title: Primary gastrointestinal T-cell lymphoma resembling multiple lymphomatous polyposis.
abstract: An extremely rare case of primary gastrointestinal T-cell lymphoma involving the stomach and intestine is reported. Radiographic and endoscopic examinations showed multiple polypoid lesions covered by a normal-appearing mucosa in the stomach, duodenal bulb, and terminal ileum and numerous small aphthoid lesions throughout the entire colorectum. Histopathologic, immunohistochemical, and polymerase chain reaction studies were performed using paraffin-embedded or fresh-frozen specimens from endoscopic biopsies and endoscopic mucosal resections. All lesions were composed of small, atypical lymphoid cells, which were classified as low-grade pleomorphic lymphoma. The tumor cells expressed CD3, CD4, and the T-cell receptor gamma gene phenotype as well as human mucosal lymphocyte 1 antigen, suggesting that the lymphoma cells were derived from intraepithelial T lymphocytes. This is the first description of primary gastrointestinal T-cell lymphoma with expression of human mucosal lymphocyte 1 antigen and a novel morphology resembling multiple lymphomatous polyposis.
authors.affiliation: Division of Gastroenterology, Matsuyama Red Cross Hospital, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Hirakawa
authors.forename: T
authors.initials: T
authors.lastname: Fuchigami
authors.forename: S
authors.initials: S
authors.lastname: Nakamura
authors.forename: Y
authors.initials: Y
authors.lastname: Daimaru
authors.forename: K
authors.initials: K
authors.lastname: Ohshima
authors.forename: Y
authors.initials: Y
authors.lastname: Sakai
authors.forename: T
authors.initials: T
authors.lastname: Ichimaru
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D003106:Colon / Q000000981:diagnostic imaging / Q000473:pathology; D005770:Gastrointestinal Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008223:Lymphoma / Q000473:pathology*; D016399:Lymphoma, T-Cell / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011127:Polyps / Q000473:pathology*; D011859:Radiography; D013270:Stomach / Q000473:pathology