ALK and laryngotracheoesophageal cleft: The frequency of neoplastic nuclei by ALK FISH tended to be positively correlated with progression-free survival (PFS) and associated with initial ALK inhibitor response in patients with ALK-rearranged Ad-LC (R2 = 0.300: p = 0.081); however, only a weak association was observed in patients with ALK-rearranged Sq-LC (p = 0.284), although the number of patients was too low for statistical analysis (Figure 3B).