mTOR inhibition with sirolimus is associated with a durable response in HIV associated multifocal Epstein-Barr Virus associated smooth muscle Tumour (EBV-SMT) and mini review of novel therapeutic options

Epstein-Barr Virus associated smooth muscle tumour (EBV-SMT) is a rare tumour with an estimated prevalence of <2 cases per million. It develops in patients who are immunocompromised and in whom the risk of EBV reactivation causing tumorigenesis is high. Examples of immunocompromised states include patients infected with human immunodeficiency virus (HIV), patients on iatrogenic immunosuppression following transplantation and patients with primary/congenital immunodeficiency. Although the association between EBV and development of EBV-SMT is well established, the underlying pathophysiology for this association is unclear. We present a case of a patient with HIV related EBV-SMT who has been on treatment with sirolimus for more than 5 years with disease continuing to remain controlled, clearly demonstrating the durable activity of sirolimus in the management of EBV-SMT. We scrutinized the literature pertaining to novel therapeutics which have been used for the management of EBV-SMTs and set it into context with other EBV associated neoplasms. To our knowledge, this is the first case report of a patient treated with sirolimus and we recommend that mTOR inhibition with sirolimus be considered as a first therapeutic option together with HAART in patients with HIV associated EBV-SMTs.