[Lung transplantation and post-transplantation changes in patients with pneumoconiosis: a clinicopathological analysis of 28 cases]

Objective: To investigate the clinicopathological characteristics of lung transplantation and post-transplantation changes in patients with pneumoconiosis. Methods: A retrospective study was conducted to analyze the clinical and pathological data of 28 patients with pulmonary silicosis who underwent lung transplantation and were managed at the Department of Internal Medicine, Henan Provincial People's Hospital, Zhengzhou, China from January 2015 to December 2024. Among them, 8 patients underwent lung biopsy 6-20 months after transplantation to evaluate the histopathological changes of the recipient and the donor lungs post-transplantation. The expression of relevant indicators was examined using immunohistochemical EnVision staining, while presence of microorganisms was assessed using histochemical special staining. The patients were all followed up. Results: Among the 28 patients with pneumoconiosis who underwent lung transplantation, 26 were male and 2 were female, with a male-to-female ratio of 13∶1. Their ages ranged from 23 to 68 years, median 50.0 (46.0, 53.5) years. They were diagnosed with pneumoconiosis at local occupational disease prevention and control centers for 3 to 15 years (mean, 9.65 years), including 13 left single lung transplants and 15 right single lung transplants. Gross examination showed fleshy nodules with irregular cystic cavities at the periphery. The cut surfaces exhibited gray-brown color and firm texture. Microscopically, most alveolar structures of the lung were obliterated, with nodular or diffuse proliferation of collagen fibers accompanied by hyaline degeneration. Focal massive carbon dust deposition and massive silicotic fibrosis were observed, surrounded by lung parenchyma with emphysematous changes and localized bullae formation. Seven patients underwent re-biopsy after transplantation that showed extensive infiltration of inflammatory cells. In 4 cases, microscopy revealed complete coagulative necrosis, with negative acid-fast staining and TB-DNA results. Of the 4 cases, 3 cases exhibited Aspergillus infection confirmed by Grocott's methenamine silver and PAS stains, while 2 cases showed chronic bronchitis with squamous metaplasia. Follow-up revealed that 8 patients died of acute respiratory failure due to severe infection, while the remaining 20 demonstrated significant postoperative improvement in lung function. Conclusions: For patients with advanced pulmonary dust deposition disease who undergo lung transplantation, it is necessary to conduct standardized sampling and pathological assessment of the recipient lungs. In the early post-transplant period, the complications of re-biopsy tissues are mainly fungal infections. The combination of morphological manifestations and immunohistochemical detection is helpful to distinguish infection from rejection reactions. At the same time, it is essential to integrate clinical information and laboratory results to provide post-transplantation pathological assessment for individualized treatment.