title: Laser capture microdissection analysis reveals frequent allelic losses in papillary urothelial neoplasm of low malignant potential of the urinary bladder.
abstract: BACKGROUND
  In the 1999 World Health Organization classification system, papillary tumors of the urinary bladder were classified as papilloma, papillary urothelial neoplasm of low malignant potential (PUNLMP), and as Grade 1, Grade 2, and Grade 3 urothelial carcinoma. The biologic potential of PUNLMP of the urinary bladder is controversial. To the authors' knowledge, information regarding the genetic changes of PUNLMP tumors of the bladder is limited.
  
  
  METHODS
  The authors examined loss of heterogygosity (LOH) at 5 polymorphic microsatellite markers on chromosome 9q32-33 (D9S177), 9p22 (IFNA), 17p13.1 (TP53), 12q14-24 (D12S1051), and 3p25-26 (D3S3050) from 26 patients who were diagnosed with PUNLMP tumors of the urinary bladder. Tumors were microdissected from sections prepared from formalin-fixed, paraffin-processed tissue specimens using laser capture microdissection.
  
  
  RESULTS
  LOH was found in 21 of 26 (81%) patients with PUNLMP. The rate of LOH was 41% with D9S177, 32% with IFNA, 29% with TP53, 26% with D12S1051, and 44% with D3S3050. Allelic loss of multiple chromosome loci was often present in patients with PUNLMP tumors.
  
  
  CONCLUSIONS
  Genetic changes that commonly occur in advanced bladder carcinoma (> or = pT2) are frequently found in PUNLMP of the urinary bladder.
authors.affiliation: Department of Pathology and Laboratory Medicine, School of Medicine, Indiana University Medical Center, University Hospital 3465, 550 North University Boulevard, Indianapolis, IN 46202, USA. lcheng@iupui.edu
authors.forename: Liang
authors.initials: L
authors.lastname: Cheng
authors.forename: Gregory T
authors.initials: GT
authors.lastname: MacLennan
authors.forename: Shaobo
authors.initials: S
authors.lastname: Zhang
authors.forename: Mingsheng
authors.initials: M
authors.lastname: Wang
authors.forename: Chong-Xian
authors.initials: CX
authors.lastname: Pan
authors.forename: Michael O
authors.initials: MO
authors.lastname: Koch
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002295:Carcinoma, Transitional Cell / Q000235:genetics* / Q000473:pathology; D005260:Female; D006801:Humans; D007834:Lasers; D019656:Loss of Heterozygosity; D008297:Male; D042282:Microdissection; D018895:Microsatellite Repeats; D008875:Middle Aged; D010212:Papilloma / Q000235:genetics* / Q000473:pathology; D016133:Polymerase Chain Reaction; D001749:Urinary Bladder Neoplasms / Q000235:genetics* / Q000473:pathology; D019459:Urothelium / Q000473:pathology*