Computed tomography (CT)-based classification and management pathways for hybrid lesions in children: a comparative analysis of congenital pulmonary airway malformation (CPAM) and bronchopulmonary sequestration (BPS).

Aim: To establish a CT-based classification system for hybrid lesions in children, elucidate misdiagnosis mechanisms, and propose optimized clinical management pathways through comparative analysis with isolated CPAM and BPS.

Materials And Methods: This retrospective study analyzed 393 children with surgically confirmed congenital lesions (87 hybrids, 218 CPAMs, 88 BPS) from two centers (2010-2022). Hybrid lesions were classified preoperatively: Type A: cystic lesion + systemic arterial supply; Type B: solid lesion + systemic arterial supply; Type C: solid lesion - systemic arterial supply. Comparative analysis of clinical and imaging features was performed.

Results: Type A(51 cases, 58.6%): Predominantly Type 2 CPAMs (cyst diameter <2.85 cm, AUC = 0.963) with intralobar BPS (88.2%). Prenatal detection rate: 70.6% (36/51); symptomatic rate: 37.3% (19/51). Type B (33 cases, 37.9%): Solid lesions with extralobar BPS (78.8%). Prenatal detection rate: 84.8% (28/33); symptomatic rate: 24.2% (8/33). Type C (3 cases, 3.4%): 100% misdiagnosis due to absent systemic arterial supply. Hybrid lesions demonstrated significantly higher prenatal detection rates than isolated CPAMs and BPS (75.9% vs. 51.4% vs. 56.8%, P<0.001) but lower symptomatic rates (31.0% vs. 62.4% vs. 48.9%, P<0.001). Radiologically, hybrid lesions predominantly involved the left lower lobe (66.7% vs. 28.0% in CPAMs, P<0.001).

Conclusions: CT demonstrated 54.1% diagnostic accuracy for hybrid lesions. The proposed A/B/C classification clarifies misdiagnosis mechanisms, with left lower lobe predominance (66.7%) and systemic arterial supply (95.4%) as hallmark features. Microcystic Type 2 CPAMs (<2.85 cm) and extralobar BPS anatomical isolation synergistically reduce complication risks, providing an imaging-guided framework for risk-stratified management.