title: Superiority of extended neoadjuvant chemotherapy with gemcitabine in pancreatic cancer: a comparative analysis in a clinically adapted orthotopic xenotransplantation model in SCID beige mice.
abstract: BACKGROUND
  Intensive efforts are being made to develop new approaches for adjuvant or neoadjuvant treatment in pancreas carcinoma. Recently, we established an animal model simulating an adjuvant therapeutic treatment setting. In order to additionally mimic a neoadjuvant treatment regime, we further developed the preclinical testing system.
  
  
  METHODS
  Subtotal pancreatectomy was performed in mice after orthotopic inoculation of human pancreatic cancer cells (PancTu1). Four different settings were investigated: control without chemotherapy, adjuvant, neoadjuvant and extended neoadjuvant treatment protocols employing gemcitabine. All animals were autopsied 28 days after tumor resection.
  
  
  RESULTS
  28 of 32 animals survived the treatment setting. The largest pancreatic tumor masses were seen in animals without any chemotherapy, and the different chemotherapy protocols resulted in a stepwise reduction of the tumor mass. The mean weight of locally recurrent tumors was 553.1 +/- 133.2 mg (control) and 44 +/- 21.8 mg (adjuvant treatment group). Animals in the neoadjuvant treatment group developed larger tumor masses (215 +/- 191.3 mg) but fewer organ metastases. An extended neoadjuvant treatment setting proved to be most effective, resulting in the smallest tumor masses (25.6 +/- 8.8 mg) and the fewest organ metastases.
  
  
  CONCLUSIONS
  Murine orthotopic tumor resection is an excellent simulation of the clinical situation and therefore provides a relevant option for preclinical comparative testing of new therapeutic strategies. To our knowledge, this is the first model described, in which all different therapeutic regimes for pancreatic carcinoma were systematically compared with each other in a standardized manner. The extended neoadjuvant regime proved to be superior.
authors: Department of General Surgery and Thoracic Surgery, University Hospital of Schleswig-Holstein Campus, Kiel, Germany.
authors: Jan-Hendrik
authors: JH
authors: Egberts
authors: Bodo
authors: B
authors: Schniewind
authors: Bence
authors: B
authors: Sipos
authors: Sebastian
authors: S
authors: Hinz
authors: Holger
authors: H
authors: Kalthoff
authors: Jürgen
authors: J
authors: Tepel
mesh_terms: D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use*; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D004195:Disease Models, Animal; D051379:Mice; D016513:Mice, SCID; D020360:Neoadjuvant Therapy / Q000379:methods*; D009368:Neoplasm Transplantation; D010180:Pancreatectomy; D010190:Pancreatic Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery; D014183:Transplantation, Heterologous; D000093542:Gemcitabine
chemical_list: D000964:Antimetabolites, Antineoplastic; D003841:Deoxycytidine; D000093542:Gemcitabine