3-Dimensional target coverage assessment for MRI guided esophageal cancer radiotherapy.
- 作者列表："Boekhoff MR","Defize IL","Borggreve AS","Takahashi N","van Lier ALHMW","Ruurda JP","van Hillegersberg R","Lagendijk JJW","Mook S","Meijer GJ
PURPOSE:This study aimed to quantify the coverage probability for esophageal cancer radiotherapy as a function of a preset margin for online MR-guided and (CB)CT-guided radiotherapy. METHODS:Thirty esophageal cancer patients underwent six T2-weighted MRI scans, 1 prior to treatment and 5 during neoadjuvant chemoradiotherapy at weekly intervals. Gross tumor volume (GTV) and clinical target volume (CTV) were delineated on each individual scan. Follow-up scans were rigidly aligned to the bony anatomy and to the clinical target volume itself, mimicking two online set-up correction strategies: a conventional CBCT-guided set-up and a MR-guided set-up, respectively. Geometric coverage probability of the propagated CTVs was assessed for both set-up strategies by expanding the reference CTV with an isotropic margin varying from 0 mm to 15 mm with an increment of 1 mm. RESULTS:A margin of 10 mm could resolve the interfractional changes for 118 out of the 132 (89%) analyzed fractions when applying a bone-match registration, whereas the CTV was adequately covered in 123 (93%) fractions when the registration was directly performed at the CTV itself (soft-tissue registration). Closer analyses revealed that target coverage violation predominantly occurred for distal tumors near the junction and into the cardia. CONCLUSION:Online MR-guided soft-tissue registration protocols exhibited modest improvements of the geometric target coverage probability as compared to online CBCT-guided bone match protocols. Therefore, highly conformal target irradiation using online MR-guidance can only be achieved by implementing on-table adaptive workflows where new treatment plans are daily generated based on the anatomy of the day.
目的: 本研究旨在量化食管癌放疗的覆盖概率，作为在线 MR 引导和 (CB)CT 引导放疗预设边缘的函数。 方法: 30 例食管癌患者接受了 6 T2-weighted MRI 扫描，1 例在治疗前和 5 例在新辅助放化疗期间每周间隔。在每个个体扫描上勾画大体肿瘤体积 (GTV) 和临床靶体积 (CTV)。随访扫描与骨解剖学和临床目标体积本身严格对齐，模拟两种在线设置矫正策略: 常规 CBCT 引导设置和 MR 引导设置。通过扩展各向同性裕度从 0毫米变化到 15毫米，增量为 1毫米的参考 CTV，评估了两种设置策略的传播 CTV 的几何覆盖概率。 结果: 当应用骨匹配配准时，10毫米的余量可以解决 118 (132) 分析分数中的 89% 的分数间变化,而当直接在 CTV 本身进行注册 (软组织注册) 时，CTV 被 123 (93%) 个分数充分覆盖。更密切的分析显示，侵犯目标覆盖主要发生在连接处附近和进入贲门的远端肿瘤。 结论: 与在线 CBCT 引导的骨匹配方案相比，在线 MR 引导的软组织配准方案显示了几何目标覆盖概率的适度改善。因此，使用在线 MR 引导的高适形靶照射只能通过实施基于当天解剖结构的日常生成新治疗计划的台式自适应工作流来实现。
METHODS:PURPOSE:The purpose of this study was to compare the survival and toxicities in cervical esophageal squamous cell carcinoma (CESCC) treated by concurrent chemoradiothrapy with either three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiotherapy (IMRT) techniques. Materials and Methods:A total of 112 consecutive CESCC patients were retrospectively reviewed. 3D-CRT and IMRT groups had been analyzed by propensity score matching method, with sex, age, Karnofsky performance status, induction chemotherapy, and tumor stage well matched. The Kaplan-Meier method and Cox proportional hazards model were used for overall survival (OS) and progression-free survival (PFS). Toxicities were compared between two groups by Fisher exact test. RESULTS:With a median follow-up time of 34.9 months, the 3-year OS (p=0.927) and PFS (p=0.859) rate was 49.6% and 45.8% in 3D-CRT group, compared with 54.4% and 42.8% in IMRT group. The rates of grade ≥ 3 esophagitis, grade ≥ 2 pneumonitis, esophageal stricture, and hemorrhage were comparable between two groups, while the rate of tracheostomy dependence was much higher in IMRT group than 3D-CRT group (14.3% vs.1.8%, p=0.032). Radiotherapy technique (hazard ratio [HR], 0.09; 95% confidence interval [CI], 0.01 to 0.79) and pretreatment hoarseness (HR, 0.12; 95% CI 0.02 to 0.70) were independently prognostic of tracheostomy dependence. CONCLUSION:No survival benefits had been observed while comparing IMRT versus 3D-CRT in CESCC patients. IMRT with fraction dose escalation and pretreatment hoarseness were considered to be associated with a higher risk for tracheostomy dependence. Radiation dose escalation beyond 60 Gy should be taken into account carefully when using IMRT with hypofractionated regimen.
