CASE DESCRIPTION
A 41-year-old HIV-positive male presented to the emergency department with fever, malaise, and shortness of breath. Splenomegaly was noted on physical exam but no lymphadenopathy or cavitary effusions. His viral load was markedly elevated with CD4 count of 16 cells/µL, and he was pancytopenic. Clinical suspicion was high for infection, acute leukemia, or hemophagocytic lymphohistiocytosis. Bone marrow biopsy showed sheets of large atypical mononuclear cells with open chromatin, distinct nucleoli, and ample basophilic cytoplasm (Figures 1A & B). Tumor cells were positive for CD138 (Figure 1C) and CD30 (Figure 1D) while negative for CD45, CD3, CD20, PAX5, OCT2, and CD79a. Differential diagnoses included plasmablastic lymphoma, plasma cell myeloma with plasmablastic features, and primary effusion lymphoma (PEL). Both EBV by in situ hybridization (Figure 1E) and HHV-8 (Figure 1F) were positive in tumor cells; hence, the diagnosis of extracavitary PEL was rendered. Chemotherapy with EPOCH was initiated; nevertheless, the patient died of disease 19 days after diagnosis.
PEL is a distinct clinicopathologic entity of AIDS-related lymphomas. Extracavitary PEL is a rare clinical variant of PEL that presents with solid tumor lesions in absence of malignant serous effusions.1,2 This case highlights the importance of recognizing PEL outside of cavitary lesions.