Concordance of MRI, CT, and Surgical Pathology in Prenatally Diagnosed Lung Lesions.

Introduction: This study quantified the concordance of pre- and post-natal imaging and pathology diagnoses of fetal lung lesions.

Methods: Retrospective review of patients seen at a single Fetal Center from 2014-2024.

Results: 138 patients with prenatally diagnosed lung lesions were identified. Patients with an associated congenital diaphragmatic hernia (n=7) and patients with neither postnatal imaging nor surgical pathology (n=11) were excluded. 86.7% had postnatal imaging; of these, 79.8% had postnatal CT findings consistent with prenatal imaging. 68.3% had surgical resection at our institution. The remaining patients had surgery elsewhere or did not pursue resection of the lesion. Of those 82 patients, 90.2% had a pathologic diagnosis concordant with their prenatal MRI and 97.1% had a pathologic diagnosis concordant with postnatal CT. The most common case of discordance between pre- and post-natal imaging was bronchial atresia (71.4%, 15/21) which was originally called a CPAM/BPS/hybrid lesion on prenatal imaging. The most striking case of discordance between imaging and pathology was a pleuropulmonary blastoma initially called a CPAM on prenatal MRI.

Conclusion: Congenital lung lesions may evolve during pregnancy, highlighting the value of postnatal imaging to further characterize the lesions and assess the appropriateness of patients for surgical resection.