title: Helicobacter pylori-negative gastric mucosa-associated lymphoid tissue lymphoma: a clinicopathologic and molecular study with reference to antibiotic treatment.
abstract: BACKGROUND
  The majority of gastric mucosa-associated lymphoid tissue (MALT) lymphoma develops in Helicobacter pylori-associated chronic gastritis. Little is still known regarding the clinicopathologic features of gastric MALT lymphoma not associated with H. pylori infection.
  
  
  METHODS
  One hundred thirty-seven patients with gastric MALT lymphoma, in whom H. pylori status was evaluated using at least both serology and histology, were enrolled. Clinical, histopathologic, and molecular findings were compared between H. pylori-negative group (n = 12; 9%) and H. pylori-positive group (n = 125; 91%). t(11;18)(q21;q21) was investigated by reverse-transcription polymerase chain reaction and interphase fluorescence in situ hybridization.
  
  
  RESULTS
  In cases without diffuse large B-cell lymphoma (DLBCL) component, H. pylori-negative lymphomas located more frequently in the proximal stomach (70%), less frequently appeared as superficial type (40%), and frequently invaded the submucosa or beyond (70%). Histologically, lymphoepithelial lesions (57%), lymphoid follicles (43%), and background mucosal atrophy (50%) in the H. pylori-negative group were less frequent than in the H. pylori-positive group (91%, 93%, and 100%, respectively). The frequencies of t(11;18)(q21;q21) (100%) and BCL10 nuclear expression (100%) in the H. pylori-negative group were significantly higher than in the H. pylori-positive group (2% and 27%, respectively). Response to antibiotic treatment was observed not only in the H. pylori-positive group (75%), but also in the H. pylori-negative group (2 of 7 patients, 29%). In cases with a DLBCL component, such differences were not observed between the 2 groups.
  
  
  CONCLUSIONS
  H. pylori-negative gastric MALT lymphoma is characterized by frequent t(11;18)(q21;q21). Antibiotic treatment should be considered also for this disease, although cases with t(11;18)(q21;q21) may need additional strategies.
authors.affiliation: Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. sn330@cam.ac.uk
authors.forename: Shotaro
authors.initials: S
authors.lastname: Nakamura
authors.forename: Takayuki
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Hongtao
authors.initials: H
authors.lastname: Ye
authors.forename: Shigeo
authors.initials: S
authors.lastname: Nakamura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Suekane
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Matsumoto
authors.forename: Takashi
authors.initials: T
authors.lastname: Yao
authors.forename: Masazumi
authors.initials: M
authors.lastname: Tsuneyoshi
authors.forename: Ming-Qing
authors.initials: MQ
authors.lastname: Du
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Iida
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D005260:Female; D016480:Helicobacter pylori / Q000302:isolation & purification; D006801:Humans; D018442:Lymphoma, B-Cell, Marginal Zone / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents