ALK and neoplasm: We found that the stage distribution in NSCLC patients with ALK rearrangements were all very similar, i.e. largest number in stage I and none or very few in stage IV, between our study and 4 published reports [21,24,25,27], The reason why it was not significantly associated with the tumor stage was that patients without ALK rearrangements also had highest patient number in stage I and lowest in stage IV in all of these 5 studies (only 2 to 14 patients in stage IV).