The Clinical Observation On Whole-brain Radiotherapy Combined With Sequential Integrated Boost For Non-small Cell Lung Cancer With Brain Metastases

Objective: To retrospectively analyze the efficacy of whole-brain radiotherapy(WBRT)combined with sequential integrated boost(SEB)for brain metastases.Methods: A total of 170 patients who received WBRT or WBRT combined with SEB were included in the study.The dose of WBRT was 30-40Gy/2Gy/15-20 f,and the total dose was 50-66Gy/2Gy/25-33 f.The primary end point was overall survival(OS).The secondary end point was short-term efficacy.SPSS22.0 statistical software was used to analyze the data,and Fisher's test or ?2 test was used to compare the rate or proportion.Kaplan-Meier method was used for survival analysis,and Cox regression method was used for univariate and multivariate analysis.P < 0.05 was considered statistically significant.Results: The median age was 56 years old.The time of follow-up ranged from 1 month to 94 months(median follow-up time was 7 months),and WBRT combined with SEB(group B)prolonged the median OS significantly compared with WBRT(group A)(10 months vs.5 months;HR=0.490;95%CI,0.348~0.691;P<0.001).Univariate analysis indicated that age,KPS score,RPA classification,GPA score,T stage and N stage of lung cancer,extracranial metastases,the condition of extracranial lesions(including primary tumor)and the method of radiotherapy affect the survival significantly.Further multivariate analysis showed that RPA classification,the N stage of lung cancer,the condition of extracranial lesions and the radiotherapy regimen for brain metastases were independent prognostic factors.The ORR and DCR of group A were 37.5% and 77.5%,respectively.In group B,ORR was 65.8% and DCR was 89.9%.There was significant difference in the short-term efficacy between the two groups(P=0.331).Compared with group A,patients in group B had significant higher ORR(P=0.006),but the difference of DCR between two groups was not statistically significant(P=0.095).Conclusion: The RPA classification,N stage of lung cancer,condition of extracranial lesions(including primary tumor),radiotherapy regimen may predict prognosis of patients.WBRT combined with SEB is more efficient for brain metastases compared with WBRT alone.