title: Clinical outcomes of vitamin D deficiency and supplementation in cancer patients.
abstract: Results of recent studies suggest that circulating levels of vitamin D may play an important role in cancer-specific outcomes. The present systematic review was undertaken to determine the prevalence of vitamin D deficiency (<25 nmol/L) and insufficiency (25-50 nmol/L) in cancer patients and to evaluate the association between circulating calcidiol (the indicator of vitamin D status) and clinical outcomes. A systematic search of original, peer-reviewed studies on calcidiol at cancer diagnosis, and throughout treatment and survival, was conducted yielding 4,706 studies. A total of 37 studies met the inclusion criteria for this review. Reported mean blood calcidiol levels ranged from 24.7 to 87.4 nmol/L, with up to 31% of patients identified as deficient and 67% as insufficient. The efficacy of cholecalciferol supplementation for raising the concentration of circulating calcidiol is unclear; standard supplement regimens of <1,000 IU D₃ /day may not be sufficient to maintain adequate concentrations or prevent decreasing calcidiol. Dose-response studies linking vitamin D status to musculoskeletal and survival outcomes in cancer patients are lacking.
authors.affiliation: School of Public Health and Social Work, Queensland University of Technology, Brisbane, Queensland, Australia; Department of Nutrition and Dietetics, Princess Alexandra Hospital, Brisbane, Queensland, Australia.
authors.forename: Laisa
authors.initials: L
authors.lastname: Teleni
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Baker
authors.forename: Bogda
authors.initials: B
authors.lastname: Koczwara
authors.forename: Michael G
authors.initials: MG
authors.lastname: Kimlin
authors.forename: Euan
authors.initials: E
authors.lastname: Walpole
authors.forename: Kathy
authors.initials: K
authors.lastname: Tsai
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Isenring
mesh_terms: D002112:Calcifediol / Q000097:blood* / Q000627:therapeutic use; D002762:Cholecalciferol / Q000097:blood / Q000627:therapeutic use; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D006801:Humans; D009369:Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000209:etiology; D016896:Treatment Outcome; D014807:Vitamin D / Q000097:blood / Q000627:therapeutic use; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology*
chemical_list: D014807:Vitamin D; D002762:Cholecalciferol; D002112:Calcifediol
keywords: 25-hydroxyvitamin D; cancer; cancer-specific outcomes; cholecalciferol; vitamin D deficiency