Yen Allen, Tian Zhen, Hrycushko Brian, Albuquerque Kevin
Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
J Contemp Brachytherapy. 2018 Dec;10(6):510-515. doi: 10.5114/jcb.2018.80171. Epub 2018 Dec 28.
To determine risk factors for fistula formation after interstitial brachytherapy (ISBT) in patients with advanced gynecologic cancers.
We performed an Institutional Review Board (IRB) approved retrospective review of 44 patients treated with transperineal template-based ISBT from 2011 to 2017 at a major metropolitan county and university health system. All patients were treated with image-guided high-dose-rate ISBT. Statistical analysis was performed using the χ test to identify factors correlated with fistula formation. Survival and tumor control outcomes were calculated using Kaplan Meier analyses.
Patients had a mean age of 53 years (range, 28-81 years), a mean external beam dose of 43.1 Gy (range, 42.5-51.3 Gy), and a mean brachytherapy dose of 22.8 Gy (range, 21.3-30 Gy). Two of 44 patients had fistulas that could be definitively attributed to therapy for a fistula rate of 4.5%. Six additional patients (13.6%) developed fistula after treatment with associated recurrent disease but were included in the causality analysis. We analyzed patient tumor and treatment factors, and on univariate analyses we found that age ≥ 60 years, Hispanic ethnicity, bladder involvement, rectal D2 cc ≥ 70 Gy, and whether patients had post-radiation biopsies were predictors for fistula formation. The 1-year overall survival (OS), progression-free survival (PFS), and local control (LC) were 85%, 58.5%, and 76.9%, respectively, with a mean follow-up time 23 months (range, 4.0-68.8 months).
We identified factors that predict fistula formation in patients with advanced gynecologic tumors treated with ISBT. These factors can be used to stratify patients into a high-risk group, with potential for modification of brachytherapy planning to reduce their risk of fistula formation.
确定晚期妇科癌症患者接受组织间近距离放疗（ISBT）后发生瘘管形成的危险因素。
我们对2011年至2017年在一个主要大都市县和大学卫生系统接受经会阴模板引导下ISBT治疗的44例患者进行了一项经机构审查委员会（IRB）批准的回顾性研究。所有患者均接受图像引导的高剂量率ISBT治疗。采用χ检验进行统计分析，以确定与瘘管形成相关的因素。使用Kaplan Meier分析计算生存和肿瘤控制结果。
患者的平均年龄为53岁（范围28 - 81岁），外照射平均剂量为43.1 Gy（范围42.5 - 51.3 Gy），近距离放疗平均剂量为22.8 Gy（范围21.3 - 30 Gy）。44例患者中有2例发生瘘管，可明确归因于治疗，瘘管发生率为4.5%。另外6例患者（13.6%）在治疗后出现与复发性疾病相关的瘘管，但纳入因果关系分析。我们分析了患者的肿瘤和治疗因素，单因素分析发现年龄≥60岁、西班牙裔种族、膀胱受累、直肠D2 cc≥70 Gy以及患者是否进行放疗后活检是瘘管形成的预测因素。1年总生存率（OS）、无进展生存率（PFS）和局部控制率（LC）分别为85%、58.5%和76.9%，平均随访时间为23个月（范围4.0 - 68.8个月）。
我们确定了接受ISBT治疗的晚期妇科肿瘤患者发生瘘管形成的预测因素。这些因素可用于将患者分层为高危组，有可能调整近距离放疗计划以降低其瘘管形成风险。
