title: Chemotherapy is linked to severe vitamin D deficiency in patients with colorectal cancer.
abstract: BACKGROUND
  Preclinical and clinical evidence support an association between vitamin D deficiency and an increased risk of colorectal cancer. Normal vitamin D status has been linked to favorable health outcomes ranging from decreased risk of osteoporosis to improved cancer mortality. We performed a retrospective study to assess the impact of metastatic disease and chemotherapy treatment on vitamin D status in patients with colorectal cancer residing in Western New York.
  
  
  METHODS
  Patients, 315, with colorectal cancer treated in a single institute were assayed for 25-OH vitamin D. The association of age, gender, primary disease site and stage, body mass index, and chemotherapy with vitamin D status was investigated.
  
  
  RESULTS
  Vitamin D deficiency was common among participants with a median 25-OH vitamin D level of 21.3 ng/ml (optimal range 32-100 ng/ml). Primary site of disease and chemotherapy status were associated with very low 25-OH vitamin D levels (< or =15 ng/ml) on multivariate analysis. Patients receiving chemotherapy and patients with a rectal primary were 3.7 and 2.6-fold more likely to have severe vitamin D deficiency on multivariate analysis than nonchemotherapy patients and colon cancer primary patients, respectively.
  
  
  CONCLUSIONS
  Chemotherapy is associated with a significant increase in the risk of severe vitamin D deficiency. Patients with colorectal cancer, especially those receiving chemotherapy, should be considered for aggressive vitamin D replacement strategies.
authors.affiliation: Department of Medicine, Roswell Park Cancer Institute and the University at Buffalo, Buffalo, NY 14263, USA. marwan.fakih@roswellpark.org
authors.forename: Marwan G
authors.initials: MG
authors.lastname: Fakih
authors.forename: Donald L
authors.initials: DL
authors.lastname: Trump
authors.forename: Candace S
authors.initials: CS
authors.lastname: Johnson
authors.forename: Lili
authors.initials: L
authors.lastname: Tian
authors.forename: Josephia
authors.initials: J
authors.lastname: Muindi
authors.forename: Annette Y
authors.initials: AY
authors.lastname: Sunga
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000150:complications* / Q000188:drug therapy*; D003710:Demography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D014807:Vitamin D / Q000378:metabolism; D014808:Vitamin D Deficiency / Q000209:etiology*
chemical_list: D014807:Vitamin D