Primary Low-Grade Myxofibrosarcoma Arising in a Nonfunctioning Renal Allograft 25 Years After Transplantation: A Rare Case Report.

BACKGROUND/AIM: Myxofibrosarcoma is an uncommon mesenchymal tumor which is categorized in the soft tissue sarcomas. Most commonly occurs in the subcutaneous tissue of the extremities. Our aim is to report a rare case of MFS arising from the non-functional renal graft which has never been reported in the past. CASE PRESENTATION: A 74-year-old man with past medical history of renal transplantation and lymphoma non-Hodgkin was admitted for elective renal transplanectomy after random radiological findings. The patient did not refer other symptoms and, after proper imaging with enhanced-contrast Computed Tomography and Magnetic Resonance Imaging, he was led to the operation room. RESULTS: The renal graft was excised successfully. The postoperative course of the patient was uneventful. The histological examination of the specimen demonstrated low grade Myxofibrosarcoma and clear margins were achieved. CONCLUSIONS: In spite of a wide range of therapeutic options for MFS described in the literature, the efficacy of those available therapies is not well established. Additionally, the high percentage of local recurrence resulting the clear-margins excision to be the gold standard therapy.