Adults with congenital lung malformations: A descriptive analysis of an underexplored population

Congenital lung malformations (CLM) comprise various developmental respiratory tract anomalies. Long-term outcomes in adulthood remain poorly defined because structured follow-up often ends after childhood. We aimed to determine the clinical, functional, and imaging characteristics of adults with CLM.

A retrospective study was carried out in adults with CLM followed up at our center. We assessed clinical characteristics, spirometry measures (FEV1, FVC, FEV1/FVC, and MMEF25-75), adult body plethysmography (TLC, RV, RV/TLC), and longitudinal volumetric quantification of CLM size on computed tomography (CT).

Thirty patients with CLM were included (14 diagnosed prenatally, 16 referred). Seventeen (57%) underwent surgery at a median age of 4 years (interquartile range 0-24.5). Adult symptoms occurred in 17 (57%) patients, with 86% of episodes managed conservatively. Two pulmonary malignancies (pleuropulmonary blastoma and adenocarcinoma) were identified in referrals, aged 24 and 31 respectively. Childhood spirometry showed reduced mean z-scores for FEV1 (-1.1 ± 1.6; p = 0.02) and FEV1/FVC (-1.3 ± 1.6; p = 0.01), as well as scores below the lower limit of normal (LLN; z-score < -1.64) for MMEF25-75 (-1.7 ± 1.4; p < 0.001). In adulthood, mean z-scores remained negative for all indices, with FEV1 (-1.7 ± 1.5; p < 0.001) and MMEF25-75 (-1.8 ± 1.3; p < 0.001) averaging below the LLN, while body plethysmography outcomes were mixed. Longitudinal volumetric CT analysis revealed that lesion size increased in 8 patients, fluctuated in 2, and decreased in 6.

Adults with CLM show persistent functional impairments and heterogeneous lesion progression on imaging. These findings mandate a standardized, multimodal surveillance protocol beyond childhood to proactively monitor for signs of late-onset disease progression.