The risk factors for brain metastases in patients with non-small cell lung cancer

Non-small cell lung cancer (NSCLC) with brain metastasis is the most common central nervous system malignancy, accounting for as much as 20% of every brain metastasis case (1). The incidence of brain metastasis has been increasing due to improvements in the control of systemic extra-cranial disease and the widespread availability of imaging modalities such as magnetic resonance imaging (MRI), which has increased the detection of subclinical disease (2-4).