Although Epstein-Barr virus (EBV) infection has been known to be associated with a heterogeneous group of malignancies including Hodgkin lymphoma (HL), its association with smooth-muscle tumors (SMTs) has recently been described. Of these SMTs, a primary intracranial EBV-associated leiomyosarcoma (EBV-LMS) is extremely rare, and most of the reported cases were of immunocompromised and/or pediatric patients.
A neurologically asymptomatic, previously healthy 27-year-old man was found to have a PET-positive brain lesion during a staging workup for his recently diagnosed HL. Subsequent MRI revealed a 2.6 × 4.0 × 3.3–cm inhomogeneously enhancing tumor with marked surrounding edema in the right anterior frontal lobe. He was serologically HIV negative. He underwent a right frontal lobectomy with gross-total resection of the tumor. Intraoperatively, the tumor had fairly discrete margins and appeared to arise from the anterior falx (that is, it was dural based).
Microscopically, the tumor was composed of interlacing fascicles of spindle cells with brisk mitotic activity and multiple foci of necrosis. Immunohistochemically, the tumor cells were positive for caldesmon and smooth-muscle actin and negative for desmin, CD34, CD99, bcl-2, S100 protein, and GFAP. A Ki-67 labeling index was up to 30%. Epstein-Barr virus–encoded RNA in situ hybridization demonstrated strong diffuse positivity with more than 90% of tumor cells staining. Most of the Reed-Sternberg cells in HL were also labeled with Epstein-Barr virus–encoded RNA.
This is the first case of a concurrent occurrence of rare intracranial EBV-LMS and HL in a seemingly “immunocompetent” adult patient (immunocompetence determined by routine laboratory data and clinical history). We should be aware of EBV-SMT as a differential diagnosis of dural-based spindle cell neoplasm in this setting given that patients with HL, even at presentation, exhibit a persistent defect in cellular immunity.