[Pulmonary Kaposi sarcoma after lung transplantation: a case report and literature review]

Objective: To investigate the clinical features, diagnosis, and treatment of pulmonary Kaposi sarcoma (KS) after lung transplantation. Methods: A case of pulmonary KS after bilateral lung transplantation was retrospectively analyzed. Two key words "Kaposi sarcoma" and "lung transplant*" were used to search for relevant literature in SinoMed, Wanfang Data, CNKI, PubMed, Embase, Cochrane Library and Web of Science, with a cut-off date of July 31^st, 2024. Results: Five months after bilateral lung transplantation, the patient developed multiple solid nodules in both transplanted lungs, which were diagnosed as KS by histopathological examination. After reduction of immunosuppression and the prescription of sirolimus, the lung lesions regressed. A total of 40 English articles were identified; after screening, 25 patients with KS following lung transplantation were included in the study. Including this case, 26 patients were included, comprising 19 males and 7 females, with a mean age of 15~68(52.3±13.7) years. Of these, 18 underwent bilateral lung transplantation, 3 had single lung transplantation, and the transplant types for 5 patients were unknown. The median interval between KS diagnosis and transplantation was 8.0 months (IQR 6.0-18.0). There were 11 cases of disseminated KS, 7 cases of pulmonary KS, 4 cases of skin KS, 2 cases of gastric KS, 1 case of small intestinal KS, and 1 case of lymph node KS. Of the patients, 10 responded to treatment, 15 died, and the outcome of 1 patient outcome was unknown. Conclusions: The clinical manifestations of KS after lung transplantation are non-specific and diagnosis is based on histopathology. Reducing immunosuppression in conjunction with rapamycin-targeted protein inhibitors may be an effective treatment strategy.