title: Chemotherapy before liver resection of colorectal metastases: friend or foe?
abstract: OBJECTIVE
  We conducted a systematic review of the published literature to critically assess benefits and risks of the use of preoperative chemotherapy in patients presenting with colorectal liver metastases.
  
  
  BACKGROUND
  In many centers, chemotherapy is used before hepatic resection of colorectal metastases, even in the presence of a single lesion. Application of chemotherapy requires clear conceptual distinction between patients presenting with resectable lesions (neoadjuvant) versus patients presenting with unresectable lesions, for which chemotherapy is used to reach a resectable situation (downsizing).
  
  
  METHODS
  The literature (PubMed) was systematically reviewed for publications related to liver surgery and chemotherapy according to the methodology recommended by the Cochrane Collaboration.
  
  
  RESULTS
  For unresectable liver metastases, combination regimens result in enhanced tumor response and resectability rates up to 30%, although the additional benefit from targeted agents such as bevacizumab or cetuximab is marginal. For resectable lesions, studies on neoadjuvant chemotherapy failed to convincingly demonstrate a survival benefit. Most reports described increased postoperative complications in a subset of patients due to parenchymal alterations such as chemotherapy-associated steatohepatitis or sinusoidal obstruction syndrome.
  
  
  CONCLUSIONS
  Preoperative standard chemotherapy can be recommended for downsizing unresectable liver metastases, but not for resectable lesions, for which adjuvant chemotherapy is preferred.
authors: Swiss Hepato-Pancreato-Biliary (HPB) Center, Department of Surgery, University Hospital Zurich, Zurich, Switzerland.
authors: Kuno
authors: K
authors: Lehmann
authors: Andreas
authors: A
authors: Rickenbacher
authors: Achim
authors: A
authors: Weber
authors: Bernhard C
authors: BC
authors: Pestalozzi
authors: Pierre-Alain
authors: PA
authors: Clavien
mesh_terms: D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D056486:Chemical and Drug Induced Liver Injury; D017024:Chemotherapy, Adjuvant; D015179:Colorectal Neoplasms / Q000401:mortality / Q000473:pathology*; D006498:Hepatectomy; D006801:Humans; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000556:secondary / Q000601:surgery*; D020360:Neoadjuvant Therapy; D011183:Postoperative Complications / Q000453:epidemiology; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents