title: Value of the identification of microsatellite instability in colorectal cancer.
abstract: OBJECTIVE
  Recent studies defend a possible prognostic and therapeutic value of the identification of microsatellite instability (MSI) in colorectal cancer. This work tries to assess the impact that the identification of MSI tumours can have in clinical practice.
  
  
  METHODS
  We recovered tumour samples from 92 of the 143 patients operated on for colorectal cancer in our institution between 1995 and 2000. Five MSI markers (BAT 25, BAT 26, D2S123, D5S346 and D17S250) were studied on them. The rate and clinicopathologic characteristics of MSI tumours were investigated along with their impact on the global and disease-free survival as compared with microsatellite stable (MSS) tumours.
  
  
  RESULTS
  All 5 microsatellite markers' status were established in 73 patients (79.3% of the samples). Among them, 7 tumours showed instability in just one marker (low microsatellite instability [MSI-L]) whereas 5 tumours had mutations in 2 or more markers (high microsatellite instability [MSI-H]), for a total 15.4% rate of MSI tumours. All MSI-H tumours were located in the right colon. We could not fi nd any impact from MSI detection on global or disease-free survival.
  
  
  CONCLUSIONS
  MSI determination did not identify groups of patients with a different prognosis. Moreover, with such low incidence its determination can only be justified in those cases that fulfill Bethesda's criteria to identify families with Lynch's syndrome.
authors: General Surgery Department, Fundación Instituto Valenciano de Oncología, Valencia, Spain. antoniobarrasa@aecirujanos.es
authors: Antonio
authors: A
authors: Barrasa Shaw
authors: José Antonio
authors: JA
authors: López-Guerrero
authors: Ana
authors: A
authors: Calatrava Fons
authors: Zaida
authors: Z
authors: García-Casado
authors: Vicente
authors: V
authors: Alapont Olavarrieta
authors: Jorge
authors: J
authors: Campos Máñez
authors: Carlos
authors: C
authors: Vázquez Albaladejo
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D053842:Microsatellite Instability; D018895:Microsatellite Repeats / Q000235:genetics; D008875:Middle Aged; D011379:Prognosis
chemical_list: D014408:Biomarkers, Tumor