title: Visceral obesity, muscle mass and outcome in rectal cancer surgery after neo-adjuvant chemo-radiation.
abstract: BACKGROUND
  Preoperative chemoradiation has become a routine modality in the treatment of rectal carcinoma that may impair a patients general condition. In these patients, it is important to identify factors that influence postoperative recovery. Visceral obesity(VO) as a metabolic risk factor was studied in rectal cancer patients receiving preoperative chemoradiation.
  
  
  OBJECTIVE
  The impact of VO on post-operative outcome in rectal carcinoma surgery after preoperative chemoradiation was studied. In addition, the effect of chemoradiation on body composition was studied.
  
  
  METHODS
  The visceral fat area(VFA), total fat area(TFA) and skeletal muscle area(SMA) were measured on cross-sectional CT-slides in 74 patients who underwent rectal cancer surgery after chemoradiation. CT-scans taken before and after chemoradiation were analysed. Associations between VFA, per- and postoperative complications were studied. A VFA of 100 cm(2) and 130 cm(2) was used to differentiate between non-VO and VO.
  
  
  RESULTS
  Using a VO cut-off point of a VFA of 100 cm(2), the VO patients had more per-operative blood loss(471 mL vs 271 mL p = 0.020), a higher complication rate(10% vs 49% p = 0.001), more ileus(2% vs 28% p = 0.027) and a longer length of stay(9.7days vs 13days p = 0.027). When a VFA of 130 cm(2) was used, VO patients showed more complications(17% vs 55%, p = 0.001) and ileus(10% vs 32% p = 0.017). During chemoradiation the SMA increased(Mean difference: 2.2 cm(2) p = 0.024), while the VFA showed no change.
  
  
  CONCLUSIONS
  It appears that VO is associated with co-morbidity and poor outcome in rectal cancer patients. Using different cutoff values for VO different associations with outcome were found. SMA increased during chemoradiation, a phenomenon that remains to be explained.
authors.affiliation: Department of Surgery, Medical Center Alkmaar, The Netherlands.
authors.forename: Colin
authors.initials: C
authors.lastname: Heus
authors.affiliation: Department of Surgery, Medical Center Alkmaar, The Netherlands.
authors.forename: Hamit
authors.initials: H
authors.lastname: Cakir
authors.affiliation: Department of Surgery, Medical Center Alkmaar, The Netherlands.
authors.forename: Arjan
authors.initials: A
authors.lastname: Lak
authors.affiliation: Trial Center Holland Health, Alkmaar, The Netherlands.
authors.forename: Hiëronymus J
authors.initials: HJ
authors.lastname: Doodeman
authors.affiliation: Department of Surgery, Medical Center Alkmaar, The Netherlands; Trial Center Holland Health, Alkmaar, The Netherlands. Electronic address: a.p.j.houdijk@mca.nl.
authors.forename: Alexander P J
authors.initials: AP
authors.lastname: Houdijk
mesh_terms: D000328:Adult; D000368:Aged; D016063:Blood Loss, Surgical; D001823:Body Composition; D059186:Chemoradiotherapy, Adjuvant / Q000009:adverse effects*; D005260:Female; D006801:Humans; D045823:Ileus; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology; D056128:Obesity, Abdominal / Q000150:complications* / Q000000981:diagnostic imaging; D011183:Postoperative Complications / Q000209:etiology*; D011184:Postoperative Period; D011351:Proctoscopy / Q000009:adverse effects* / Q000379:methods; D012004:Rectal Neoplasms / Q000473:pathology / Q000628:therapy*; D012189:Retrospective Studies; D012307:Risk Factors; D014057:Tomography, X-Ray Computed
keywords: Abdominal fat; Chemotherapy; Complications; Outcome; Radiation therapy; Rectum surgery; Visceral fat