Clinical effect of thoracic radiotherapy and prophylactic cranial irradiation in patients with extensive small cell lung cancer after chemotherapy:a phase II trial

Objective To investigate the efficacy and safety of thoracic radiotherapy (TR) and prophylactic cranial irradiation (PCI) in patients with extensive small cell lung cancer (SCLC) who show response to chemotherapy.Methods From July 2010 to March 2012,30 patients with a pathological or cytological diagnosis of extensive SCLC who showed response to 4-6 cycles of chemotherapy with carboplatin plus etoposide or chemotherapy with cisplatin plus etoposide were included in the study.The median age of patients was 57 years (range,40-71 years).All the patients received TR (50---60 Gy) and PCI (25Gy).The short-term efficacy was assessed by RECIST 1.1,and the toxicities were evaluated according to CTCAE 3.0 and RTOG radiation morbidity scoring criteria.Results Twenty-nine of the 30 patients completed the TR and PCI.Of these patients,13％ showed complete remission,27％ showed partial remission,and 60％ showed stable disease,and the disease control rate was 100％.Progression was seen in 16 patients after effective treatment,including 1 patients with locoregional failure (LRF) alone and 15patients with distant failure (DF) (9 patients with DF alone and 6 patients with locoregional and distant metastases,4 patients with brain metastasis).The follow-up rate was 100％.The 1-year LRF rate and DF rate were 24％ and 51％,respectively.The 1-year overall survival rate and disease-free survival rate were 71％ and 37％,respectively.The acute toxicities included grade ≥2 hematological toxicity and grade ≥ 2radiation esophagitis,which occurred in 33％ and 13％ of all patients.Conclusions TR and PCI have good short-term efficacy and safety in extensive SCLC patients with response to chemotherapy and can reduce brain metastases and local recurrence.However,further study is needed with a larger sample. Key words: Carcinoma, small cell lung/chemotherapy;  Carcinoma, small cell lung/chemotherapy/radiotherapy;  Prophylactic cranial irradiation;  Phase Ⅱ clinical trail