title: Prognostic value of Cathepsin D expression in breast cancer: immunohistochemical assessment and correlation with radiometric assay.
abstract: BACKGROUND
  The prognostic significance of Cathepsin D and optimal methodologies to measure Cathepsin D in breast cancers are controversial.
  
  
  METHODS
  Quantitative (immunoradiometric) and semiquantitative (immunohistochemical) assays for Cathepsin D expression were compared using 25 breast carcinomas. Immunohistochemical Cathepsin D results were derived using 3 different anti-Cathepsin D antibodies and significant associations between immunohistochemical and radiometric Cathepsin D data were observed for each reagent. Immunohistochemical analysis of Cathepsin D expression was performed on nearly 500 fixed-embedded archival breast cancers with long-term patient follow-up using 2 anti-Cathepsin D antibodies (CDR2-11/23, IC11).
  
  
  RESULTS
  The immunohistochemical reagents recognized generally overlapping subsets of Cathepsin D positive tumors (correlation co-efficient 0.54; p = 0.00016). Correlations between Cathepsin D data and clinical, histologic or biologic features differed for each antibody. For the node-negative patient subset, Cathepsin D immunopositivity correlated with erbB-2 and stress-response protein 27 overexpression but not survival. Cathepsin D positivity was associated with subsequent distant metastasis and estrogen receptor positivity in node positive patients. Univariate analysis of all patients suggested that Cathepsin D immunopositivity may be predictive of a reduced metastasis-free but not overall survival. Multivariate analysis, however, failed to confirm an independent prognostic value for Cathepsin D in breast cancer patients.
  
  
  CONCLUSIONS
  These data do not confirm an independent prognostic significance for Cathepsin D using immunohistochemical methods on breast cancers.
authors.affiliation: Department of Pathology, Massachusetts General Hospital & Harvard Medical School, Boston.
authors.forename: P
authors.initials: P
authors.lastname: Eng Tan
authors.forename: C C
authors.initials: CC
authors.lastname: Benz
authors.forename: C
authors.initials: C
authors.lastname: Dollbaum
authors.forename: D H
authors.initials: DH
authors.lastname: Moore
authors.forename: S M
authors.initials: SM
authors.lastname: Edgerton
authors.forename: D T
authors.initials: DT
authors.lastname: Zava
authors.forename: A D
authors.initials: AD
authors.lastname: Thor
mesh_terms: D001943:Breast Neoplasms / Q000737:chemistry* / Q000473:pathology; D002402:Cathepsin D / Q000032:analysis*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007118:Immunoassay; D007150:Immunohistochemistry; D015592:Immunoradiometric Assay; D008207:Lymphatic Metastasis; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis
chemical_list: D002402:Cathepsin D