Pathologists' experience and routine practice in high-volume lung transplant centers: An international survey

Lung allograft pathology encompasses a wide spectrum of disorders, with new entities and emerging diagnostic technologies. The main goal of this study was to document pathologists' current global practices and highlight areas of consensus and divergence worldwide. A 24-item survey was distributed to transplant centers and responses were received from 35 specialists (51% European, 49% non-European). Most centers used both surveillance and symptom-driven assessments (77%), mainly with transbronchial biopsies (86%) and bronchoalveolar lavage (83%). Non-European centers were more likely to adopt digital pathology (OR 3.03), to use donor-derived cell-free DNA (dd-cfDNA) (OR 2.94), and supported large airway sampling (OR 2.27). Larger centers used dd-cfDNA (OR 2.75) more frequently and consider large airway sampling (OR 2.18). Responders largely supported standardized reporting (86%), reintroducing grade AX (94%), and independent bronchial lesion scoring (82%). Most endorsed an "indeterminate" category for acute and chronic rejection. These findings reflect evolving practices in the field and will inform the ongoing revision of the Lung Allograft Pathology Working Classification.