The following clinicopathologic features are peculiar to ALK-rearranged patients: young age at diagnosis (a median of 50 years), female, non-smokers/light smokers, adenocarcinoma histology with distinctive morphologic patterns such as cribriform and solid signet ring, expression of thyroid transcription factor 1, a tendency to metastasize to the pleura or pericardium, and particularly to the central nervous system [7]. This evidence concerns the gene ALK and adenocarcinoma.