Brain involvement in multicentric Epstein-Barr virus-associated smooth muscle tumours in a child after kidney transplantation.

Epstein-Barr virus (EBV)-associated smooth muscle tumours (SMT) have been reported in young patients with induced immunosuppression associated with organ transplantation, acquired immunodeficiency syndrome or congenital immunodeficiencies. EBV-associated SMT are frequently multicentric or multifocal and often occur in unusual locations. We are reporting a case of EBV-associated multicentric SMT that occurred after kidney transplantation in a 2-year-old boy with a history of oligomeganephrony. Headaches and left VIth cranial nerve paralysis led to the discovery of a brain tumour 3 years after transplantation. There were multiple pulmonary, hepatic and splenic nodules and enlarged mesenteric lymph nodes. Histological examination revealed multicentric SMT of uncertain malignant potential. Further investigations using in situ hybridisation demonstrated EBV early RNAs in the nucleus of most tumour cells. The immunosuppressive therapy was reduced, and the child was treated with chemotherapy, but died 2 months later, due to neurological complications.