¹Second Department of Pathology, Okayama University Graduate School of Medicine and Denistry, Okayama, Japan

Correspondence: Tadaatsu Akagi, M.D., Ph.D., Department of Pathology, Okayama University Graduate School of Medicine and Dentistry, 2-5-1 Shikata-cho, Okayama, 700-8558, Japan. e-mail: akagi@cc.okayama-u.ac.jp; fax 81-86-235-7156.

Accepted 30 March 2001.

Abstract

Expression of adhesion molecule in low-grade B-cell mucosa-associated lymphoid tissue (MALT) lymphoma of the gastrointestinal tract has been reported in recent years, but these reports have primarily focused on low-grade gastrointestinal MALT lymphoma. In this study, we examined the lymphocytic homing receptor 47 integrin, L-selectin, and VLA-4 and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in low-grade lymphoma of the gastrointestinal tract and other organs such as the ocular adnexa and thyroid. We also observed changes in the expression pattern associated with high-grade transformation. Neoplastic cells in the gastrointestinal low-grade lymphoma and the low-grade component of high-grade MALT lymphoma were found to be 47 integrin⁺, L-selectin⁺, whereas the gastrointestinal high-grade component and diffuse large B-cell lymphoma were found to be 47 integrin^-, L-selectin^-. High endothelial venules in the gastric MALT lymphomas expressed MAdCAM-1. In the ocular adnexa low-grade MALT lymphoma, most cases were 47 integrin^-, L-selectin⁺; and in the thyroid, most cases of both low- and high-grade MALT lymphoma were 47 integrin^-, L-selectin^-. These findings show that 47 integrin and L-selectin may play an important role in the lymphocyte homing of gastrointestinal low-grade MALT lymphoma and in the loss of 47 integrin expression throughout the course of high-grade progression.