title: Process of hepatic metastasis from pancreatic cancer: biology with clinical significance.
abstract: OBJECTIVE
  Pancreatic cancer shows a remarkable preference for the liver to establish secondary tumors. Selective metastasis to the liver is attributed to the development of potential microenvironment for the survival of pancreatic cancer cells. This review aims to provide a full understanding of the hepatic metastatic process from circulating pancreatic cancer cells to their settlement in the liver, serving as a basic theory for efficient prediction and treatment of metastatic diseases.
  
  
  METHODS
  A systematic search of relevant original articles and reviews was performed on PubMed, EMBASE and Cochrane Library for the purpose of this review.
  
  
  RESULTS
  Three interrelated phases are delineated as the contributions of the interaction between pancreatic cancer cells and the liver to hepatic metastasis process. Chemotaxis of disseminated pancreatic cancer cells and simultaneous defensive formation of platelets or neutrophils facilitate specific metastasis toward the liver. Remodeling of extracellular matrix and stromal cells in hepatic lobules and angiogenesis induced by proangiogenic factors support the survival and growth of clinical micrometastasis colonizing the liver. The bimodal role of the immune system or prevalence of cancer cells over the immune system makes metastatic progression successfully proceed from micrometastasis to macrometastasis.
  
  
  CONCLUSIONS
  Pancreatic cancer is an appropriate research object of cancer metastasis representing more than a straight cascade. If any of the successive or simultaneous phases, especially tumor-induced immunosuppression, is totally disrupted, hepatic metastasis will be temporarily under control or even cancelled forever. To shrink cancers on multiple fronts and prolong survival for patients, novel oral or intravenous anti-cancer agents covering one or different phases of metastatic pancreatic cancer are expected to be integrated into innovative strategies on the premise of safety and efficacious biostability.
authors.affiliation: Department of Pancreatic Surgery, Pancreatic Disease Institute, Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200040, China.
authors.forename: Haojun
authors.initials: H
authors.lastname: Shi
authors.affiliation: Department of Pancreatic Surgery, Pancreatic Disease Institute, Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200040, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Pancreatic Surgery, Pancreatic Disease Institute, Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200040, China. surgeonf@126.com.
authors.forename: Deliang
authors.initials: D
authors.lastname: Fu
mesh_terms: D006801:Humans; D008113:Liver Neoplasms / Q000276:immunology / Q000473:pathology / Q000556:secondary* / Q000628:therapy; D010190:Pancreatic Neoplasms / Q000276:immunology / Q000473:pathology* / Q000628:therapy
keywords: Angiogenesis; Cell adhesion; Hepatic metastasis; Pancreatic cancer; Remodeling of extracellular matrix; Tumor-induced immunosuppression