤周围正常组织,提高肿瘤区照射剂量,降低局部复发率,延长病人生存期[1]。但放射治疗后仍有较高的局部复发和远处转移。尤其是Ⅲ、Ⅳ期鼻咽癌患者远处转移率较高。近年来,国内外学者提出,化疗与放疗联合治疗鼻咽癌患者的方案,不仅可使局部肿瘤缩小,增强肿瘤细胞对放疗的敏感性,提高局部控制率,同时亦可消除亚临床病灶,降低远处…     

32P胶体局部给药防治H22移植瘤淋巴道转移的实验研究

目的探讨不同剂量的^32P胶体局部注射对小鼠H22移植瘤和区域淋巴结转移灶的治疗作用。方法应用小鼠H22腹水型肝癌淋巴道转移模型，通过肿瘤组织局部给药，观察^32P胶体在模型小鼠移植瘤、区域淋巴结及全身各器官、组织内的分布。结果^32P胶体局部给药后主要聚集在瘤体注射局部和区域淋巴结内，而在肝、脾、肺等脏器分布的活度较低。区域淋巴结聚集的活度随给药剂量增高而递增。治疗早期瘤体和胭窝淋巴结转移灶呈现局灶性坏死。后期移植瘤和区域淋巴结转移灶的瘤组织呈现出血、坏死。结论^32P胶体瘤体给药可在局部富集，并可经淋巴道转运、聚集于区域淋巴结，对肿瘤组织和邻近的淋巴结转移灶具有明显的杀伤作用。     

立体定向放疗应用于肺寡转移灶的疗效与预后

目的 分析立体定向放射治疗（stereotactic body radiation therapy,SBRT）应用于肺寡转移灶的疗效与预后。方法 回顾性分析2012-2018年本院SBRT肺寡转移患者104例临床资料,2015年12月前的患者采用调强放疗（intensity modulated radiation therapy,IMRT）技术行立体定向放射治疗,2015年12月后的患者采用螺旋断层放疗（helical tomotherapy,HT）技术行立体定向放射治疗,用Kaplan-Meier方法计算局部控制（local control,LC）、无进展生存期（progression-free survival,PFS）及总生存（overall survival,OS）,Cox回归模型进行单因素与多因素分析,NCICTCAE V4.0标准评价放疗的不良反应。结果 1、2、3年的LC分别为86.6%、75.9%、72.3%,PFS分别为40.9%、28.4%、22.1%,OS分别为75.9%、53.2%、43.53%,中位OS为26.6个月。多因素分析显示原发肿瘤的病理类型、肺部结节的体积及SBRT治疗前癌胚抗原水平（carcino-embryonic antigen,CEA）为LC的独立预后因素（χ²=28.66,P<0.05）,SBRT后的进展方式为OS的独立预后因素（χ²=40.01,P<0.05）,HT-SBRT与IMRT-SBRT的LC及OS差异无统计学意义（P>0.05）;治疗的主要不良反应为放射性肺炎（25例,24.04%）,2级及以上放射性肺炎的发生率不超过7%。结论 SBRT应用于肺寡转移灶的治疗局部控制率高,不良反应可接受,HT-SBRT与IMRT-SBRT的疗效相当,不良反应差异无统计学意义,可广泛应用于临床。     

Radiation pneumonitis after stereotactic radiation therapy for lung cancer

Stereotactic body radiation therapy (SBRT) has a local control rate of 95% at 2 years for non-small cell lung cancer (NSCLC) and should improve the prognosis of inoperable patients, elderly patients, and patients with significant comorbidities who have early-stage NSCLC. The safety of SBRT is being confirmed in international, multi-institutional Phase II trials for peripheral lung cancer in both inoperable and operable patients, but reports so far have found that SBRT is a safe and effective treatment for early-stage NSCLC and early metastatic lung cancer. Radiation pneumonitis (RP) is one of the most common toxicities of SBRT. Although most post-treatment RP is Grade 1 or 2 and either asymptomatic or manageable, a few cases are severe, symptomatic, and there is a risk for mortality. The reported rates of symptomatic RP after SBRT range from 9% to 28%. Being able to predict the risk of RP after SBRT is extremely useful in treatment planning. A dose-effect relationship has been demonstrated, but suggested dose-volume factors like mean lung dose, lung V20, and/or lung V2.5 differed among the reports. We found that patients who present with an interstitial pneumonitis shadow on computed tomography scan and high levels of serum Krebs von den Lungen-6 and surfactant protein D have a high rate of severe radiation pneumonitis after SBRT. At our institution, lung cancer patients with these risk factors have not received SBRT since 2006, and our rate of severe RP after SBRT has decreased significantly since then.     

