title: Could vitamin D sufficiency improve the survival of colorectal cancer patients?
abstract: OBJECTIVE
  To determine whether a higher serum 25-hydroxyvitamin D [25(OH)D] concentration at diagnosis is associated with longer survival of colorectal cancer patients.
  
  
  METHODS
  A meta-analysis was performed of studies of the relationship between 25(OH)D and mortality of patients with colorectal cancer. A random-effects model was used to calculate a pooled hazards ratio. Homogeneity was evaluated through a DerSimonian-Laird test.
  
  
  RESULTS
  Higher serum concentrations of 25(OH)D were associated with lower mortality in patients with colorectal cancer. Patients in the highest quintile of 25(OH)D had 37% lower mortality from colorectal cancer compared to those in the lowest quintile of 25(OH)D (pooled odds ratio=0.63, p<0.0001). Dose-response curves showed lower hazard ratios for mortality with higher serum 25(OH)D through at least 40ng/ml. There were no exceptions.
  
  
  CONCLUSIONS
  Higher serum 25(OH)D was associated with lower mortality of patients with colorectal cancer. These results suggest that colorectal cancer patients with deficient levels of serum 25(OH)D should have their levels restored to a normal range (30-80ng/ml). This could be done with regular testing of serum 25(OH)D to be confident that an adequate serum level is being maintained. Additional studies would be worthwhile to evaluate confounding or the possibility of reverse causation.
authors.affiliation: Department of Family and Preventive Medicine 0620, University of California, San Diego, La Jolla CA 92093, USA.
authors.forename: Sharif B
authors.initials: SB
authors.lastname: Mohr
authors.affiliation: Department of Family and Preventive Medicine 0620, University of California, San Diego, La Jolla CA 92093, USA.
authors.forename: Edward D
authors.initials: ED
authors.lastname: Gorham
authors.affiliation: Department of Family and Preventive Medicine 0620, University of California, San Diego, La Jolla CA 92093, USA.
authors.forename: June
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Medicine, Internal Medical Group, University of California, San Diego, La Jolla CA 92093, USA.
authors.forename: Heather
authors.initials: H
authors.lastname: Hofflich
authors.affiliation: Department of Medicine, Division Global Health, University of California, San Diego, La Jolla CA 92093, USA; Graduate School of Public Health, San Diego State University, San Diego CA 92182, USA. Electronic address: raphael.e.cuomo@gmail.com.
authors.forename: Raphael E
authors.initials: RE
authors.lastname: Cuomo
authors.affiliation: Department of Family and Preventive Medicine 0620, University of California, San Diego, La Jolla CA 92093, USA.
authors.forename: Cedric F
authors.initials: CF
authors.lastname: Garland
mesh_terms: D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000401:mortality*; D006801:Humans; D011379:Prognosis; D015996:Survival Rate; D014807:Vitamin D / Q000627:therapeutic use*; D014815:Vitamins / Q000627:therapeutic use*
chemical_list: D014815:Vitamins; D014807:Vitamin D
keywords: Colon cancer; Incidence; Meta-analysis; Vitamin D