Effect Of WBR Or Not And Different Dose On Survival Of LC Patients With BM

Objective: To evaluate the effect of WBRT or not and different dose on overall survival(OS)and intracranial progression free survival(PFS)of lung cancer(LC)patients with brain metastasis(BM).Methods:a retrospective analysis was performed on LC patients with BM from2013 to 2015.Follow up date to December 1,2016 or date of death or loss.According to the medical records,in accordance with the radiotherapy(RT)or not and different doses:(1)WBRT: No,30 Gy,30-39 Gy and above 40Gy;(2)local boost total does: No,50 Gy,50-59 Gy and 60Gy;(3)stereotactic radiosurgery/stereotactic radiotherapy(SRS/SRT): yes or no.The main variable was WBRT or not and different doses,the results were OS and PFS.Covariates included:(1)general situation: sex,age,KPS score;(2)the BM:brainstem and meningeal metastasis,BM symptoms,BM site number,cardiovascular disease(CVD),LC days at BM,BM partial or entire surgey,chemotherapy,targeted therapy;(3)the LC: LC pathology,LC stage,LC resedual or entire surgey,EGFR and ALK gene detection,chemotherapy and targeted therapy.K-M curve was used to calculate the survival time and Log-Rank test to analyze the correlation between OS,PFS and many factors,and the COX proportional hazards model was used to calculate the hazard ratio(HR)and the corresponding P value,P <0.05 was statistically significant.SAS 9.20 was used for statistical processing.Result:1 Population data The total number of cases in this study were 828 cases when the average age was 59.4 years(range 22-90).Groups by age: <50,50-59 and over 60 years.Women were 322 cases(38.9%),KPS score over 90 were 335 cases(40.5%).In the BM: groups by WBRT or not and different doses: No group were454 cases(54.8%),30 Gy group were 43 cases(5.2%),30-39 Gy group were134 cases(16.2%),above 40 Gy were 197 cases(23.8%).Groups by local boost total does: No group were 567 cases(68.5%),<50Gy were cases(4.7%),50-59 Gy were 137 cases(16.5%),above 60 Gy were 85 cases(10.3%),SRS/SRT were 25 cases(3%).LC days at BM over 30 days were 431 cases(52.1%),the number of BM site over 2 were 514 cases(62.1%),brainstem and meningeal metastasis were 24 cases(2.9%),43 cases(5.2%),BM symptoms were 463 cases(55.9%),extracranial metastasis were 559 cases(67.5%),CVD were 358 cases(43.2%),BM surgery were 41 cases(5%),targeted therapy and chemotherapy were 178 cases(21.5%),433 cases(52.3%).In the LC,SCLC(small cell lung cancer)were 166 cases(20%),LC first diagnosed as stage ? were 501 cases(60.5%).LC resedual or entire surgey were 129 cases(15.6%),targeted therapy and chemotherapy were 199 cases(24%)and 620 cases(74.9%),257 cases(31%)underwent RT.2 Analysis of groups by WBRT or not and different doses Grouped by WBRT or not and different doses by chi-square test,KPS score,BM symptoms,brain metastasis,extracranial metastasis,LC days at BM,chemotherapy after BM,local boost total does,SRS/ SRT,LC stage,EGFR gene detection,LC surgey,chemotherapy and RT on lung,had statistical difference(P<0.05);gender,brainstem and meningeal metastasis,BM site number,CVD,BM surgey and targeted therapy,ALK gene detection and targeted therapy before LC,had no significant difference(P>0.05).3 OS analysis of groups by WBRT or not and different doses The median OS of the population was 9.0 months(30 days).The median OS of groups were respectively at 7.1,4.8,10.9 and 11.8 months.In univariate COX survival analysis,compared with No WBRT group,the other three groups of OS HR(95%CI)were 1.635(1.163-2.300),0.680(0.543-0.853)and 0.600(0.492-0.732),P=0.005,<0.001and<0.001,there was significant difference.The results showed that: compared with No WBRT group,30-39 Gy and above 40 Gy groups have a lower risk,and is a useful prognostic factor,but no significant difference between the two groups.In the COX multivariate survival analysis,compared with No WBRT group,the other three groups of OS HR(95%CI)were 1.268(0.881-1.826),0.638(0.447-0.854)and 0.561(0.441-0.715),P values were 0.201,0.003 and0.001.The results showed that: compared with No WBRT group,the <30Gy group was no significant difference,30-39 Gy and 40 Gy groups were still statistically significant,and had a lower risk,and was a useful prognostic factor,but no significant differences between the two groups.Compared with No WBRT group,There was no statistical difference,and the reason was unknown,which may be the reason for the sample selection bias or the sharp decline of the general state of patients.4 PFS analysis of groups by WBRT or not and different doses The median PFS was 8 months,according to WBRT or not and different doses,the median PFS of was 5.9,4.3,11.1,and 11.2 months,respectively.In univariate COX survival analysis,compared with No WBRT group,the other three groups of PFS HR(95%CI)were 1.705(1.213-2.397),0.639(0.513-0.796)and 0.614(0.508-0.743),P=0.002,<0.001 and <0.001.The results showed that: compared with No WBRT group,other three groups were statistically significant,30-39 Gy and 40 Gy groups had a lower risk and that may be a beneficial factor in local control,but no significant differences between the two groups.In the COX multivariate survival analysis,compared with No WBRT group,other three groups of PFS HR(95%CI)were 1.357(0.947-1.945),0.618(0.464-0.822)and 0.604(0.476-0.765),P=0.096,< 0.001 and < 0.001.The results showed that: compared with No WBRT group group,the <30Gy group was no significant difference,30-39 Gy and 40 Gy groups had significant difference,and had a lower risk,suggesting independent beneficial factors in local control,but no significant difference between the two groups.5 Analysis of the influence of non radiotherapy factors on OS and PFS By COX multivariate survival analysis,in OS,local boost total does,SRS/SRT,female,high KPS score,single BM site,shorter BM history,and targeted therapy,are useful prognostic factors(P < 0.05);in PFS,women,high KPS score,single BM site,no extracranial metastases,and targeted therapy,may be beneficial factor in local contral(P < 0.05).Conclusion:1 WBRT can improve OS and PFS for LC patients with BM.2 In OS and PFS,?40 Gy did not provide more benefit.3 In OS,useful prognostic factors also include local boost does,the use of SRS/SRT,female,high KPS score,single BM site,shorter BM history,targeted therapy and chemotherapy;in PFS,female,high KPS score,single BM site,no extracranial metastasis,targeted therapy and chemotherapy,may be beneficial factors in local control.