title: Significant variation of immunohistochemical marker expression in paired primary and metastatic clear cell renal cell carcinomas.
abstract: OBJECTIVE
  To compare the immunohistochemical expression of diagnostic markers in primary clear cell renal cell carcinomas (RCCs) and their matched metastases.
  
  
  METHODS
  Tissue microarrays were constructed from 15 pairs of primary and metastatic clear cell RCCs and then evaluated for the immunohistochemical expression of renal cell carcinoma antigen (RCCA), kidney-specific cadherin, carbonic anhydrase IX (CAIX), and paired box genes 2 (PAX2) and 8 (PAX8).
  
  
  RESULTS
  There was significantly higher overall marker expression in metastatic tumors compared to their matched primaries (P < .001). Individually, there was greater CAIX, PAX2, and PAX8 expression and lower RCCA expression in metastatic tumors. Most importantly, a significant proportion of originally RCCA-positive tumors lost such expression in metastases.
  
  
  CONCLUSIONS
  Metastatic RCCs have significantly higher expression of PAX2 and PAX8 compared to primary RCCs. RCCA is not very reliable in this diagnostic setting, both because of its lower overall sensitivity and loss of expression in metastatic RCCs.
authors: Department of Pathology, University of Colorado Medical Center, Aurora, CO, USA.
authors: Zenggang
authors: Z
authors: Pan
authors: William
authors: W
authors: Grizzle
authors: Omar
authors: O
authors: Hameed
mesh_terms: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor / Q000378:metabolism; D015820:Cadherins / Q000378:metabolism; D000071231:Carbonic Anhydrase IX; D002256:Carbonic Anhydrases / Q000378:metabolism; D002292:Carcinoma, Renal Cell / Q000378:metabolism* / Q000473:pathology / Q000556:secondary; D006801:Humans; D007680:Kidney Neoplasms / Q000378:metabolism* / Q000473:pathology; D051762:PAX2 Transcription Factor / Q000378:metabolism; D000072636:PAX8 Transcription Factor; D051761:Paired Box Transcription Factors / Q000378:metabolism; D000067759:Receptor for Advanced Glycation End Products / Q000378:metabolism
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D015820:Cadherins; D051762:PAX2 Transcription Factor; C497318:PAX2 protein, human; D000072636:PAX8 Transcription Factor; C083325:PAX8 protein, human; D051761:Paired Box Transcription Factors; D000067759:Receptor for Advanced Glycation End Products; C089226:CA9 protein, human; D000071231:Carbonic Anhydrase IX; D002256:Carbonic Anhydrases
keywords: Carbonic anhydrase IX; Immunohistochemistry; Kidney-specific cadherin; Metastatic clear cell renal cell carcinoma; Paired box gene 2; Paired box gene 8; RCC antigen; Renal markers