Prognostic factors in non-small cell lung cancer metastatic to the brain

Abstract AIMS To identify prognostic factors significantly associated with overall survival in patients with non-small cell lung cancer (NSCLC) metastatic to the brain. To identify whether intracranial or extracranial factors had greater influence on overall survival in this cohort. METHOD Retrospective review of 21 patients from a single UK centre with NSCLC metastatic to the brain was undertaken. Hazard ratios were obtained from the Cox proportional hazards model, and survival curves plotted via the Kaplan-Meier method. RESULTS On univariate analysis, higher Karnofsky Performance Status (KPS) was significantly associated with improved overall survival compared to lower (HR 0.112; 95% CI 0.029 – 0.438) as was stable primary disease relative to progressive primary disease (HR 0.088; 95% CI 0.017 – 0.459). Surgical resection of primary disease was also associated with longer overall survival relative to no resection (HR 0.2713; 95% CI 0.075 – 0.980). Local treatment to brain metastases with either surgery or stereotactic radiosurgery prolonged overall survival relative to no local metastatic treatment (HR 0.1422; 95% CI 0.031 – 0.656). Notable variables not significantly associated with overall survival include number, size and location of metastases as markers of intracranial metastatic burden. CONCLUSIONS Primary disease activity (p = 0.004), KPS (p = 0.002), surgical resection of thoracic disease (p = 0.046) and treatment modality of brain metastasis (p = 0.012) were significant prognostic covariates in this cohort of 21 patients. Extracranial disease and patient factors appear to have greater prognostic significance than intracranial metastatic burden in this patient population.