Vitamin D is involved in a number of vital processes in the body, and the association between low Vit. D levels and various cancers, including prostate cancer, has been extensively studied. The first results came from epidemiologic studies known as geographic correlation studies, studies of sunlight exposure(related to Vit. D) and cancer incidence, and individual studies provide evidence that Vitamin D levels tend to be lower in patients with prostate cancer than age matched controls. However, meta-analysis of published literature of studies on vitamin D levels and association with prostate cancer reported no association or little evidence to support a major role of vitamin D in preventing prostate cancer or its progression. Several studies of supplementation of diets of patients with cancer are listed on clinicaltrials.gov, but hard data to recommend testing for Vit D, or supplementation with Vit.D is lacking and there are no guidelines that currently recommend doing so.
Subhashini Yaturu, Sonya Zdunek, and Barbara Youngberg Vitamin D Levels in Subjects with Prostate Cancer Compared to Age-Matched ControlsProstate CancerVolume 2012 (2012), Article ID 524206, 4 pagesdoi:10.1155/2012/524206
Gandini, M. Boniol, J. Haukka et al., “Meta-analysis of observational studies of serum 25-hydroxyvitamin D levels and colorectal, breast and prostate cancer and colorectal adenoma,” International Journal of Cancer, vol. 128, no. 6, pp. 1414–1424, 2011.
L. Yin, E. Raum, U. Haug, V. Arndt, and H. Brenner, “Meta-analysis of longitudinal studies: serum vitamin D and prostate cancer risk,” Cancer Epidemiology, vol. 33, no. 6, pp. 435–445, 2009.
R. Gilbert, R. M. Martin, R. Beynon et al., “Associations of circulating and dietary vitamin D with prostate cancer risk: a systematic review and dose-response meta-analysis,” Cancer Causes and Control, vol. 22, no. 3, pp. 319–340, 2011.
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