Case of Primary Central Nervous System Lymphoma Arising at Site of Remote Herpes Encephalitis

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is a rare malignancy that usually arises in the context of severe immunosuppression but has incompletely understood etiology, limiting effective treatments. CASE DESCRIPTION: We present the case of an 81-year-old immunocompetent man who developed a PCNSL in the right temporal lobe, at the site of a remote episode of herpes simplex virus (HSV) encephalitis 8 years prior. There are numerous viruses with known oncogenic associations; however, to our knowledge, this is the first reported case of PCNSL with an antecedent HSV infection. CONCLUSIONS: We discuss this case in the context of our current understandings of the pathogenesis of HSV encephalitis and PCNSL and postulate mechanisms through which the 2 could be associated.