P14.40 Incidence and risk factors identification for lung cancer brain metastasis

Abstract

Abstract BACKGROUND Lung Cancer (LC) is the most frequent malignant neoplasm around the world and it is one of the most frequent brain metastasis origins. The aim of the present work is to measure the incidence of brain metastasis in new-diagnosed LC patients and to identify the risk factors associated with its development. MATERIAL AND METHODS A retrospective observational study has been performed. Patients with new diagnosis of LC between January 2015 and December 2016 in our Center were included. Demographic, clinical and molecular variables were studied. Statistical analysis included a uni- and multivariate COX regression, survival analysis (log-rank test) and non-parametric two-independent sample tests. RESULTS Three-hundred and thirty-nine patients were diagnosed with LC in our Center between 2015 and 2016 (99 female; mean age: 66.1 years, SD=10.89). The incidence of brain metastasis was 16.25 cases each year since the initial diagnosis (19.2% of all patients). The risk of brain metastasis was increased in the first year after the diagnosis of LC (83.07% of cases). Patients with metastasis were younger than non-metastatic patients (64.0 vs. 66.6 years of age; p=.041). Small-cell lung carcinoma was the most frequent histological subtype associated with the development of metastasis (HR=2.267; p=.011), followed by the adenocarcinoma (HR=1.131; p=.624) and epidermoid (HR=.546; p=.067). No molecular factor (EGFR, ALK or p63 expression) was identified as risk factor. The overall survival of brain-metastatic patients was significantly lower than non-metastatic patients (167.0 vs. 273.0 days; p=.0002). CONCLUSION Brain metastasis are diagnosed in almost 20% of LC patients with, at least, three-years follow-up. Small-cell carcinoma subtype and younger patients were associated with a higher risk of brain metastasis, which is associated with a bad prognosis.