Aberrant CD3 positive plasmablastic lymphoma of small bowel in a HIV negative, EBV negative patient: A case report

Plasmablastic lymphoma (PBL) is an aggressive lymphoma with the proliferation of plasmablastic cells with a plasma cell immunophenotype and immunonegativity for B-cell markers. Here we present a case of jejunal PBL in an 82-year-old human immunodeficiency virus (HIV) negative and Epstein-Barr (EBV) negative male who presented with subacute intestinal obstruction and histopathological examination showed a large cell lymphoma with plasmablastic differentiation diffusely infiltrating full thickness of the jejunal wall. Neoplastic cells were immunopositive for CD138, MUM-1, EMA, and CD56, along with aberrant expression of pan T-cell marker CD3. No restrictions for kappa and lambda light chains were noted. Ki67 index was >90%. Tumor cells were immunonegative for CD20, CD5, CD7, CD30, and PAX 5. Suspicion of this rare and high-grade lymphoma in immunocompetent patients and at extra-nodal locations along with awareness of diagnostic pitfalls in its immunoprofile will aid in accurate diagnosis and prognostication.