Colonal monomorphic epitheliotropic intestinal T-cell lymphoma with novel phenotype of cytoplasmic CD3 expression.

Colonal monomorphic epitheliotropic intestinal T-cell lymphoma with novel phenotype of cytoplasmic CD3 expression. J Clin Exp Hematop. 2018 Apr 13;: Authors: Aoyama Y, Tsunemine H, Zushi Y, Maruoka H, Goto Y, Kodaka T, Itoh T, Takahashi T Abstract Monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) is a new clinical entity that was reclassified from enteropathy-associated T-cell lymphoma in the 2016 WHO classification. An 83-year-old man with fever and diarrhea was referred to our hospital because of free air in the abdominal cavity and wall thickening of the large intestine on CT. Colonofiberscopic examination revealed mucosal edema and multiple ulcers at the sigmoid colon, splenic flexure, and transverse colon. Histopathological examination of the mucosal biopsy specimen demonstrated dense infiltration of small lymphocytes with nuclear atypia, some of which exhibited intraepithelial invasion. Immunohistologically, these lymphocytes were positive for CD3, CD56, and perforin. Regarding CD3 expression, the antigen was found to only be expressed in the cytoplasm and not on the surface membrane on flow cytometric analysis. PCR examination of the T-cell receptor (TCR) gene revealed monoclonal gene rearrangements of TCR-γ and TCR-β. Based on these findings, a diagnosis of colonal MEITL with cyCD3 expression at Lugano clinical stage 1 was made. After conservative management of the peritonitis, we treated the patient with CHOP ...
Source: Journal of Clinical and Experimental Hematopathology : JCEH - Category: Hematology Tags: J Clin Exp Hematop Source Type: research