CBCT图像引导下SBRT治疗肺部原发灶或转移灶的初步研究

[目的]评价CBCT图像引导技术下SBRT治疗原发性肺癌或肺转移瘤的安全性和初步疗效。[方法]2012年8月至2013年10月共9例患者在浙江省肿瘤医院接受CBCT图像引导下SBRT胸部放疗,中位年龄68岁。每次照射前行KV级CBCT扫描并在线配准。每次照射剂量5．0～12．5Gv．每日1次,中位照射次数8次（4～10次）;BED76．8～112．5Gy（中位96Gy）。[结果]9例患者均安全完成放疗,总有效率为77．8％。其中CR1例（11．1％）,PR6例（66．7％）,SD2例（22．2％）,无PD患者,未出现3度以上放射性毒副反应。中位随访8．8个月（1．3～14．6个月）,1年局部控制率及总生存率分别为88．9％和100％。[结论]CBCT图像引导下SBRT治疗早期肺癌或肺转移瘤近期疗效明确．毒副反应低．远期疗效有待进一步随访。     

Stereotactic Body Radiation Therapy for Central Early-Stage NSCLC: Results of a Prospective Phase I/II Trial

Introduction

We report results from a prospective phase I/II trial for patients with centrally located, early-stage NSCLC receiving stereotactic body radiation therapy.

Stereotactic Body Radiation Therapy in the Management of Oligometastatic and Oligoprogressive Bladder Cancer and Other Urothelial Malignancies

AimsBladder cancer represents the most common type of urothelial carcinoma, with a median overall survival of 12.5–15 months in the case of metastatic disease. We evaluated the role of stereotactic body radiation therapy (SBRT) in the management oligometastatic urothelial cancer.Materials and methodsData on patients with a maximum of five metastases were collected from three institutions. Concomitant systemic therapy was allowed. End points were the local control of treated metastases, distant progression-free survival (PFS), overall PFS and overall survival.ResultsData for 82 lesions and 61 patients were included. The primary tumour was located in the bladder in 82% of patients, followed by kidney pelvis (11.5%). The most common treated site was lung (40.2%). Twenty-nine (47.5%) and 14 (23%) patients received systemic therapy before and during SBRT, respectively. The median BED10 value was 78.7 Gy. The median follow-up was 17.2 months. Rates of local control at 1 and 2 years were 92% and 88.9%, respectively, with correlation with systemic therapy before SBRT (hazard ratio 2.62, P = 0.034). Overall PFS at 1 and 2 years was 47.9% and 38.1%, respectively. The number of metastases was a predictive factor (hazard ratio 2.65, P = 0.008). The median overall survival was 25.6 months. Total dose (hazard ratio 0.93, P = 0.003) and BED10 (hazard ratio 0.97, P = 0.006) were correlated with overall survival. No grade ≥2 adverse events were reported.ConclusionsSBRT represents an effective and safe treatment in metastatic urothelial carcinoma. Prospective randomised trials are necessary to better evaluate the benefit on delaying the onset of new systemic therapies.     

统计学不确定度对非小细胞肺癌SBRT计划的影响

目的：研究不同统计学不确定度在Ｘ射线体素蒙卡算法下,对于肺癌立体定向放射治疗计划的结果影响。方法：使用医科达Monaco5.11临床计划设计系统,在同台加速器实施,采用相同的计划函数配置条件和参数设置要求的情况下,分别采用每个计划0.5％、1％、3％、5％的SU值对肺癌SBRT病例进行计划设计,并对计划数据结果、剂量分布及XVMA算法中的特征数据进行统计分析。结果：SU值在0.5％～5％的变化中,PTVD95％和PTVDMAX逐步提高(Ｐ＜0.05),SU1％～3％组间差异最大;危及器官受量以及靶区均匀性指数受到影响较小(Ｐ＞0.05);XVMA剂量计算时间SU0.5％～1％差异最大300s以上,SU3％～5％无差异;粒子历史压缩模拟次数SU0.5％～1％差异最大为199.4,SU3％～5％无差异;整体计划不确定度极值差异－1.18;受到SU值提高的影响,剂量计算时长增加,参与模拟粒子密度降低,整体计划不确定度增加。不同SU值对于计划验证通过率和等中心点剂量影响不明显(Ｐ＞0.05),但随SU值增大有降低趋势;110％以上剂量分布各组间差异明显,SU0.5％计划中分布体积最小。结论：对于肺癌SBRT计划,由于其单次剂量较高(一般单次处方剂量在5Ｇy以上)的特点,在可接受的时间成本下,应保证更高的计划验证通过率,本研究推荐在肺癌SBRT计划中使用0.5％,最大不超过1％的SU值。     

