title: Neoadjuvant therapy in rectal cancer.
abstract: BACKGROUND
  The optimal type of neoadjuvant therapy regimen in rectal cancer is contentious.
  
  
  OBJECTIVE
  This study aimed to review the impact of neoadjuvant therapy on oncological outcomes and complications (short and long term) in patients undergoing total mesorectal excision for rectal cancer.
  
  
  METHODS
  An electronic search of MEDLINE, PubMed, EMBASE, and the Cochrane Database of Collected Reviews was performed through March 2010.
  
  
  METHODS
  Key-word combinations including rectal cancer, total mesorectal excision, radiotherapy, chemotherapy, endorectal ultrasound, and magnetic resonance imaging were used to identify randomized control trials where chemotherapy and/or radiotherapy were deployed before resectional surgery.
  
  
  METHODS
  Patients underwent total mesorectal excision for rectal cancer who did and did not receive preoperative chemotherapy and/or radiotherapy.
  
  
  METHODS
  The main outcome measures comprised the impact of the addition of neoadjuvant therapy to total mesorectal excision on the perioperative complication rate, the pathological complete response rate, the rate of local recurrence, and long-term treatment-related complications.
  
  
  RESULTS
  A total of 12 randomized control trials involving 9410 patients were included. Both short-course radiotherapy and long-course chemoradiation can offer a relative risk reduction of 50% in local recurrence in appropriately selected patients with stage II and III rectal cancer. This oncological benefit comes at the cost of a relative risk increase of 50% in both acute treatment-related toxicity and long-term anorectal dysfunction.
  
  
  CONCLUSIONS
  Preoperative staging provides only an estimate of the "true" tumor stage that can only be determined by histological assessment of the tumor specimen which renders appropriate patient selection challenging.
  
  
  CONCLUSIONS
  The current treatment trade-off of a relative risk reduction of local recurrence of 50% at the cost of a relative increase of 50% in treatment-related complications underpins the need for more accurate patient staging and more precise delivery of neoadjuvant therapy.
authors.affiliation: Division of Colorectal Surgery, University of Rochester Medical Center, Rochester, New York 14642, USA. fergal_fleming@URMC.rochester.edu
authors.forename: Fergal J
authors.initials: FJ
authors.lastname: Fleming
authors.forename: Lars
authors.initials: L
authors.lastname: Påhlman
authors.forename: John R T
authors.initials: JR
authors.lastname: Monson
mesh_terms: D006801:Humans; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D012004:Rectal Neoplasms / Q000473:pathology / Q000628:therapy*; D016896:Treatment Outcome