Immunohistochemical evidence for mesothelial origin of paratesticular adenomatoid tumour

Histopathology. 2000 Feb;36(2):109-15. doi: 10.1046/j.1365-2559.2000.00825.x.


Aims: To investigate the histogenesis of paratesticular adenomatoid tumour by use of immunohistochemical markers for a variety of carcinomas and mesothelioma.

Methods and results: Immunohistochemical staining of sections from 12 cases of paratesticular adenomatoid tumour was undertaken using primary antibodies to antigens expressed by benign epithelial cells and carcinoma (cytokeratin AE1/AE3, cytokeratin 34ssE12, epithelial membrane antigen, MOC-31, Ber-EP4, CEA, B72.3, LEA.135, Leu M1), stromal and vascular markers (vimentin, CD34, factor VIII), and mesothelioma-associated antigens (thrombomodulin, HBME-1, OC 125) and p53 protein. There was absence of immunohistochemical expression of epithelial/carcinoma markers MOC-31, Ber-EP4, CEA, B72.3, LEA.135, Leu M1 and to factor VIII and CD34. All tumours expressed cytokeratin AE1/AE3, epithelial membrane antigen and vimentin, with weak expression of cytokeratin 34ssE12 in 25% of tumours. Each tumour showed expression of thrombomodulin, HBME-1 and OC 125 in a membranous distribution. p53 protein expression was not detected.

Conclusions: The immunohistochemical profile of paratesticular adenomatoid tumour is strongly supportive of a mesothelial cell origin.

MeSH terms

  • Adenomatoid Tumor / metabolism
  • Adenomatoid Tumor / pathology*
  • Biomarkers, Tumor / analysis
  • CA-125 Antigen / analysis
  • Humans
  • Immunohistochemistry
  • Keratins / analysis
  • Male
  • Mesothelioma / metabolism
  • Mesothelioma / pathology*
  • Mucin-1 / analysis
  • Testicular Neoplasms / metabolism
  • Testicular Neoplasms / pathology*
  • Testis / chemistry
  • Testis / pathology
  • Thrombomodulin / analysis
  • Vimentin / analysis


  • Biomarkers, Tumor
  • CA-125 Antigen
  • Mucin-1
  • Thrombomodulin
  • Vimentin
  • Keratins