title: Correlation of monoclonal and polyclonal somatostatin receptor 5 antibodies in pancreatic neuroendocrine tumors.
abstract: OBJECTIVE
  To evaluate the frequency of somatostatin-receptor 5 (SSTR 5) in pancreatic neuroendocrine tumors by using monoclonal and polyclonal antibodies.
  
  
  METHODS
  we analyzed 66 proven pancreatic neuroendocrine tumors immunohistochemically with monoclonal (clone UMB-4) and polyclonal SSTR 5-antibodies. Immunoreactive score (IRS) and DAKO-score Her2/neu were evaluated.
  
  
  RESULTS
  Immunohistochemistry analysis demonstrated for the IRS a significant higher staining of all specimen using the monoclonal antibodies ( IRS SSTR5 poly vs IRS SSTR 5 mono; 20.0% vs 30.3% p < 0.001) by a correlation of 0.21; p = 0.04. For the HER2 score there was also a significant higher staining in the monoclonal group (Her2 SSTR 5 poly vs Her2 SSTR 5 mono; 21.5% vs 28.8% p < 0.001) by a correlation of 0.20; p = 0.08.
  
  
  CONCLUSIONS
  Both antibodies are useful in staining of SSTR, although UMB-4 demonstrated a 10% higher SSTR 5 staining. Due to the previous underestimated expression rate of SSTR 5, current standards in diagnostics and therapy should be reconsidered. The increasing usage of long-acting pansomatostatin receptor analogues will rise the adverse effects connected to SSTR5 binding.
authors.affiliation: Department of General and Visceral Surgery, Zentralklinik Bad Berka Bad Berka, Germany. Daniel.Kaemmerer@zentralklinik.de
authors.forename: Daniel
authors.initials: D
authors.lastname: Kaemmerer
authors.forename: Amelie
authors.initials: A
authors.lastname: Lupp
authors.forename: Luisa
authors.initials: L
authors.lastname: Peter
authors.forename: Elke
authors.initials: E
authors.lastname: Fischer
authors.forename: Stefan
authors.initials: S
authors.lastname: Schulz
authors.forename: Günter
authors.initials: G
authors.lastname: Klöppel
authors.forename: Merten
authors.initials: M
authors.lastname: Hommann
mesh_terms: D000911:Antibodies, Monoclonal; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D018358:Neuroendocrine Tumors / Q000378:metabolism*; D010190:Pancreatic Neoplasms / Q000378:metabolism*; D017481:Receptors, Somatostatin / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D017481:Receptors, Somatostatin; C094573:somatostatin receptor 5