A few members of my family have had cancer, including prostate cancer. Because of this I always try to run the 10km run by my local cancer hospice because they do a great job. I also do the Cancer Research 10km in my local park.

There is also a men only race in Glasgow, the point of which is to raise awareness of prostate cancer in men (which I'm taking part in too).

There's a chance that there might be a local race near you in aid of a local cancer charity (such as a local hospice) that you could enter - that way you could still enter a race to beneift a charity.