Background: Brain metastases (BM) remain a significant problem in NSCLC patients. The reports of factors associated with BM are varied in previous studies including age, histology subtypes, and oncogenic driver alterations.

Objective: To determine the prevalence and factors associated with BM in advanced NSCLC patients and to analyze the median overall survival (OS) of the patients that had BM at the time of diagnosis of NSCLC and during the course of the disease.

Materials and Methods: The medical records of 552 advanced NSCLC patients between 2011 and 2018 were reviewed. The prevalence of BM was calculated by descriptive statistics. Factors associated with BM were analyzed by using univariate and multivariate analyses. Kaplan-Meier methods were used to analyze the median OS of NSCLC patients with BM.

Results: Between January 2011 and December 2018, of the 552 patients newly diagnosed with advanced NSCLC, there were 164 patients who had BM. The prevalence of BM was 29.7%. In multivariate analysis, younger age (adjusted odd ratio [OR] 1.547, 95% confidence interval [CI] 1.049 to 2.280), and adenocarcinoma subtype (adjusted OR 2.529, 95% CI 1.262 to 5.067) were significantly associated with BM. The median OS of patients who had BM at time of advanced NSCLC diagnosis was 7.5 months (95% CI 6.4 to 8.5) and the median OS of patients who had BM during the course of disease was 14.4 months (95% CI 12.2 to 16.5).

Conclusion: One-third of the advanced NSCLC patients developed BM. Younger age and adenocarcinoma subtype were associated with BM. Patients who had BM during the course of diseases had better survival outcomes compared to those who had BM at the time of advanced NSCLC diagnosis.

Keywords: Advanced NSCLC; Brain metastases

DOI: doi.org/10.35755/jmedassocthai.2021.12.12469

Received 14 June 2021 | Revised 3 September 2021 | Accepted 3 September 2021