title: Chromosome 17p allelic loss in colorectal carcinoma. Clinical significance.
abstract: OBJECTIVE
  To correlate allelic losses on chromosomes 5q, 8p, 17p, and 18q in colorectal adenocarcinomas with histopathologic features of known prognostic significance.
  
  
  METHODS
  DNA was extracted from paired samples of 56 fresh-frozen colorectal adenocarcinomas (one classified as Dukes' stage A, 22 as Dukes' stage B, 27 as Dukes' stage C, and six as Dukes'stage D) and adjacent normal mucosa.
  
  
  METHODS
  Specimens were resected at the University of Chicago (Ill) and the University of Padova (Italy) in 1991.
  
  
  METHODS
  Samples were obtained from consecutive patients.
  
  
  METHODS
  Chromosomes 5q, 8p, 17p, and 18q were studied for loss of heterozygosity by means of Southern hybridization blot analysis of restriction fragment length polymorphisms, and the results were correlated with pathologic tumor stage, degree of differentiation, and lymphatic and/or vascular microinvasion.
  
  
  RESULTS
  Chromosomes 17p and 18q exhibited the highest frequency of loss of heterozygosity (40.6% and 48.8%, respectively). Most of the allelic losses were found in advanced tumors (60% in Dukes' stages C and D combined). A statistically significant correlation was found between loss of heterozygosity on chromosome 17p and the presence of lymphatic and/or vascular microinvasion (P < .01, Fisher's Exact Test).
  
  
  CONCLUSIONS
  There was a significant correlation between loss of heterozygosity on chromosome 17p and the presence of lymphatic and/or vascular microinvasion in colorectal adenocarcinoma, a known stage-independent negative prognostic risk factor. Detection of loss of heterozygosity on chromosome 17p may identify a group of patients who may benefit from more aggressive surgical and/or early adjuvant therapy.
authors.affiliation: Department of Surgery, University of Chicago, Ill., USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Takanishi
authors.forename: I
authors.initials: I
authors.lastname: Angriman
authors.forename: M L
authors.initials: ML
authors.lastname: Yaremko
authors.forename: A
authors.initials: A
authors.lastname: Montag
authors.forename: C A
authors.initials: CA
authors.lastname: Westbrook
authors.forename: F
authors.initials: F
authors.lastname: Michelassi
mesh_terms: D000483:Alleles; D002872:Chromosome Deletion; D015179:Colorectal Neoplasms / Q000235:genetics*; D004273:DNA, Neoplasm / Q000235:genetics; D006801:Humans
chemical_list: D004273:DNA, Neoplasm