Snopes and TruthorFiction.com

Snopes, Hoax Slayer, Skeptics Annotated Bible.

The year 2002 did indeed happen.

Many service dogs are indeed able to detect bladder and ovarian cancer, predict an epileptic seizure and detect subtle changes in the body of a diabetic.

Here

For medical sources I usually go to science based medicine
http://www.sciencebasedmedicine.org/what-to-make-of-medical-dogs/

Another good place is Skeptoid.com

@Rarebear : I stand, sadly, corrected. I loved the stories of the service dogs and am sad to learn it is not true.

I am with @gailcalled those stories are awesome and if we use canine units to detect drugs why not… Sometimes it doesn’t pay to be a skeptic so while evidence may be largely anecdotal (I say may because this isn’t a topic I’m strong on) and clinical trials may be in early stages I think it is too early to give up on this one. http://www.sciencedaily.com/releases/2006/01/060106002944.htm

Later http://scienceblog.cancerresearchuk.org/2009/02/03/can-dogs-detect-the-smell-of-cancer/

Current http://m.cbsnews.com/storysynopsis.rbml?&pageType=health&url=http%3A%2F%2Fwww.cbsnews.com%2F8301-204_162-57597863%2Funiversity-of-pennsylvania-training-dogs-to-sniff-out-ovarian-cancer%2F&catid=57597863&nb_splitPage=5

http://www.straightdope.com/ is pretty good too.

Thanks everyone.
By the way, I just heard that they need the cancer…..(I can’t think if the terminology) in the breath or the blood (not before) in order for different kinds of cancer, to be detected.