METHODS::The radial force of esophageal stents may not completely change during extraction and therefore, the procedure of stent removal may cause tissue damage. The present study reports the manufacture of 2 novel detachable stents, which were designed to reduce tissue damage through their capacity to be taken or fall apart prior to removal and evaluated the supporting properties of these stents and the extent of local mucosal injury during their removal. The stents were manufactured by braiding, heat-setting, coating and connecting. The properties of the stents were evaluated by determining the following parameters: Expansion point, softening point, stent flexibility, radial compression ratio and radial force. A total of 18 rabbits with induced esophageal stricture were randomly assigned to 3 groups as follows: Detachable stent (DS) group, biodegradable stent (BS) group and control group. The stricture rate, complications, survival, degradation and stent removal were observed over 8 weeks. The stents of the DS and BS groups provided a similar supporting effect. The stricture rate, incidence of complications and survival were also similar between the 2 groups, while significant differences were noted between the DS and control groups and between the BS and control groups. In the BS group, the stents were degraded and moved to the stomach within 7 weeks (2 in 6 weeks and 3 in 7 weeks). The debris was extracted using biopsy forceps. In the DS group, all stents were easy to remove and 2 cases exhibited minor hemorrhage. In conclusion, the 2 types of novel detachable stent provided an equally efficient supporting effect in vitro and in vivo and may reduce the incidence of secondary injury during stent removal.
METHODS:BACKGROUND:Immune imbalance and inflammation have been suggested as key factors of Barrett's esophagus (BE) pathway towards adenocarcinoma. The neutrophil-lymphocyte ratio (NLR) indirectly reflects the relation between innate and adaptive immune systems and has been studied in premalignant conditions as a biomarker for cancer diagnosis. Our aim was to investigate if increasing values of NLR correlated with advancing stages of BE progression to dysplasia and neoplasia. METHODS:We retrospectively analyzed data of patients with biopsies reporting BE between 2013 and 2017 and with a complete blood count within 6 months from the endoscopy, as well as patients with esophageal adenocarcinoma (EAC). NLR was calculated as neutrophil count/lymphocyte count. Cases (n = 113) were classified as non-dysplastic BE (NDBE, n = 72), dysplastic BE (DBE, n = 11) and EAC (n = 30). RESULTS:NLR progressively increased across groups (NDBE, 1.92 ± 0.7; DBE, 2.92 ± 1.1; EAC 4.54 ± 2.9), with a significant correlation between its increasing value and the presence of dysplasia or neoplasia (r = 0.53, p 2.27 was able to diagnose EAC with 80% sensitivity and 71% specificity (area under the curve = 0.8). CONCLUSION:NLR correlates with advancing stages of BE progression, a finding that reinforces the role of immune imbalance in EAC carcinogenesis and suggests a possible use of this marker for risk stratification on surveillance strategies.