MEITL : Intro & Clinical
Introduction: Monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) is a primary intestinal T-cell lymphoma not associated with celiac disease. It was previously known as enteropathy-associated T-cell lymphoma (EATL), type II. However, due to distinctive clinical, morphologic, and immunophenotypic features, it was recognized as a separate entity by the WHO in 2016. Unlike EATL, MEITL is less common in Northern Europeans but is more prevalent in Asian and Hispanic individuals. It arises from intraepithelial lymphocytes. The neoplastic cells are monomorphic with medium-sized round nuclei and scant pale cytoplasm. Unlike EATL, it lacks an inflammatory component and necrosis is less prominent. Clinical Features: The clinical presentation includes abdominal pain, symptoms/signs of intestinal obstruction or perforation, weight loss, and gastrointestinal bleeding. There is usually no history of malabsorption. The most commonly involved site is small intestine (jejunum > ileum). It forms a tumor mass with or without ulceration. The neoplastic cells frequently spread laterally into the adjacent mucosa. Mesenteric lymph nodes are commonly involved. In advanced cases, extranodal sites may be affected. This low magnification view shows an area of mucosal ulceration (location : jejunum) in MEITL.