title: [Characterisation and differentiation of chondroblastomas and chondromyxoidfibromas - presence and expression of collagen types I and II].
abstract: OBJECTIVE
  Chondroblastomas and chondromyxoidfiibromas are rare benign skeletal neoplasms with reported overlapping histology. Aim of this study was to analyse the biochemical composition of the matrix of these tumour entities in order to further characterise the cellular phenotypes of these neoplasms using typical cell biological marker genes.
  
  
  METHODS
  The matrix compositions of chondroblastomas and chondromyxoidfibromas were analyzed by HE-histology, histochemistry, and immunolocalization techniques. Cellular gene expression patterns were detected by mRNA in situ hybridization.
  
  
  RESULTS
  Chondroblastomas are rich in collagen type I and show foci of an osteoid-like matrix, whereas collagen type II as a typical marker of chondrocytic differentiation was not detected in any of the specimens. Chondromyxoidfiibromas had foci of chondroid appearance with chondroblastic cellular differentiation characterised by collagen type II expression.
  
  
  CONCLUSIONS
  These results characterise chondroblastomas and chondromyxoidfiibromas as skeletal neoplasms that have a different biology and which can be distinguished by matrix protein expression products: collagen type II, the typical marker of chondroblast differentiation, could only be detected in chondromyxoidfibromas, but not in chondroblastomas. Thus, both neoplasms are clearly different on the cell biological level.
authors.affiliation: Pathologisches Institut, Universität Erlangen-Nürnberg, Erlangen, Germany.
authors.forename: C M
authors.initials: CM
authors.lastname: Schörle
authors.forename: C
authors.initials: C
authors.lastname: Inwards
authors.forename: K K
authors.initials: KK
authors.lastname: Unni
authors.forename: T
authors.initials: T
authors.lastname: Kirchner
authors.forename: T
authors.initials: T
authors.lastname: Aigner
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D001859:Bone Neoplasms / Q000473:pathology*; D001842:Bone and Bones / Q000473:pathology; D002804:Chondroblastoma / Q000473:pathology*; D002812:Chondroma / Q000473:pathology*; D024042:Collagen Type I / Q000032:analysis*; D024043:Collagen Type II / Q000032:analysis*; D003937:Diagnosis, Differential; D006801:Humans
chemical_list: D014408:Biomarkers, Tumor; D024042:Collagen Type I; D024043:Collagen Type II