title: Histological grading in gastric lymphoma: pretreatment criteria and clinical relevance.
abstract: OBJECTIVE
  Stomach-conserving therapy in primary gastric non-Hodgkin's lymphoma (mucosa-associated lymphoid tissue [MALT]-NHL) is increasingly gaining importance as an alternative to surgery. As a consequence, surgical pathologists have to define histological criteria in pretreatment endoscopic biopsy specimen samples not only to make the diagnosis but also to recognize minor tumor components that may infer a significantly adverse impact on prognosis. The aim of this study was to define histological criteria for clinically significant tumor progression in pretreatment endoscopic biopsy specimens.
  
  
  METHODS
  In a consecutive series of 106 patients with gastric MALT-NHL, the prognostic impact of large cell components was assessed by semiquantitative analysis of clusters and diffusely intermingled malignant blasts.
  
  
  RESULTS
  In low-grade MALT-NHL, a category with a diffuse large cell component of 1%-10% with or without nonconfluent clusters of blasts could be separated with a significantly worse prognosis (10-year disease-specific survival, 90% vs. 75%). No clinical parameters of known prognostic significance could account for this difference.
  
  
  CONCLUSIONS
  It is possible to define criteria in endoscopic biopsy specimens to recognize clinically relevant tumor progression. To serve as a guideline in the choice of treatment, these criteria should be validated prospectively in future clinical trials.
authors.affiliation: Department of Pathology, The Netherlands Cancer Institute, Amsterdam.
authors.forename: D
authors.initials: D
authors.lastname: de Jong
authors.forename: H
authors.initials: H
authors.lastname: Boot
authors.forename: P
authors.initials: P
authors.lastname: van Heerde
authors.forename: G A
authors.initials: GA
authors.lastname: Hart
authors.forename: B G
authors.initials: BG
authors.lastname: Taal
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D005260:Female; D005753:Gastric Mucosa / Q000473:pathology; D006801:Humans; D008221:Lymphoid Tissue / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000473:pathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D013274:Stomach Neoplasms / Q000473:pathology* / Q000628:therapy; D016019:Survival Analysis; D016896:Treatment Outcome