title: Clinical features and prognosis of gastric MALT lymphoma with special reference to responsiveness to H. pylori eradication and API2-MALT1 status.
abstract: OBJECTIVE
  Clinicopathologic characteristics and prognosis of Helicobacter pylori eradication-resistant gastric MALT lymphoma have not been well clarified. We analyzed a consecutive series of gastric MALT lymphomas at our institution regarding treatment, clinical course, and prognosis, with special reference to responsiveness to H. pylori eradication and presence of API2-MALT1.
  
  
  METHODS
  Subjects were 92 consecutive patients with gastric MALT lymphoma. Seventy were H. pylori positive, and 87 received H. pylori eradication therapy. The remaining five cases were API2-MALT1 positive and did not receive eradication treatment. Second-line treatments were radiation therapy, total gastrectomy, and chemotherapy (rituximab, rituximab plus CHOP, or rituximab plus 2-chlorodeoxyadenosine).
  
  
  RESULTS
  Gastric MALT lymphoma was classified into three groups, except one case with API2-MALT1 who responded to H. pylori eradication therapy: responders without API2-MALT1 (group A, N = 56, 65%), nonresponders without API2-MALT1 (group B, N = 16, 19%), and nonresponders with API2-MALT1 (group C, N = 14, 16%). Most cases in group A attained complete remission (CR) in 2 or 3 months and CR persisted for an average of 51.1 months (3-134 months). Recurrence was only seen in one case. In groups B and C, radiation therapy, chemotherapy, and total gastrectomy resulted in CR in 13, 5, and 2 cases, respectively. In 5 group B patients and 6 group C patients who did not undergo second-line therapy, disease did not progress for an average of 10.4 and 40.1 months, respectively. In 1 group C case who did not receive second-line treatment, lymphoma metastasized to the lung 12 yr after eradication. All group B patients and all but 2 group C patients remain alive; one of these deaths was from gastric carcinoma developing 7 yr after eradication.
  
  
  CONCLUSIONS
  Gastric MALT lymphoma responding to H. pylori eradication demonstrated good prognosis, and for nonresponsive cases, second-line treatments resulted in CR. However, careful observation for development of gastric carcinoma and disease progression is essential during follow-up of API2-MALT1-positive MALT lymphoma when patients decline second-line treatment.
authors: Department of Endoscopy, Aichi Cancer Center Hospital, Nagoya, Japan.
authors: Tsuneya
authors: T
authors: Nakamura
authors: Masao
authors: M
authors: Seto
authors: Masahiro
authors: M
authors: Tajika
authors: Hiroki
authors: H
authors: Kawai
authors: Takio
authors: T
authors: Yokoi
authors: Yasushi
authors: Y
authors: Yatabe
authors: Shigeo
authors: S
authors: Nakamura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000378:metabolism; D001706:Biopsy; D003131:Combined Modality Therapy / Q000379:methods; D004273:DNA, Neoplasm / Q000235:genetics; D016099:Endoscopy, Gastrointestinal; D005260:Female; D005500:Follow-Up Studies; D016481:Helicobacter Infections / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D016480:Helicobacter pylori / Q000187:drug effects / Q000302:isolation & purification*; D006801:Humans; D018442:Lymphoma, B-Cell, Marginal Zone / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D015514:Oncogene Proteins, Fusion / Q000235:genetics / Q000378:metabolism*; D011379:Prognosis; D054328:Proton Pump Inhibitors / Q000627:therapeutic use*; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000628:therapy
chemical_list: C415943:API2-MALT1 fusion protein, human; D000900:Anti-Bacterial Agents; D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D015514:Oncogene Proteins, Fusion; D054328:Proton Pump Inhibitors