title: Surgical resection of primary tumour improves aerobic performance in colorectal cancer.
abstract: BACKGROUND
  Colorectal cancer is the third most common cancer in the UK, with patients suffering declines in muscle mass and aerobic function. We hypothesised that tumour removal in non-metastatic colorectal cancer would lead to a restoration of lean muscle mass and increases in objective and subjective measures of aerobic performance.
  
  
  METHODS
  We recruited two groups: patients with colorectal cancer (n = 30, 65.3 (51-77) y, body mass index 27.67 (4.83) kg m(-2)) and matched controls (n = 30, 64.6 (42-77) y, BMI 27.14 (3.51) kg m(-2)). Controls underwent a single study while colorectal cancer patients were studied before and 10 months after tumour resection. Aerobic performance was assessed via cardiopulmonary exercise testing and activity questionnaires. Lean muscle mass was measured via dual-energy X-ray absorptiometry.
  
  
  RESULTS
  Lean muscle mass was not different between groups (control: 47.82 (8.23); pre-resection: 52.41 (10.59); post-resection: 52.38 (10.52), kg). Anaerobic threshold was lower in pre-operative patients compared to controls (14.40 (3.23) vs. 19.67 (5.81) ml kg(-1) min(-1), p < 0.0001), increasing significantly post-resection (17.00 (3.56) ml kg(-1) min(-1)p < 0.0001). Self reported maximal physical activity was lower after resection compared to preoperatively (pre-resection 6.0 (6.5-5 IQR), post-resection 3.75 (4-3 IQR), p < 0.0001).
  
  
  CONCLUSIONS
  In colorectal cancer, anaerobic threshold is reached more rapidly than in matched controls, returning toward normal with tumour resection. Self-reported measures of activity do not mirror this objective change, cardiopulmonary exercise testing may therefore allow for a more accurate evaluation of pre and postoperative performance capability. The variance between objective and subjective measures of exercise capacity may be important in determining return to normal activities.
authors: Division of Surgery, School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby DE22 3DT, UK; MRC/Arthritis Research UK Centre for Musculoskeletal Ageing Research, University of Nottingham, NG7 2UH, UK.
authors: J P
authors: JP
authors: Williams
authors: Division of Surgery, School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby DE22 3DT, UK. Electronic address: murthy.nyasavajjala@nhs.net.
authors: S M
authors: SM
authors: Nyasavajjala
authors: School of Biomedical Sciences, Queens Medical Centre, Nottingham NG7 2UH, UK; MRC/Arthritis Research UK Centre for Musculoskeletal Ageing Research, University of Nottingham, NG7 2UH, UK.
authors: B E
authors: BE
authors: Phillips
authors: Division of Surgery, School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby DE22 3DT, UK.
authors: M
authors: M
authors: Chakrabarty
authors: Division of Surgery, School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby DE22 3DT, UK; MRC/Arthritis Research UK Centre for Musculoskeletal Ageing Research, University of Nottingham, NG7 2UH, UK.
authors: J N
authors: JN
authors: Lund
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000368:Aged; D015308:Anaerobic Threshold; D001823:Body Composition; D015992:Body Mass Index; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000601:surgery*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal; D016896:Treatment Outcome
keywords: Aerobic performance; Colorectal cancer; Surgery