title: Surgery of Colorectal Liver Metastases: Pushing the Limits.
abstract: BACKGROUND
  The recent advent of more effective chemotherapy and the development of surgical procedures have expanded the pool of resectable patients with colorectal liver metastases (CLM). Two-stage hepatectomy (TSH), associated liver partition and portal vein ligation for staged hepatectomy (ALPPS), and ultrasound-guided enhanced one-stage hepatectomy (e-OSH) are the surgical solutions proposed for these patients, but the range of indications for these procedures vary from institution to institution.
  
  
  CONCLUSIONS
  The advantages and disadvantages of each approach are herein discussed. Patients who drop out between the staged operations of TSH limit its success rate, although predictive scores may help with patient selection and thereby optimize the results. Safety and oncological suitability are concerns to be addressed when considering ALPPS. These concerns notwithstanding, ALPPS has introduced an innovative concept in surgery: the monosegmental remnant liver. Studies involving e-OSH have proven the oncological suitability of tumor exposure once the CLM is detached from major intrahepatic vessels. This finding could expand the indications for e-OSH, although the technical challenges that it entails limit its spread among the surgical community. The liver-first approach involves the clearance of tumors from the liver before the colorectal primary is tackled. This approach fully justifies the complexity of e-OSH.
  
  
  CONCLUSIONS
  Predictive scores limiting the interstage dropout of TSH, partial and monosegmental ALPPS, and R1 vascular e-OSH justified by solid long-term results represent new insights that could help refne the patient assignment to each of these approaches. Additionally, liver transplantation is an emerging treatment for CLM that should be taken into account.
authors.affiliation: Department of Surgery, Division of Hepatobiliary and General Surgery, Humanitas University, Hu-manitas Clinical and Research Hospital, Rozzano, Italy.
authors.forename: Guido
authors.initials: G
authors.lastname: Torzilli
authors.affiliation: Centre Hépato-Biliaire, AP-HP, Hôpital Universitaire Paul Brousse, Villejuif, France.
authors.forename: René
authors.initials: R
authors.lastname: Adam
authors.affiliation: Department of Surgery, Division of Hepatobiliary and General Surgery, Humanitas University, Hu-manitas Clinical and Research Hospital, Rozzano, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Viganò
authors.affiliation: Centre Hépato-Biliaire, AP-HP, Hôpital Universitaire Paul Brousse, Villejuif, France.
authors.forename: Katsunori
authors.initials: K
authors.lastname: Imai
authors.affiliation: Department of General Surgery, Division of Hepatobiliary and Pancreatic Surgery, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Jeremias
authors.initials: J
authors.lastname: Goransky
authors.affiliation: Department of Surgery, Division of Hepatobiliary and General Surgery, Humanitas University, Hu-manitas Clinical and Research Hospital, Rozzano, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Fontana
authors.affiliation: Department of Visceral and Transplantation Surgery, University Hospitals of Geneva, Geneva, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Toso
authors.affiliation: Department of Visceral and Transplantation Surgery, University Hospitals of Geneva, Geneva, Switzerland.
authors.forename: Pietro
authors.initials: P
authors.lastname: Majno
authors.affiliation: Department of General Surgery, Division of Hepatobiliary and Pancreatic Surgery, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Eduardo
authors.initials: E
authors.lastname: de Santibañes
keywords: Complications; Metastasis; Outcome; Surgery; Systemic chemotherapy