Stereotactic body radiotherapy (SBRT) in the management of extracranial oligometastatic (OM) disease

Objective:

A review of stereotactic body radiotherapy (SBRT) for oligometastases defined as three or fewer sites of isolated metastatic disease. The aim was to identify local control, overall survival (OS) and progression-free survival (PFS) of patients receiving SBRT for oligometastatic (OM) disease.

Methods:

Data were analysed for SBRT delivered between 01 September 2010 and 31 March 2014. End points included local control, PFS, OS and toxicity.

Results:

76 patients received SBRT. The median age was 60 years (31–89 years). 44 were male. Median follow-up was 12.3 months (0.2–36.9 months). Major primary tumour sites included colorectal (38%), the breast (18%) and the prostate (12%). The treatment sites included lymph nodes (42%), the bone and spine (29%) and soft tissue (29%). 42% were previously treated with conventional radiotherapy. 45% were disease free after SBRT. 4% had local relapse, 45% had distant relapse, and 6% had local and distant relapse. Local control was 89%. The OS was 84.4% at 1 year and 63.2% at 2 years. PFS was 49.1% at 1 year and 26.2% at 2 years. Toxicities included duodenal ulcer and biliary stricture formation.

Conclusion:

SBRT can achieve durable control of OM lesions and results in minimal radiation-induced morbidity.

Advances in knowledge:

This cohort is one of the largest reported to date and contributes to the field of SBRT in oligometastases that is emerging as an important research area. It is the only study reported from the UK and uses a uniform technique throughout. The efficacy and low toxicity with durable control of local disease with this approach is shown, setting the foundations for future randomized studies.Stereotactic body radiotherapy (SBRT) allows us to deliver ablative doses of radiation to extracranial sites, and this treatment modality can be considered in the setting of oligometastatic (OM) disease. Traditionally, systemic agents have been the mainstay of the management of metastatic disease, however, we have entered an era where in certain settings long-term local control or cure can be achieved. The idea of an OM state (defined as 1–3 isolated metastatic deposits) was first proposed in 1995 by Hellman and Weichselbaum¹ when they suggested that for many cancers, a few metastases exist at first, before the malignant cells acquire widespread metastatic potential. Following this, Niibe and Hayakawa² described the concept of oligorecurrence that whilst similar to oligometastases has control of the primary site of the malignancy allowing local therapies to achieve control of metastatic sites. Radical treatment of oligometastases and/or oligorecurrences may therefore achieve local control or cure in carefully selected cases. Local therapies including surgical resection, irradiation and radiofrequency ablation are radical treatment options to achieve this.^1,2 Local control rates of 80% have been achieved from several non-randomized studies of SBRT for oligometastases, and SBRT has been shown to be safe and effective.³     

Radiation-induced myositis mimicking chest wall tumor invasion in two patients with lung cancer: a PET/CT study

Two patients with lung cancer who had undergone stereotactic body radiation therapy (SBRT) exhibited increased F-18 FDG uptake in the chest wall after 6 months and 18 months, respectively, after SBRT. The prescribed dose of 50 Gy to the planning target volume was delivered on 4 consecutive days in each patient. It is important for nuclear medicine physicians to be familiar with F-18 FDG PET/CT findings ascribed to radiation-induced myositis in lung cancer patients treated with SBRT so that an appropriate differential diagnosis can be established.     

