title: The role of body composition evaluation by computerized tomography in determining colorectal cancer treatment outcomes: a systematic review.
abstract: BACKGROUND
  Strong evidence indicates that excessive adipose tissue distribution or reduced muscle influence short-, mid-, and long-term colorectal cancer outcomes. Computerized tomography-based body composition (CTBC) analysis quantifies this in a reproducible parameter. We reviewed the evidence linking computerized tomography (CT) based quantification of BC with short and long-term outcomes in colorectal cancer (CRC).
  
  
  METHODS
  A systematic review was performed according to PRISMA guidelines. A literature search was performed by two independent reviewers on all studies that included CTBC analysis in patients undergoing treatment for CRC using Medline, EMBASE, Google Scholar, and Cochrane databases. Outcomes of interest included short-term recovery, oncological outcomes, and survival.
  
  
  RESULTS
  Seventy-five studies were identified; sixteen met the inclusion criteria. None were randomized controlled trials and all were cohort studies of small sample size. Several types of CTBC image analysis software were identified, reporting subcutaneous, visceral and skeletal muscle tissues. Visceral obesity and reduced muscle mass were categorical parameters quantified by CTBC analysis. Due to marked study heterogeneity, quantitative data synthesis was not possible. High visceral adipose tissue and reduced skeletal muscle resulted in poorer short-term recovery (eleven studies), poorer oncological outcomes (six studies), and poorer survival (six studies).
  
  
  CONCLUSIONS
  CTBC techniques may be linked to outcomes in colorectal cancer patients, however larger studies are required. CTBC based assessment may allow early identification of high-risk patients, allowing early optimisation of patients undergoing cancer treatments.
authors.affiliation: Department of Surgery, St. Mark's Hospital, Watford Road, Harrow, Middlesex HA1 3UJ, United Kingdom; Department of Surgery and Cancer, Imperial College, Paddington, London W2 1NY, United Kingdom.
authors.forename: G
authors.initials: G
authors.lastname: Malietzis
authors.affiliation: Department of Colorectal Surgery, The Christie NHS Foundation Trust, Manchester M20 4BX, United Kingdom.
authors.forename: O
authors.initials: O
authors.lastname: Aziz
authors.affiliation: Department of Surgery, St. Mark's Hospital, Watford Road, Harrow, Middlesex HA1 3UJ, United Kingdom; Department of Surgery and Cancer, Imperial College, Paddington, London W2 1NY, United Kingdom.
authors.forename: N M
authors.initials: NM
authors.lastname: Bagnall
authors.affiliation: Department of Clinical and Surgical Sciences, University of Edinburgh, Edinburgh EH16 4SB, United Kingdom.
authors.forename: N
authors.initials: N
authors.lastname: Johns
authors.affiliation: Department of Clinical and Surgical Sciences, University of Edinburgh, Edinburgh EH16 4SB, United Kingdom.
authors.forename: K C
authors.initials: KC
authors.lastname: Fearon
authors.affiliation: Department of Surgery, St. Mark's Hospital, Watford Road, Harrow, Middlesex HA1 3UJ, United Kingdom; Department of Surgery and Cancer, Imperial College, Paddington, London W2 1NY, United Kingdom. Electronic address: i.jenkins@nhs.net.
authors.forename: J T
authors.initials: JT
authors.lastname: Jenkins
mesh_terms: D050154:Adiposity; D015179:Colorectal Neoplasms / Q000401:mortality / Q000628:therapy*; D006801:Humans; D050152:Intra-Abdominal Fat; D007902:Length of Stay; D018482:Muscle, Skeletal; D061646:Operative Time; D011183:Postoperative Complications; D055948:Sarcopenia / Q000150:complications; D015996:Survival Rate; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: Body composition; Colorectal cancer; Outcomes