Association between serum 25(OH) D and death from prostate cancer

Based on observations that for certain cancers, mortality varies according to sun exposure, vitamin D has been proposed to influence on disease progression. This study aims to investigate whether serum levels of 25( OH) D are associated with prognosis in patients with prostate cancer. In total, 160 patients with a serum sample in the JANUS serum bank were included. For 123 patients a pretreatment serum sample was taken, whereas 37 of the patients had received hormone therapy prior to the blood collection. The serum level of 25( OH) D was classified as low ( < 50 nmol l(-1)), medium (50-80 nmol l(-1)) or high ( 480 nmol l(-1)). A Cox proportional hazard regression model was used to assess the association between serum 25( OH) D and cancer mortality. During follow-up, 61 deaths occurred, of whom 52 died of prostate cancer. The median time of follow-up was 44.0 months ( range, 1.2-154.6). Serum 25( OH) D at medium or high levels were significantly related to better prognosis (RR 0.33; 95% CI 0.14-0.77, RR 0.16; 95% CI 0.05-0.43) compared with the low level. Analysis restricted to patients receiving hormone therapy gave a stronger association. The serum level of 25( OH) D may be involved in disease progression and is a potential marker of prognosis in patients with prostate cancer.