title: The association between pre-treatment serum 25-hydroxyvitamin D and survival in newly diagnosed stage IV prostate cancer.
abstract: OBJECTIVE
  Emerging evidence in the literature suggests a positive association between serum 25-hydroxyvitamin D [25(OH)D], a standard indicator of vitamin D status, and survival in certain types of cancer. We investigated this relationship in newly diagnosed stage IV prostate cancer patients.
  
  
  METHODS
  A consecutive cohort of 125 newly diagnosed stage IV prostate cancer patients underwent a baseline serum 25(OH)D evaluation prior to receiving any treatment at our institution between January 2008 and December 2011. We used the vitamin D categories of "deficient (<20 ng/ml)", "insufficient (20 to 32 ng/ml)", and "sufficient (>32 ng/ml)". Cox regression was used to evaluate the prognostic significance of serum 25(OH)D after adjusting for relevant confounders.
  
  
  RESULTS
  Mean age at diagnosis was 60 years. Of the 125 patients, 32 (25.6%) were deficient, 49 (39.2%) were insufficient and 44 (35.2%) were sufficient in vitamin D at the time of diagnosis. The median survival in deficient, insufficient and sufficient cohorts was 47.8, 44.0 and 52.6 months respectively (p = 0.60). On univariate analysis, four variables demonstrated a statistically significant association with survival: nutritional status, bone metastasis, corrected serum calcium and serum albumin (p<0.05 for all). On multivariate analysis, five variables demonstrated statistically significant associations with survival: hospital location, age, bone metastasis, serum albumin and corrected serum calcium (p<0.05 for all). Serum vitamin D status was not significant on either univariate or multivariate analysis.
  
  
  CONCLUSIONS
  Contrary to previously published research, we found no significant association between pre-treatment serum 25(OH)D and survival in newly diagnosed stage IV prostate cancer patients. The lack of a significant association between serum vitamin D and survival in our study could perhaps be due to the fact that the disease was far too advanced in our patients for vitamin D levels to have any impact on prognosis.
authors.affiliation: Cancer Treatment Centers of America (CTCA) at Midwestern Regional Medical Center, Zion, Illinois, United States of America.
authors.forename: Digant
authors.initials: D
authors.lastname: Gupta
authors.affiliation: Cancer Treatment Centers of America (CTCA) at Midwestern Regional Medical Center, Zion, Illinois, United States of America.
authors.forename: Kristen
authors.initials: K
authors.lastname: Trukova
authors.affiliation: Cancer Treatment Centers of America (CTCA) at Midwestern Regional Medical Center, Zion, Illinois, United States of America.
authors.forename: Brenten
authors.initials: B
authors.lastname: Popiel
authors.affiliation: Cancer Treatment Centers of America (CTCA) at Midwestern Regional Medical Center, Zion, Illinois, United States of America.
authors.forename: Carolyn
authors.initials: C
authors.lastname: Lammersfeld
authors.affiliation: Cancer Treatment Centers of America (CTCA) at Midwestern Regional Medical Center, Zion, Illinois, United States of America.
authors.forename: Pankaj G
authors.initials: PG
authors.lastname: Vashi
mesh_terms: D018572:Disease-Free Survival; D006801:Humans; D008297:Male; D009367:Neoplasm Staging; D011471:Prostatic Neoplasms / Q000097:blood* / Q000401:mortality* / Q000473:pathology; D015996:Survival Rate; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D