Enteropathy associated T cell lymphoma with Reed-Sternberg-like cells of B cell phenotype and genotype associated with Epstein-Barr virus infection

Abstract

EBV-positive B cell proliferations have been recognized in the setting of some T cell lymphomas. These B cell proliferations often differ to varying degrees in morphology and immunophenotype with a great proportion being Epstein-Barr virus (EBV)-positive with Reed-Sternberg (RS)-like morphology. We describe a case of a 76-year-old Caucasian male who presented to the Emergency Department (ED) with weight loss, abdominal pain, and multiple episodes of vomiting and diarrhea. He underwent a laparotomy with an intraluminal mass seen in the cecum. Histology showed atypical intermediate- to large-sized cells involving the full thickness of the bowel wall with numerous mitotic figures and apoptotic bodies. The adjacent uninvolved mucosa demonstrated villous blunting, increased intraepithelial lymphocytes, crypt elongation, and lamina propria plasmacytosis, consistent with the celiac enteropathy. Rare large transformed cells morphologically consistent with Reed-Sternberg cells (RS cells) were also identified in the mesenteric lymph nodes. Immunophenotyping showed the intermediate- to large-sized cells to be of T cell origin with strongly CD3, CD45, and TIA-1 positive; moderately positive for CD5; and variably positive for CD2, CD25, CD57, perforin, and granzyme B, with an aberrant loss of CD7. The large cells were moderately positive for PAX-5, CD79a, CD20, CD30, and MUM1. They also were positive for EBV latent membrane protein (EBV-LMP) and Epstein-Barr virus-encoded small RNA (EBER). Based on morphology and immunoprofile, a diagnosis of enteropathy associated T cell lymphoma (EATL) with Reed-Sternberg-like cells associated with EBV virus infection was made. This is a rare phenomenon; the presence of large B cell proliferations in EATL, to our knowledge, is yet to be reported.