title: Cytoreductive surgery in combination with hyperthermic intraperitoneal chemotherapy improves survival in patients with colorectal peritoneal metastases compared with systemic chemotherapy alone.
abstract: BACKGROUND
  Colorectal cancer peritoneal metastasis (CPM) confers an exceptionally poor prognosis, and traditional treatment involving systemic chemotherapy (SC) is largely ineffective. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is increasingly advocated for selected patients with CPM; however, opinions are divided because of the perceived lack of evidence, high morbidity, mortality, and associated costs for this approach. As there is no clear consensus, the aim of this study was to compare outcomes following CRS+HIPEC vs SC alone for CPM using meta-analytical methodology, focusing on survival outcomes. Secondary outcomes assessed included morbidity, mortality, quality of life (QOL), and health economics (HE).
  
  
  METHODS
  An electronic literature search was conducted to identify studies comparing survival following CRS+HIPEC vs SC for CPM. The odds ratio (OR) was calculated using the Mantel-Haenszel method with corresponding 95% confidence intervals (CI) and P-values. Heterogeneity was examined using the Q-statistic and quantified with I(2). The fixed-effect model (FEM) was used in the absence of significant heterogeneity. For included studies, 2- and 5-year survival was compared for CRS+HIPEC vs SC alone.
  
  
  RESULTS
  Four studies (three case-control, one RCT) provided comparative survival data for patients undergoing CRS+HIPEC (n=187) vs SC (n=155) for CPM. Pooled analysis demonstrated superior 2-year (OR 2.78; 95% CI 1.72-4.51; P=0.001) and 5-year (OR 4.07; 95% CI 2.17-7.64; P=0.001) survival with CRS+HIPEC compared with SC. Mortality ranged from 0 to 8%. No data were available for the assessment of QOL or HE.
  
  
  CONCLUSIONS
  Although limited by between-study heterogeneity, the data support the assertion that in carefully selected patients, multimodal treatment of CPM with CRS+HIPEC has a highly positive prognostic impact on medium- and long-term survival compared with SC alone. There is a paucity of comparative data available on morbidity, QOL, and HE.
authors.affiliation: Section of Biosurgery and Surgical Technology, Department of Surgery and Cancer, Imperial College London, St Mary's Hospital, 10th Floor QEQM Building, London W2 1NY, UK.
authors.forename: R
authors.initials: R
authors.lastname: Mirnezami
authors.affiliation: Peritoneal Surface Malignancy Unit, Department of Surgical Oncology, The Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, Amsterdam 1066 CX, The Netherlands.
authors.forename: A M
authors.initials: AM
authors.lastname: Mehta
authors.affiliation: Peritoneal Malignancy Institute, Basingstoke and North Hampshire Hospital, Aldermaston Road, Basingstoke, Hampshire RG24 9NA, UK.
authors.forename: K
authors.initials: K
authors.lastname: Chandrakumaran
authors.affiliation: Peritoneal Malignancy Institute, Basingstoke and North Hampshire Hospital, Aldermaston Road, Basingstoke, Hampshire RG24 9NA, UK.
authors.forename: T
authors.initials: T
authors.lastname: Cecil
authors.affiliation: Peritoneal Malignancy Institute, Basingstoke and North Hampshire Hospital, Aldermaston Road, Basingstoke, Hampshire RG24 9NA, UK.
authors.forename: B J
authors.initials: BJ
authors.lastname: Moran
authors.affiliation: Peritoneal Malignancy Institute, Basingstoke and North Hampshire Hospital, Aldermaston Road, Basingstoke, Hampshire RG24 9NA, UK.
authors.forename: N
authors.initials: N
authors.lastname: Carr
authors.affiliation: Peritoneal Surface Malignancy Unit, Department of Surgical Oncology, The Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, Amsterdam 1066 CX, The Netherlands.
authors.forename: V J
authors.initials: VJ
authors.lastname: Verwaal
authors.affiliation: Peritoneal Malignancy Institute, Basingstoke and North Hampshire Hospital, Aldermaston Road, Basingstoke, Hampshire RG24 9NA, UK.
authors.forename: F
authors.initials: F
authors.lastname: Mohamed
authors.affiliation: University of Southampton Cancer Sciences Division, Southampton University Hospital NHS Trust, Somers Cancer Research Building, Tremona road, Southampton SO166YD, UK.
authors.forename: A H
authors.initials: AH
authors.lastname: Mirnezami
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use*; D015179:Colorectal Neoplasms / Q000473:pathology / Q000601:surgery / Q000628:therapy*; D003131:Combined Modality Therapy; D065426:Cytoreduction Surgical Procedures; D006801:Humans; D006979:Hyperthermia, Induced; D010534:Peritoneal Neoplasms / Q000556:secondary* / Q000628:therapy
chemical_list: D000970:Antineoplastic Agents