A case of primary gastric Burkitt-like lymphoma in the early stage diagnosed by endoscopic mucosal resection

Abstract

Dear Editor: Burkitt-like lymphoma (BLL) is a rare and rapidly progressive type of lymphoma that usually occurs in young males. In the Revised European– American Lymphoma (REAL) classification, BLLs are described as diffuse B-cell lymphomas with a high proliferative rate and molecular biological characteristics considered to be borderline between those of classic Burkitt lymphoma (BL) and those of diffuse large B-cell lymphoma (DLBCL). Although the gastrointestinal tract is one of the most common regions for extranodal malignant lymphomas, primary gastrointestinal lymphomas are rare. BL and BLL occur in various gastrointestinal sites, and 30–80% of patients have involvement of the small bowel or colon and rectum, especially the ileocecal region. Involvement of the stomach occurs in only 10% of the patients, and almost all of the cases were detected in the late stage as a bulky mass located in the abdomen or other gastrointestinal sites. Here we report a case of primary gastric BLL in the early stage. To the best of our knowledge, this is the first report of a case of BLL presenting with a submucosal tumor (SMT) that was diagnosed by endoscopic mucosal resection (EMR). In June 2003, a 52-year-old Japanese man underwent upper gastrointestinal endoscopy and a SMT measuring 20 mm was detected in the gastric antrum. Endoscopic pictures with indigocarmine spraying dye clearly revealed the surface of the SMT. It was extensible, nodular, and glossy with telangiectasia, and no ulcer was seen on the surface. The tumor was elastic and immovable, and four biopsy specimens showed inflammatory cell (neutrophil and plasma cell) invasion with infection by Helicobacter pylori. Endoscopic ultrasonography (EUS) (20 MHz) was performed to examine the inner parts of the SMT. The tumor was found to be a homogeneous hypoechoic lesion and to be located in the submucosal layer. A computed tomography (CT) scan showed neither bulky mass nor lymph node metastasis. On scintigraphy, there was no accumulation of gallium except in the stomach. No abnormality was detected in other portions of the alimentary tract by small-bowel examination and colonoscopy. Since the proper muscular layer of the tumor was thought to be intact, we thought that this tumor was resectable, and EMR was performed for diagnosis. Pathologically, the cut end of the resected specimen was negative. The tumor cells showed a very high mitotic rate and a nuclear variability in the submucosal layer. A starry-sky appearance and mediumsized lymphoid cells showing a jigsaw puzzle effect of cytoplasmic borders were seen in the tumor tissues. Immunohistochemically, tumor cells were positive for L-26 and K. Nosho (*) . M. Shitani . F. Takahashi . Y. Ikeda . A. Goto . H. Yamamoto . Y. Arimura . T. Ishida . T. Endo . K. Imai First Department of Internal Medicine, Sapporo Medical University, S.-1, W.-16, Chuo-ku, Sapporo, 060-8543, Japan e-mail: nosho@sapmed.ac.jp Tel.: +81-11-6112111 Fax: +81-11-6112282