Multifocal Histologically Malignant Epstein–Barr Virus–Associated Smooth Muscle Tumor in a Pediatric Transplant Patient With an Indolent Course

Abstract

Epstein–Barr virus–associated smooth muscle tumors (EBV-SMTs) are rare lesions that occur in immunocompromised patients. Dural involvement appears to be less common in organ transplant recipients than in HIV patients. Due to the paucity of reported cases following organ transplantation, the natural history of these lesions is unclear. We describe an 8-year-old female who presented with adrenal, small bowel, and intracranial tumors 6 years following renal transplantation. Histopathological analysis revealed a highly cellular, mitotically active, smooth muscle neoplasm without necrosis. The tumor stained diffusely for smooth muscle actin and myosin. In situ hybridization for EBV-encoded RNA was diffusely positive. Following gross total resection, antiviral therapy, and a reduction in immunosuppression, the patient is tumor-free at 3 years follow-up. In patients with compromised immune systems, it is important to recognize this unique form of SMT because, even when there are multiple lesions, the prognosis may be excellent.