图像融合技术下胸段食管鳞癌同步放化疗后复发模式及剂量学研究

Image fusion-based recurrence patterns and dosimetry after concurrent chemoradiotherapy for thoracic esophageal squamous cell carcinoma

目的应用图像融合技术分析胸段食管鳞癌同步放化疗后食管病变局部复发部位的分布特点,并探讨局部复发的影响因素及其与剂量学指标的关系。方法回顾分析2016年至2019年于河北医科大学第四医院行根治性同步放化疗的209例胸段食管鳞癌患者资料。将确诊为食管病变局部复发患者的CT图像与原计划CT图像通过图像配准软件进行融合比对,明确复发部位。对食管复发组(81例)及局部无复发组(128例)患者的临床资料进行1∶1倾向评分匹配,比较匹配后两组患者(各62例)治疗计划中各剂量、体积参数的差异。采用Kaplan-Meier法及Cox回归模型对总生存(OS)、无进展生存(PFS)、局部无复发生存(RFS)的影响因素进行单因素及多因素分析。结果全组1、3、5年OS率分别为80.9%、42.6%、33.0%,PFS率分别为67.9%、34.0%、27.9%,RFS率分别为71.3%、39.2%、30.5%。T分期、N分期、放疗剂量为食管癌患者OS、PFS及RFS的独立影响因素(HR=1.42~1.87,P<0.05)。68例放疗后食管病变局部复发的患者中,62例(91.2%)复发位于GTV内。食管复发组患者的剂量参数(GTV、CTV)D_(95%)、(GTV、CTV、PTV)D_(50%)以及体积参数(GTV、CTV、PTV)V_(60)均显著低于局部无复发组(t=1.90~2.15,P<0.05)。结论胸段食管癌根治性放化疗后局部复发主要发生在GTV内;提高放疗剂量可能存在生存获益,放疗计划各靶体积D_(50%)受量情况可能与局部复发有关,需要进一步深入探讨。

Objective To analyze the local recurrence patterns after concurrent chemoradiotherapy(CCRT)for thoracic esophageal squamous cell carcinoma(ESCC)through image fusion,and to explore the risk factors of local recurrence and its relationships with dosimetric indices.Methods A retrospective analysis was conducted for 209 thoracic ESCC patients who received radical CCRT in Fourth Hospital of Hebei Medical University during 2016-2019.For the patients diagnosed as the local recurrence of esophageal lesions,their CT images were fused with the original planning CT images using image registration software to identify the recurrence sites.Through 1∶1 propensity score matching(PSM)of the clinal data of patients with local recurrence(the recurrence group,n_(before)=81,n_(after)=62)and those without local recurrence(therecurrence-free group,n_(before)=128,n_(after)=62),the dose and volume parameters of the treatment plans for the two groups were compared.Univariate and multivariate analyses were conducted using the Kaplan-Meier method and the Cox regression model to analyze the factors affecting the overall survival(OS),progressionfree survival(PFS),and recurrence-free survival(RFS).Results All patients had 1-,3-,and 5-year OS rates of 80.9%,42.6%,and 33.0%,respectively,1-,3-,and 5-year PFS rates of 67.9%,34.0%,and 27.9%,respectively,and 1-,3-,and 5-year RFS rates of 71.3%,39.2%,and 30.5%,respectively.T stage,N stage,and radiation dose were independent prognostic factors for the OS,PFS,and RFS(HR=1.42-1.87,P<0.05)of the patients,respectively.Among 68 patients with local recurrence,62 cases(91.2%)suffered recurrence within the gross tumor volume(GTV).The dose and volume parameters of patients with local recurrence,such as GTV-D_(95%),clinical target volume(CTV)-D_(95%),GTV-D_(50%),CTVD_(50%),and planning target volume(PTV)-D_(50%),GTV-V_(60%),CTV-V_(60%),and PTV-V_(60%),were significantly lower than those of patients free from the local recurrence(t=1.90-2.15,P<0.05).Conclusions Local recurrence of patients with thoracic ESCC after radical CCRT occurs mainly within the GTV.Increasing radiation doses may contribute to their survival benefits.The D_(50%)for each target volume in the radiotherapy plan may be related to local recurrence,and it is necessary to conduct further research.