Analysis Of Related Factors Of Brain Metastasis After Treatment Of Limited Small Cell Lung Cancer

Objective:Retrospectively analyzing the incidence of brain metastasis in patients with limited-stage small-cell lung cancer(LS-SCLC)after treatment,and its correlation with treatment methods and therapeutic efficacy,to explore risk factors of brain metastasis and the methods to reduce the incidence of brain metastasis.Methods:All subjects enrolled in the study were screened patients by inclusion criteria and exclusion criteria,and they were examined by chest and abdomen CT,craniocerebral MRI and whole body bone scan after radiotherapy and chemotherapy.According to RECIST 1.1 for short-term efficacy evaluation,the patients included in the study were divided into four different states as follows: complete remission(CR),partial remission(PR),stability(SR)and disease progression(DR).Follow-up of primary thoracic lesions and brain metastases were continued and recorded and the possible influencing factors were grouped and analyzed to explore their correlation with brain metastasis.Statistical calculations were performed using SPSS,version 23.The Kaplan-Meier test in survival analysis was used for univariate analysis.Log-rank test was used to analyze the differences between groups,and Cox regression was used to explore the independent influencing factors of brain metastasis.Results:1.In this study,79 patients with LS-SCLC were enrolled,including concurrent radiotherapy and chemotherapy(n=23 cases),sequential radiotherapy and chemotherapy(n=13 cases),and simple chemotherapy((n=43 cases).There were 40 patients with complete or partial remission after treatment and the overall response rate(CR+PR)was 50.63%.Twenty patients received prophylactic brain irradiation after tumor remission.The follow-up period was 6-65 months,with a median of 19 months.During the follow-up period,31 patients in all subjects with LS-SCLC had brain metastasis,the rate of brain metastasis was 39.24%,and the median survival time without brain metastasis was 15 months.Statistical analysis of brain metastasis rates of all patients showed that the brain metastasis rates of one year,two years,three years and five years were 20.25%,32.91%,37.97% and 39.24%,respectively.The median survival time of 79 LS-SCLC patients was 19 months.The overall survival(OS)of all included patients was 81.00% in one year,36.70% in two years,15.20% in three years and 7.10% in five years.2.Univariate analysis showed that the following factors,including ratio of neutrophil to lymphocyte(NLR),the dose of chest radiotherapy,the treatment method,the curative effect and prophylactic cranial irradiation(PCI),had statistically significant influence on brain metastasis(all P < 0.05)and no significant differences were found in Gender,age,ECOG score,smoking history,NSE,chemotherapy cycle and other factors.The influence of brain metastasis on OS was statistically significant(P=0.001).3.Multivariate analysis showed that NLR(P=0.021)and PCI(P=0.014)were independent factors of brain metastasis for LS-SCLC after treatment.Conclusion:1.Chest concurrent radiotherapy and chemotherapy,dose(> 54 Gy),or remission of curative effect or PCI treatment can significantly reduce the risk of brain metastasis In LS-SCLC patients.2.The level of NLR before initial treatment and PCI treatment were independent influencing factors of brain metastasis for LS-SCLC after treatment.