So Vitamin D seems to be a big hot topic right now with respect to cancer. here is a thread with a study about how it can positively prevent non skin cancers in older women:

Of course Vitamin D would have positive benefits on men, but what about in preventing similar cancers?

The study stated that cancerous cells had high levels of IGF-1 and IGF binding protien 3 expression....any correlation between that and an increasing risk of cancer in men who supplement with IGF-1??