Dogs Trained To Sniff Out Ovarian Cancer 83
Hugh Pickens DOT Com writes "Dogs have been trained to sniff out drugs, explosives, cadavers, mobile phones, firearms, and money but now AP reports that researchers have started training canines to sniff out the signature compound that indicates the presence of ovarian cancer. If the animals can isolate the chemical marker, scientists at the nearby Monell Chemical Senses Center will work to create an electronic sensor to identify the same odorant. "Because if the dogs can do it, then the question is, Can our analytical instrumentation do it? We think we can," says organic chemist George Preti. More than 20,000 Americans are diagnosed with ovarian cancer each year. When it's caught early, women have a five-year survival rate of 90 percent. But because of its generic symptoms — weight gain, bloating or constipation — the disease is more often caught late."
Re:Bad metric (Score:5, Informative)
After a bit of Googling, it looks like this is called the "lead time bias" and is a rather significant issue with interpreting the benefits of a diagnostic test. That said, when 70% of sufferers aren't discovered until after metastasis, a better diagnostic method is desperately needed.
Re:Bad metric (Score:5, Informative)
Re:Bad metric (Score:5, Informative)
Well it depends on the cancer, I don't know about for Ovarian in particular, but for prostate you often find cancerous tissue, but it is so slow growing it wouldn't be a threat unless you lived to be over 100, and as such the side effects of treatment are much worse than the cancer would have been. These sorts of slow growing non-threatening cancers wouldn't ever produce symptoms, and so wouldn't be diagnosed without a screening programme.
That is true with prostate cancer, but not ovarian cancer. Besides in relation to the original post, finding cancer cells in one's prostate, even if slow growing would not be a false positive but an actual positive. But yes, if you are 80 and they find prostate cancer they may not do anything about it. If you are 60 and they find it, they aren't going to just let it go.
Re:Generic symptoms? (Score:2, Informative)
This is something I can speak to directly. My wife was diagnosed with stage 3 ovarian cancer 1 year ago this month. She is gone to intravenous chemo, surgery, and she is now on a yearlong oral chemo.
When she was diagnosed, what symptoms she had had shown up less than two weeks before. At the time, they consisted of cramping, constipation, and irritability. In other words, exactly the same symptoms she had exhibited once a month since puberty. By the time they found it, she had an 11 cm mass that had begun to metastasis into the abdominal wall. The symptoms themselves were actually caused by the 5 liters of fluid that had built up in her abdominal cavity.
As she is not of Eastern European Jewish descent and has no family history of cancer, there was absolutely no reason to suspect what was going on. Herein lies the problem with detection of this type of cancer, it just does not show any signs until it is well along. While I applaud the work in training canines to detect it, there is already a fairly accurate blood test to find ovarian cancer. For the canine route to be effective, pretty much every woman would have to be subjected to a crotch sniff from one of these canines.