The Prognostic Factors And Treatment Strategy Of Brain Metastases From Small Cell Lung Cancer

Part1 Association between the timing of brain metastases and the prognosis of small cell lung cancer Objective To investigate the association between the timing of brain metastases and the prognosis of patients with small cell lung cancer(SCLC).Methods A retrospective analysis was performed in 131 patients with limited-stage SCLC firstly metastasized to the brain were admitted to our hospital from 2007 to 2015.According to the mid-BMFS,the patients were divided into early metastasis group(BMFS≤10,n=61)and late metastasis group(BMFS>10,n=70).The survival rates were analyzed using the Kaplan-Meier method.Between-group comparison was made by log-rank test.The Cox regression model was used for multivariate prognostic analysis.Results In all patients,the median overall survival(OS)time from the diagnosis of SCLC and 1-,and 2-OS rates were 22.5 months,87.3%,and 44.7%,respectively.Median OS time after brain metastases and 1-,2-OS rates were 9.3 months,39.3%,14.8%,respectively.There were no significant differences in median OS time after brain metastases between the early and late metastasis group(8.6 vs 9.3 months,P=0.695).Moreover,this factor did not significantly differ among patients without PCI or receiving difference therapy after brain metastases(P=0.240-0.731).Conclusions The timing of SCLC with brain metastases is significantly correlated with the OS rather than the OS after brain metastases.Therefore,prevention of brain metastases may be an effective approach to prolong the OS of patients with SCLC.Part2 Additional radiation boost to whole brain radiation therapy may improve the survival of patients with brain metastases in small cell lung cancerObjective The role of the dose escalation strategy in brain radiotherapy for small cell lung cancer(SCLC)patients with brain metastases(BMs)has not been identified.This study aims to determine whether the additional radiation boost to whole brain radiation therapy(WBRT)has beneficial effects on overall survival(OS)compared with WBRT-alone.Methods A total of 82 SCLC patients who were found to have BMs treated with WBRT plus a radiation boost(n=33)or WBRT-alone(n=49)from January 2008 to December 2015 were retrospectively analyzed.All patients were limited-stage(LS)SCLC at the time of the initial diagnosis,and none of them had extracranial metastases prior to detection of the BMs.The primary end point was OS.Results The median OS for the entire patients was 9.6 months and the 6-,12-and 24-months OS rates were 69.1%,42.2% and 12.8%,respectively.At baseline,the proportion of more than 3 BMs was significantly higher in WBRT group than in the WBRT plus boost group(p=0.0001).The median OS was significantly higher in WBRT plus boost group compared with WBRT-alone(13.4 vs.8.5 months,p=0.004).Further,the survival benefits still remained significance in WBRT plus boost group among patients with 1 to 3 BMs(13.4 vs.9.6 months;p=0.022).Conclusion Compared with WBRT-alone,the use of WBRT plus a radiation boost may prolong survival in SCLC patients with BMs.The dose escalation strategy in brain radiotherapy for selected BMs patients with SCLC should be considered.