Background Crizotinib has offered patients with non-small cell lung cancer (NSCLC) positive to ALK rearrangements a powerful therapeutical option. Despite the benefit of crizotinib, most patients develop resistance and progression with special emphasis on the central nervous system. Early identification of patients that will present brain metastases could potentially lead to additional interventions preventing relapse. The objective of this study was to identify patients who would present with future CNS relapse after initiation of