Stereotactic body radiotherapy for adrenal oligometastasis in lung cancer patients

Objective:To report our experience on stereotactic body radiotherapy (SBRT) in adrenal metastases from lung cancer.Methods:37 oligometastatic lung cancer patients with 38 adrenal metastases submitted to SBRT were retrospectively analyzed. SBRT was delivered by volumetric modulated arc therapy (VMAT) or helical tomotherapy (HT). Primary study end point was local recurrence-free survival (LR-FS) and secondary end points were distant-progression free survival (d-PFS) and overall survival (OS).Results:Median age was 67 years and primary tumor was non-small-cell lung cancer in 27 (73%) and small-cell lung cancer in 10 (27%) patients. Adrenal metastases were in the left side in 66% cases. Median prescribed dose was 30 Gy in 5 fractions for a median biologically equivalent dose (α/β ratio 10  Gy, BED10) of 48 Gy. Most patients (62%) were submitted to SBRT alone, while the others (38%) received chemo-, immune- or target- therapies. Median follow-up was 10.5 months, median OS 16 months and median d-PFS 3 months. 27 (70%) patients obtained a local control with a median LR-FS of 32 months. LR-FS was significantly related to BED10 with a better LC with BED10 ≥72 Gy, 1- and 2 year LR-FS rates were 54.1±11.6% and 45±12.7% vs 100 and 100% for BED ≤59.5 Gy and BED ≥72 Gy, respectively (p = 0.05). There was no severe toxicity.Conclusion:SBRT was effective and safe in lung cancer adrenal metastases. A dose–response relationship was found between BED10 >72 Gy and better local control. No significant toxicity was registered thanks to the respect of dose constraints and suspension of chemo- and target-therapies.Advances in knowledge:SBRT with a BED10 >72 Gy is an effective treatment for adrenal oligometastatic lung cancer patients.     

Radiation injury of the lung after stereotactic body radiation therapy (SBRT) for lung cancer: A timeline and pattern of CT changes

Stereotactic body radiation therapy (SBRT) is a new radiotherapy treatment method that has been applied to the treatment of Stage I lung cancers in medically inoperable patients, with excellent clinical results. SBRT allows the delivery of a very high radiation dose to the target volume, while minimizing the dose to the adjacent normal tissues. As a consequence, CT findings after SBRT have different appearance, geographic extent and progression timeline compared to those following conventional radiation therapy for lung cancer. In particular, SBRT-induced changes are limited to the “shell” of normal tissue outside the tumor and have a complex shape. When SBRT-induced CT changes have a consolidation/mass-like appearance, the differentiation from tumor recurrence can be very difficult. An understanding of SBRT technique as it relates to the development of SBRT-induced lung injury and familiarity with the full spectrum of CT manifestations are important to facilitate diagnosis and management of lung cancer patients treated with this newly emerging radiotherapy method.     

Implementation and evaluation of modified dynamic conformal arc (MDCA) technique for lung SBRT patients following RTOG protocols

To implement modified dynamic conformal arc (MDCA) technique and Radiation Therapy Oncology Group (RTOG) protocols in our clinic for stereotactic body radiation therapy (SBRT) treatment of patients with Stage I/II non–small cell lung cancer. Five patients with non–small cell lung cancer have been treated with SBRT. All the patients were immobilized using CIVCO Body Pro-Lok system and scanned using GE 4-slice computed tomography. The MDCA technique that was previously published was adopted as our planning technique, and RTOG protocols for the lung SBRT were followed. The patients were treated on Novalis Tx system with cone-beam computed tomography imaging guidance. All the patient plans passed the RTOG criteria. The conformal index ranges from 0.99 to 1.12 for the planning target volume, and the biological equivalent dose for the planning target volume is overall 100 Gy. Critical structures (lung, spinal cord, brachial plexus, skin, and chest wall) also meet RTOG protocols or published data. A 6-month follow-up of one of the patients shows good local disease control. We have successfully implemented the MDCA technique into our clinic for the lung SBRT program. It shows that the MDCA is useful and efficient for the lung SBRT planning, with the plan quality meeting the RTOG protocols.