Fulminant intracranial Epstein–Barr virus-associated smooth muscle tumour from acquired immunodeficiency syndrome: durable control induced by immune reconstitution

Epstein–Barr virus-associated smooth muscle tumours (EBV-SMTs) are rare neoplasms primarily associated with acquired immunodeficiency syndrome (AIDS). Currently, its rarity limits development of standardized treatment guidelines. However, immune reconstitution through use of antiretroviral therapy (ART) plays a pivotal role. We describe a 46-year-old patient with AIDS and histology-proven intracranial EBV-SMT. The patient subsequently developed anal squamous-cell carcinoma (SCC). Craniotomy and primary tumour resection, followed by immune reconstitution without the use of systemic cancer therapy, resulted in long-term indolence and functional recovery. He underwent curative chemoradiation for his anal SCC and remains in remission for both malignancies. Although each malignancy is independently recognized in patients living with human immunodeficiency virus (PLHIV), we present a unique case of metachronous occurrence of EBV-SMT and anal SCC. This case highlights the therapeutic potential of ART-driven immune reconstitution in EBV-SMT and emphasizes the lifelong cancer risk in PLHIV even with successful immune recovery.