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。     

Patterns of Pretreatment Diagnostic Assessment in Patients Treated with Stereotactic Body Radiation Therapy (SBRT) for Non-Small Cell Lung Cancer (NSCLC): Special Characteristics in the COVID Pandemic and Influence on Outcomes

The pandemic raised a discussion about the postponement of medical interventions for non-small cell lung cancer (NSCLC). We analyzed the characteristics of pretreatment diagnostic assessment in the pandemic and the influence of diagnostic assessment on outcomes. A total of 96 patients with stereotactic body radiation therapy (SBRT) for NSCLC were included. The number of patients increased from mean 0.9 (2012–2019) to 1.45 per month in the COVID era (p < 0.05). Pandemic-related factors (contact reduction, limited intensive care unit resources) might have influenced clinical decision making towards SBRT. The time from pretreatment assessment (multidisciplinary tumor board decision, bronchoscopy, planning CT) to SBRT was longer during the COVID period (p < 0.05). Reduced services, staff shortage, or appointment management to mitigate infection risks might explain this finding. Overall survival, progression-free survival, locoregional progression-free survival, and distant progression-free survival were superior in patients who received a PET/CT scan prior to SBRT (p < 0.05). This supports that SBRT guidelines advocate the acquisition of a PET/CT scan. A longer time from PET/CT scan/conventional staging to SBRT (<10 vs. ≥10 weeks) was associated with worse locoregional control (p < 0.05). The postponement of diagnostic or therapeutic measures in the pandemic should be discussed cautiously. Patient- and tumor-related features should be evaluated in detail.     

A Phase I/II Study of Stereotactic Hypofractionated Once-weekly Radiation Therapy (SHORT) for Prostate Cancer

AimsStereotactic radiation therapy has been investigated predominantly in patients with low–intermediate-risk disease. We conducted a clinical trial of stereotactic hypofractionated radiation therapy delivered in once-weekly fractions on patients with all-risk non-metastatic disease to test feasibility, acute toxicities and patient-reported outcomes.Materials and methodsIn this phase I/II study, 30 patients with prostatic adenocarcinoma, any Gleason score, T1-4N0 and prostate-specific antigen ≤60 ng/ml were treated with volumetric intensity modulated arc radiation therapy to a dose of 35 Gy in five fractions delivered once weekly. Patients with high-risk disease also received elective nodal irradiation to a dose of 25 Gy in five fractions simultaneously. Androgen deprivation was offered to intermediate- and high-risk patients. The primary outcome was acute toxicity. Secondary outcome measures included biochemical control and late toxicity. Patient-reported outcomes were measured using the International Prostate Symptom Score and European Organization for Research and Treatment of Cancer (EORTC) Quality-of-Life Questionnaire (QLQ).ResultsAll 30 patients completed treatment per-protocol. Most patients had T3 (60%) and Gleason 7 (50%) tumours. The median prostate-specific antigen was 17 ng/ml. High-risk disease was present in 20 patients (66.7%). There was a low incidence of acute toxicities (grade 2 + urinary 3.3%, grade 2 rectal 0%). Within the EORTC QLQ framework, only the urinary symptom score showed a clinically meaningful worsening from a mean of 20/100 at baseline to 34/100 at the end of treatment (P < 0.001), but reduced to 24/100 at 6 months (P = 0.08). With a median follow-up of 41.5 months, two patients each reported grade 2 late urinary and rectal toxicity. The 3- and 4-year biochemical control rates were 96.7 and 87.9%, respectively.ConclusionIn a cohort of mainly high-risk cancers, stereotactic once-weekly radiation therapy was easy to implement and well tolerated, with a low incidence of acute and late toxicity and excellent biochemical control.