Congenital Pulmonary Airway Malformation Type 1 With KRAS Mutation: A Case Report and Literature Review.

Congenital pulmonary airway malformation (CPAM) is a rare developmental anomaly of the fetal lung characterized by abnormal branching morphogenesis, resulting in cystic and/or solid masses within the pulmonary parenchyma. These cysts can range in size and symptoms: from small and asymptomatic to large and clinically evident. CPAM is typically identified during prenatal ultrasonography as an abnormal lung mass, predominantly involving a single pulmonary lobe. We herein describe a case of a fetus diagnosed with CPAMs type 1 harboring a KRAS pathogenic variant.