title: Bone marrow involvement is rare in superficial gastric mucosa-associated lymphoid tissue lymphoma.
abstract: BACKGROUND
  The initial staging work-up of gastric mucosa-associated lymphoid tissue (MALT) lymphoma includes bone marrow examination. Since gastric MALT lymphoma is mostly detected in early stages with the national cancer screening programme in Korea, bone marrow is rarely involved.
  
  
  OBJECTIVE
  To investigate the incidence of bone marrow involvement in gastric MALT lymphomas and the role of bone marrow examination for an initial staging work-up.
  
  
  METHODS
  Patients diagnosed with gastric MALT lymphoma at Seoul National University Hospital from January 2005 to July 2014 were enrolled. Clinical databases of the patients were retrospectively reviewed.
  
  
  RESULTS
  Out of 105 patients, 91 (86.7%) were classified as stage IE1. Among these patients, 78 patients with Helicobacter pylori infection underwent eradication therapy, and complete remission was achieved in 74 cases (94.9%). Twelve out of 13 patients (92.3%) without H. pylori infection underwent radiotherapy or surgery and all achieved complete remission. Bone marrow involvement was proven in only one patient (1.0%).
  
  
  CONCLUSIONS
  Bone marrow involvement was rare in patients with only superficial gastric MALT lymphoma without extragastric invasion. Further studies are warranted to identify the risk factors of bone marrow involvement in gastric MALT lymphoma.
authors.affiliation: Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jae Yong
authors.initials: JY
authors.lastname: Park
authors.affiliation: Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea. Electronic address: harley@snu.ac.kr.
authors.forename: Sang Gyun
authors.initials: SG
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Joo Sung
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Hyun Chae
authors.initials: HC
authors.lastname: Jung
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D044963:Biopsy, Fine-Needle; D001853:Bone Marrow / Q000473:pathology*; D019046:Bone Marrow Neoplasms / Q000473:pathology* / Q000556:secondary; D002648:Child; D019160:Endosonography; D005260:Female; D005500:Follow-Up Studies; D016481:Helicobacter Infections / Q000150:complications / Q000188:drug therapy*; D016480:Helicobacter pylori; D006801:Humans; D018442:Lymphoma, B-Cell, Marginal Zone / Q000150:complications / Q000473:pathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000628:therapy*; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D054328:Proton Pump Inhibitors / Q000627:therapeutic use; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000150:complications / Q000473:pathology* / Q000628:therapy; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D054328:Proton Pump Inhibitors
keywords: Bone marrow; MALT lymphoma; Staging