Analysis of factors influencing the distribution of brain metastases from lung cancer: A retrospective study

Abstract BACKGROUND The distribution of brain metastases (BMs) in patients with lung cancer may be related to primary tumor and cerebral small vascular diseases (CSVDs), but it is not clear which one or more factors affect the distribution. PURPOSE To investigate the effects of primary tumor-related factors and CSVDs on the distribution of BMs (the number of BMs in each brain region) in patients with lung cancer. METHODS A total of 5,788 lesions in 823 patients with BMs from lung cancer were enrolled. The numbers of BMs and CSVDs in 15 brain regions were determined. CSVDs included recent small subcortical infarcts (RSSIs), perivascular spaces, and lacunes of presumed vascular origin (LPVOs). We collected the number of CSVDs, primary tumor-related factors (including clinical and imaging features) and other potential influencing factors (including the patient's general condition and treatment). We used univariate and multivariate linear regression models to analyze the influence of the above factors on the number of BMs in 15 brain regions. In addition, we performed subgroup analyses of all patients with adenocarcinoma (AD), male patients with AD, female patients with AD, and patients with small cell lung cancer (SCLC). RESULTS Univariate linear regression analyses showed that bone metastasis, adrenal metastasis, RSSIs, and LPVOs greatly affected the number of BMs in over half of the examined brain regions. Multivariate linear regression analyses showed LPVOs independently affected the number of BMs in nine brain regions. In the subgroup analyses of all AD, male AD, female AD, and SCLC, LPVOs independently affected the number of BMs in eight, seven, and nine brain regions, respectively. CONCLUSIONS The distribution of BMs is mainly affected by LPVOs, while primary tumor-related factors have less influence on the distribution of BMs.