The Survival Outcome And Prognostic Factors Of Brain Oligometastatic Non-small Cell Lung Cancer Patients

Background and objective: Non-small cell lung cancer patients with brain metastasis have poor prognosis,while patients with brain oligometastasis can benefit from local treatment.The purpose of this study was to investigate the clinical characteristics of patients with brain oligometastasis of NSCLC,to analyze prognostic factors.Method: A total of 96 NSCLC patients with brain metastases admitted to the first affiliated hospital of Dalian Medical University from January 2004 to December 2017 were collected.49 patients with brain oligometastases and 46 patients without brain oligometastases were retrospectively included.Gender,age,smoking status,location,number,maximum volume of brain oligometastases,pathological type,treatment method of brain oligometastases,simultaneous metastasis vs.heterogeneous metastasis,location of primary focus,treatment of primary focus,TNM staging of primary focus were collected.Overall survival(OS)was used as an indicator to compare the differences in clinical characteristics between patients in the oligometastatic group and those in the non-oligometastatic group,and to analyze the influence of clinical characteristics on prognosis in the oligometastatic subgroup.Results: 1.In the comparison of clinical features between the patients with brain oligometastases of NSCLC and those with non-oligometastases,there were 24 patients(49.0%)with primary N0 stage in the oligometastastic group and 8 patients(17.4%)in the non-oligometastastic group,and the difference was statistically significant(P<0.05).There were no significant differences in age,gender,smoking history,pathological type,location of primary lesion,radical resection of primary lesion and T and N stages of primary lesion.2.The median overall survival(MST)was 25.7 months and 11.0 months,respectively,in NSCLC patients with brain oligometastases and those with non-oligometastases.OS was significantly prolonged in patients with oligometastases(P<0.001).MST of patients in the NSCLC brain oligometastases group was 25.7 months,and MST was 11.0 months in patients with non-oligometastases.Survival time of patients with brain oligometastases was significantly prolonged(p<0.001).3.In the subgroup of brain oligometastases of NSCLC,univariate analysis showed that non-smokers had better MST than smokers(29.9 months vs.18.7 months,P=0.030).MST of patients with radical primary resection was better than those without radical resection(40.8 months vs.9.6 months,P<0.001).MST in primary T1-2 stage was superior to T3-4 stage(32.7 months vs.9.1 months,P=0.002).MST of primary tumor at N0 stage was superior to that of patients at N1-3 stage(41.6 months vs.14.4 months,P=0.002).All the above were statistically different.Age,gender,pathological type,brain metastasis site,number,maximum diameter,primary lesion site,occurrence pattern of brain metastasis(simultaneous metastasis/heterotopic metastasis),treatment method of brain metastasis,etc.were not related to OS.4.In the subgroup of brain oligometastases of NSCLC,multivariate analysis showed that pathological type(P=0.05,HR=0.409)and radical resection of the primary lesion(P=0.001,HR=8.629)were independent prognostic factors for patients with brain oligometastases of NSCLC.Patients with adenocarcinoma and primary radical resection of NSCLC with oligometastases had better prognosis.5.In the subgroup of brain oligometastases of NSCLC receiving local treatment,39 patients received radical surgery for brain metastasis(MST 21.6 months),and 5 patients received stereotactic radiotherapy.Since none of the 5 patients reached the end event,statistical analysis could not be performed,but OS in patients receiving stereotactic radiotherapy has a extension tendency than that in patients undergoing radical surgery.6.In the subgroup of brain oligometastases of NSCLC receiving local treatment,univariate analysis showed that patients with radical resection of the primary lesion had better MST than those without radical resection(33.5 months vs.9.6 months,P<0.001).MST in patients with primary T1-2 stage was superior to those with T3-4 stage(32.7 months vs.9.1 months,P=0.004).MST of primary tumor in N0 stage was better than that in N1-3 stage(41.6 months vs.14.4 months,P=0.003).All the above were statistically different.Age,gender,smoking history,location of brain metastasis,number,maximum diameter,pathological type,location of primary lesion and other factors were not related to OS.7.In the subgroup of brain oligometastatic NSCLC patients receiving local treatment,multivariate analysis showed that the maximum diameter of the metastatic lesion(P=0.050,HR=2.387),pathological type(P=0.039,HR=2.648)and radical resection of the primary lesion(P=0.003,HR=7.157)were independent prognostic factors.NSCLC patients with the longest diameter of metastatic lesion < 3cm,adenocarcinoma and radical resection of primary lesion had better prognosis.8.Radical primary resection(p=0.002)and the primary lesion in the T1-2 phase(p=0.020)were associated with longer survival time(? 24 monthes)in oligometastastic patients with NSCLC.Conclusions: 1.Among the patients with brain oligometastases of NSCLC,the majority of the patients with primary lesions were in the N0 stage.2.OS of NSCLC patients with brain oligonmetastases is better than that of patients with non-oligometastases,with a better prognosis.3.Among the patients with oligometastases of NSCLC,those with no history of smoking,radical primary resection,primary T1-2 stage and N0 stage had longer OS.Pathological type and radical resection of primary lesions were independent prognostic factors,among which adenocarcinoma and oligometastatic NSCLC patients with radical resection of primary lesions had better prognosis.4.Among the patients receiving local treatment for brain oligometastases of NSCLC,OS of those receiving stereotactic radiotherapy showed a longer trend than those receiving radical surgery.5.Among the patients receiving local treatment for brain oligometastases of NSCLC,patients with primary radical resection,primary T1-2 stage and N0 stage had longer OS.The maximum diameter of the metastatic lesion,pathological type and radical resection of the primary lesion were independent prognostic factors.Among them,patients with the maximum diameter of the metastatic lesion <3cm,adenocarcinoma and radical resection of the primary lesion had better prognosis.6.Surgical treatment of the primary lesion,the primary lesion at the stage of T1-T2,was associated with long survival time(OS ?24 months)in NSCLC patients with brain oligometastases.