Therapeutic evaluation between coventional fraction radiotherapy and intensity modulated radiation therapy combined with concurrent chemotherapy for esophageal carcinoma / 肿瘤研究与临床

ABSTRACT

Objective To evaluate the curative effect between conventional fraction radiotherapy (CFRT) and intensity modulated radiation therapy (IMRT) combined with concurrent chemotherapy for unresectable esophageal carcinoma.Methods 144 patients were enrolled into this study.They were divided into CFRT group and IMRT group.CFRT group (60 cases)irradiation field encompassed primary lesion and mediastinal lymph drainage regin.Neck and thoracic upper segment cases were made front thorax T field irradiation first,DT 36 Gy/18 f,followed by two front oblique field made Iso-central irradiation,field width was 4.5-5.0 cm,gantry angle 50°-60°,wedge filter 30°,DT added to 66 Gy.For thorax middle or lower segment patients,field width was 6.0-6.5 cm,field length was that the tumor upper and lower each extended 3.0-5.0 cm,vertically irradiated in thoracic front and at the back,after DT 36 Gy/18 f,changed to two back ablique field,made Iso-central irradiation,DT added to 66 Gy.IMRT group (84 cases)GTV was esophageal primary lesion and metastasis lymph node (GTVnd);CTV included GTV,GTVnd and mediastinal lymph drainage region,at GTV around all was widened 0.8-1.0 cm,its upper and lower each extended 3.0-5.0 cm;PTV were in the basis of CTV,all were widened 0.5 cm again.With ≥95 ％ isodose curve covering the PTV and the target dose was prescribed to PTV 60-64 Gy/30-32 f.Organ at risk (OAR)both lungs V20≤30 ％,spinal cord ≤45 Gy/6 weeks,heart V30≤40 ％.Chemotherapy of two groups was same,DDP 25-30 mg/m2 × 3-5 days,5-Fu 450-500 mg/m2 × 5 days civ,28 days were one period,total 2 period,after 1-3 months,strengthen chemotherapy 3-4 period.Results Leucopenia and radiation-induced esophagitis as shown by the WHO staging system were the most common acute toxicities,but were mainly grade 1 or 2.The incidence rate of leucopenia and radiation-induced esophagitis in CFRT group were 78.3 ％ (47/60) and 83.3 ％ (50/60),IMRT group were 82.1％ (69/84) and 79.8 ％ (67/84).After symptomatic treatment,all patients completed the planner treatment.During radiotherapy and after treatment,the patients showed grade 1-2 radiation-induced pneumonitis,CFRT group were 36.7 ％ (22/60),but IMRT group were only 9.5 ％ (8/84) (x2 =9.99,P ＜ 0.01).In CFRT group and IMRT group,the 1-,3-,5-year survival rates were 75.0 ％ (45/60),36.7 ％ (22/60),20.0 ％ (17/84) and 79.8 ％ (67/84),35.7 ％ (30/84),21.4 ％ (18/84),respectively.Conclusion The overall response and 5-year survival rates of CFRT and IMRT combined with concurrent chemotherapy are similar,however,the incidence of grade 1-2 radiation-induced pneumonitis of IMRT is low,which indicates that IMRT can reduce the lungs irradiational volume and dose.