title: Immunohistochemical expression of CD44s in renal cell carcinoma lacks independent prognostic significance.
abstract: OBJECTIVE
  To analyze the immunohistochemical expression of the standard isoform of CD44 (CD44s) adhesion molecule in clear cell renal cell carcinoma (CCRCC) and its impact on clinical outcomes.
  
  
  METHODS
  Ninety-nine consecutive patients treated surgically for RCC between 1992 and 2009 were selected. A single pathologist reviewed all cases to effect a uniform reclassification and determine the most representative tumor areas for construction of a tissue microarray. The same pathologist, who was blinded to the outcome of the cases, semi-quantitatively scored the staining intensity of CD44s in all specimens. The counting was done using the H-Score algorithm.
  
  
  RESULTS
  Of the 99 immunostained RCC specimens, 57(57.7 %) showed low expression, and 42(42.4 %) showed high expression levels of CD44s. The expression of CD44s was directly associated with tumor size (p = 0.03), clinical stage (p = 0.02) and Fuhrman grade (p = 0.02). Disease specifi c survival (DSS) rates for patients whose specimens expressed low and high levels of CD44s was 88.1 % and 67.5 %, respectively (p = 0.009). Progression free survival (PFS) rates in patients with low and high expression of CD44s were 78.8 % and 61.7 %, respectively (p = 0.05). Classical features such as the presence of metastasis and clinical stage remained isolated predictors of survival.
  
  
  CONCLUSIONS
  Immunohistochemical expression of CD44s was associated with important clinical variables such as stage and Fuhrman grade. However, it was not an independent predictor of survival. Therefore, we believe it has a limited role as a prognostic marker in patients with CCRCC.
authors.affiliation: A.C. Camargo Hospital, Sao Paulo, Brazil.
authors.forename: Walter Henriques da
authors.initials: WH
authors.lastname: Costa
authors.forename: Rafael Malagoli
authors.initials: RM
authors.lastname: Rocha
authors.forename: Isabela Werneck da
authors.initials: IW
authors.lastname: Cunha
authors.forename: Gustavo Cardoso
authors.initials: GC
authors.lastname: Guimaraes
authors.forename: Stenio de Cássio
authors.initials: Sde C
authors.lastname: Zequi
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D002292:Carcinoma, Renal Cell / Q000737:chemistry / Q000276:immunology* / Q000473:pathology; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D018960:Hyaluronan Receptors / Q000032:analysis*; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D017678:Sex Distribution; D013997:Time Factors; D046888:Tissue Array Analysis
chemical_list: D014408:Biomarkers, Tumor; C473647:CD44S antigen; D018960:Hyaluronan Receptors