Primary Gastric T-Cell Lymphoma Not Associated with Human T-Lymphotropic Virus Type 1

Introduction

Most primary gastric lymphomas are of B-cell origin, whereas a gastric T-cell lymphoma is extremely rare.1 The majority of primary gastric T-cell lymphoma cases are secondary to adult T-cell leukemia/lymphoma (ATL).2 Human T-lymphotropic virus type 1 (HTLV-1) is a retrovirus and is prevalent in south- ern Japan, the Caribbean Basin, and Africa. HTLV-1 infection is widely accepted as a cause of ATL.3 The clinicopatho- logical features of primary gastric T-cell lymphoma remain to be clarified. Here, we report a case of primary gastric T-cell lymphoma not associated with HTLV-1, and compare the find- ings from our case with those from other cases reported in Japan.

Abstract

Most primary gastric lymphomas are of B-cell origin, whereas a gastric T-cell lymphoma is extremely rare. We report a 73-year-old Japanese man with primary gastric T-cell lymphoma not associated with human T-lymphotropic virus type 1 (HTLV-1). In March 2009, the patient was admitted to our hospital with the chief complaint of weight loss of 6 kg over 6 months. HTLV-1 was negative by the particle agglutination (PA) method. An upper gastrointestinal endoscopy revealed a large ulcerated tumor with a partially cleaved bank at the greater curvature of the cardia. A computed tomography scanning demonstrated thickening of the gastric wall and tumor invasion into the liver and spleen; no apparent lymph node swelling was noted in the chest or abdomen. Total gastrectomy with splenectomy and partial resection of the diaphragm and liver were performed in May 2009. Hematoxylin and eosin staining of the surgical specimens showed diffuse infiltration with medium atypical lymphocytes. Immunohistochemically, the cells were positive for CD3, CD8, CD45RO, and CD30, but negative for CD4 and CD79α. Based on these histological findings, the tumor was diagnosed as a diffuse, medium type according to the Lymphoma Study Group classification and peripheral T-cell lymphoma, unspecified as per the WHO histological classification. Currently, at 17 months since diagnosis, the patient is still alive.

Keywords

T-cell lymphoma, gastric lymphoma, HTLV-1