Résumé
Objective:To evaluate the effects of simultaneous integrated boost intensity-modulated radical radiotherapy (SIB-IMRT) on the long-term prognosis of patients with cervical and upper thoracic esophageal cancer.Methods:From January 2011 to December 2014, a retrospective analysis was performed in 172 patients with cervical and upper thoracic esophageal cancer who were eligible for IMRT. First, the prognosis of all the patients was evaluated using single factor and multivariate analyses. According to the different irradiation method of the patients, the patients were divided into two groups, one of which received conventional IMRT (C-IMRT) and the other of which received SIB-IMRT. Propensity score matching (PSM) analysis was applied to match the two groups of patients and to determine the treatment efficacy of patients after PSM, prognostic factors, failure modes, and side effects. SPSS19.0 statistical software was used to conduct statistical analysis.Results:The median overall survival (OS) and progression-free survival (PFS) times of all the patients were 30 months and 20 months, respectively. The fact whether the surrounding tissues and organs of esophageal lesions were invaded, clinical node staging (cN staging), chemotherapy, and GTV-maximum transverse diameter were observed to be independent influencing factors of OS and PFS in all the patients ( P<0.001, P=0.013, 0.005, 0.002; P<0.001, P=0.017, 0.034, 0.002). In addition, the independent influencing factors of PFS showed short-term efficacy ( P=0.036). After PSM, there were 54 patients in each of the two groups. The result of multivariate analysis showed that the fact whether the surrounding tissues and organs of esophageal lesions were invaded, cN staging, cTNM staging, prescribed dose, GTV-maximum transverse diameter, and irradiation method were independent factors affecting the OS ( P<0.001, P=0.008, 0.014, 0.021, 0.010, 0.008). Similarly, the fact whether the surrounding tissues and organs of esophageal lesions were invaded, cN staging, and GTV-maximum transverse diameter were observed to be independent factors that affect the PFS of patients ( P<0.001, P=0.044, 0.013). The difference in the total failure rate (70.4% vs. 50.0%) and the local regional recurrence rate (61.1% vs. 31.5%) between the C-IMRT and SIB-IMRT groups after treatment was significant ( χ2=4.68, 9.53, P=0.031, 0.002). The incidence of radiation pneumonitis of grade ≥ 1 in the C-IMRT group was significantly higher than that of the SIB-IMRT group ( χ2=6.16, P=0.046), whereas the leukocyte suppression of grade ≥ 2 in the C-IMRT group was significantly lower than that in the SIB-IMRT group ( χ2=12.77, P=0.005). Conclusions:As shown by the result of this study, compared with C-IMRT, SIB-IMRT can improve the OS of patients with cervical and upper thoracic esophageal cancer to a certain extent. Whether SIB-IMRT can improve the PFS of patients requires further research.