Fig. 1: Congenital pulmonary airway malformations with mucinous cell clusters (MCCs) contain KRAS codon 12 mutations within MCCs and throughout the lesion.

MCCs from separate blocks (A), lesional tissue without MCCs (B), and normal lung tissue (B) were macrodissected from 20 µm thick FFPE tissue sections. C Within each patient, the same KRAS codon 12 mutation was found throughout the lesion, including in each MCC. Adjacent uninvolved lung always had wild type KRAS sequence. *p < 0.05, binomial distribution.