RESUMO
Objective To evaluate the clinical efficacy and toxicities of radical intensity-modulated radiotherapy (IMRT) combined with reduction in dose of prophylactic irradiation in the treatment of stage Ⅲ small cell lung cancer (SCLC).Methods A retrospective analysis was performed on the clinical data of 40 patients with stage Ⅲ SCLC who were admitted from January 2010 to August 2012.The prescribed dose was 60 Gy in 30 fractions to the primary gross tumor volume and was 54 Gy in 30 fractions to the planning target volume.All patients received induction chemotherapy,31 patients received adjuvant chemotherapy,and 22 patients received concurrent chemoradiotherapy;the platinum-based chemotherapy combined with etoposide or teniposide was adopted.Prophylactic cranial irradiation (25 Gy in 10 fractions) was administered to 17 patients.The short-term tumor response was evaluated by RECIST 1.0,and radiation-related toxicities were assessed by CTCAE 4.0.Overall survival (OS),local recurrence-free survival (LRFS),and progression-free survival (PFS) were calculated by Kaplan-Meier method.Results The short-term tumor response rate was 98％.The follow-up rate was 100％.Twenty-two patients were followed up for at least 2 years.The 1-and 2-year OS rates were 84％ and 48％,respectively; the LRFS rates were 89％ and 85％,respectively; the PFS rates were 61％ and 41％,respectively.Grade 0-1 radiation-related pneumonia was observed in 65％(26/40) of all patients,grade 2 in 25％ (10/40),grade 3 in 5％ (2/40),and grade 5 in 5％ (2/40).Grade 0-1 radiation-related esophagitis was observed in 53％ (21/40) of all patients,grade 2 in 43％ (17/40),and grade 3 in 5 ％ (2/40).Conclusions Preliminary results from this study suggested that IMRT combined with reduction in dose of prophylactic irradiation is safe and effective in patients with stage Ⅲ SCLC and is worth further evaluation in a large,prospective,randomized study.