WOFAPS 2025 8th World Congress of Pediatric Surgery

Kohei Kawaguchi ¹, Seiichiro Inoue ¹, Marino Nagara ², Yuki Muta ¹, Yuta Takeuchi ¹, Taisuke Hayashi ¹, Shuji Momose ², Akio Odaka ¹

¹ Department of Pediatric Surgery, Saitama Medical Center, Saitama Medical University
² Department of Pathology, Saitama Medical Center, Saitama Medical University

Background: Although the classical typing of congenital lung cyst by Stoker was based on the size of lung cyst, the revision of the clinical practice guidelines in Japan for congenital cystic lung diseases incorporated histopathological findings was published in 2022. According to the new classification, we tried retrospectively re-classification of our cases of congenital pulmonary airway malformation (CPAM) and compared them with corresponding imaging findings.Methods: We reviewed patients who surgically treated for CPAM between January 1, 2009, and March 31, 2024, at our center. Histopathological specimens were reclassified according to the new criteria and compared with prenatal ultrasound (US), fetal MRI, and neonatal CT findings.Results: A total of 17 patients were clinically diagnosed with CPAM during the 16-year period. Based on histopathology, 3 were classified as Type 1 and 14 as Type 2; no cases were classified as Type 3 or 4. All 17 cases were prenatally diagnosed via US. Fetal MRI was performed in 15 cases, of which 8 were interpreted as CPAM (Type 1: n=2, Type 2: n=1, unclassifiable: n=4, normal: n=7). Neonatal CT identified CPAM in 16 of the 17 cases. Discrepancies between MRI and CT findings were noted in 6 cases. Conclusion: Imaging-based classification still primarily depends on cyst size, which may not capture all relevant pathology. Some cases previously diagnosed as Type 2 required differentiation from bronchial atresia. The revised classification incorporating histopathology is essential for a more accurate understanding and etiological analysis of the disease.