Vitamin D deficiency is associated with increased risk of prostate cancer for those with elevated prostatespecific antigen (PSA) level or abnormal digital rectal examination. Vitamin D deficiency is also associated with aggressive prostate cancer. Vitamin D level could be added as an additional factor to consider before ordering a biopsy. Clin Cancer Res; 20(9); 2241-3. Ó2014 AACR. This study offers further evidence that vitamin D deficiency is a risk factor for aggressive prostate cancer. Gilbert and colleagues associated low 25(OH)D levels with a 2-fold increased risk of advanced versus localized prostate cancer or high-grade versus low-grade prostate cancer (2). As with most observational studies (2), this study also found no correlation of serum 25(OH)D level with overall prostate cancer risk.
In this issue ofThese findings have important benefits in helping men decide what to do after learning they have an elevated PSA level or an abnormal digital rectal examination. The authors note, "Most men who are diagnosed with localized prostate cancer attempt curative therapy with surgery or radiation, although observation may be appropriate for men with lowrisk cancers or limited life expectancy" (3). Biopsies are associated with inconveniences as well as risk factors such as bloodstream infections (4).For nonaggressive prostate cancer, watchful waiting or active surveillance is often a better option than invasive treatment, which can affect sexual function, urinary function, and fertility, and can slightly increase risk of colorectal cancer (5). The UK National Institute for Health and Care Excellence recently issued new guidelines for active surveillance, which involve a 5-year program of PSA testing followed by MRI if the PSA changes irregularly during this time (5). A recent study evaluated tools being developed and used to select and monitor patients on active surveillance for low-risk prostate cancer (6): MRI, serum markers, urinary markers, histopathology markers, and germline genetic markers. All have pros and cons, and no indications of long-term outcomes are yet apparent. Serum 25(OH)D levels seem to be another tool for this purpose.These tools offer further evidence that vitamin D deficiency helps explain the black-white prostate cancer disparities. All-cause mortality rates for men with prostate cancer are 25% to 40% lower for those with low compared with those with high serum 25(OH)D levels, whereas prostate cancer-specific mortality rates are about 10% to 20% higher for AA men than white American men (WA) after consideration of socioeconomic status, stage at diagnosis, and treatment (7). In addition, a vitamin D 3 supplementation study of patients on active surveillance with early-stage, low-risk prostate cancer found that among men given 4,000 IU/d of vitamin D 3 , half had fewer positive cores at repeat biopsy 1 year after enrollment in the study (8). The authors suggest that such vitamin D 3 supplementation could reduce prostate cancer-related health disparities in AA men. However, based on evidenc...