tacrolimus and Smooth-Muscle-Tumor

A 27-year old caucasian male was diagnosed 2.7 years after kidney transplantation with Epstein-Barr virus (EBV)-associated smooth muscle tumors in liver and spleen. The reduction in immunosuppression and conversion from tacrolimus to sirolimus did not lead to a regression of the tumors. Additionally, the patient developed a cellular rejection of his renal allograft, which was successfully treated. A combined approach with stereotactic radiofrequency ablation (SRFA) and surgical resection was effective in the treatment of the tumors.

Topics: Adult; Epstein-Barr Virus Infections; Graft Rejection; Herpesvirus 4, Human; Humans; Immunocompromised Host; Immunosuppressive Agents; Kidney Transplantation; Liver; Male; Radiosurgery; Sirolimus; Smooth Muscle Tumor; Spleen; Tacrolimus; Treatment Outcome

Smooth-muscle tumors, benign and malignant, are increasingly recognized in children who are immunocompromised because of HIV infection and organ transplantation. We report a case of an EBV-associated smooth-muscle tumor, of unusual location arising in a seven-year-old post-transplant patient who was previously treated for a lymphoproliferative disease. Five years after liver transplantation, a mesenteric tumor was diagnosed. The tumor was composed of spindle cells with smooth-muscle features. Immunohistochemical analysis was positive for muscle-specific actin and desmin, negative for EBV latent membrane protein (LMP-1). In situ hybridization revealed nuclear EBV sequences. This case underlines the role of EBV infection in the development of unusual smooth-muscle tumors after organ transplantation. The evolution of these rare tumors is uncertain.

Topics: Child; Herpesvirus 4, Human; Humans; Immunosuppressive Agents; Liver Transplantation; Male; Mesentery; Peritoneal Neoplasms; Smooth Muscle Tumor; Tacrolimus