Dogs Trained To Sniff Out Ovarian Cancer

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."

Comments

Wanted: Annoying crotch sniffing dog

[Anonymous Coward]

Wanted: Annoying crotch sniffing dog. While any breed will do, one who's head is about waist height and who's nose is not too messy is preferred. Top dollar will be paid for obsessive-compulsive sniffers.

Re:Wanted: Annoying crotch sniffing dog

[glueball]

Dog will work in the lab. After positive patient finding, send patient to cat scan.

Re:Wanted: Annoying crotch sniffing dog

[FuegoFuerte]

Mr. Anonymous, sorry about your loss - such things are never easy.

I hope you're not overly offended by those of us who make light of the image of crotch-sniffing dogs in women's clinics. I'm not sure of the person who made the "Wanted:" comment above, but for many people (myself included) humor is simply a way of dealing with the unpleasant and often painful realities of life. So, it's not an attempt to be dismissive of the pain and overall nastiness of the disease, but more coping mechanism. At least for some. Others truly are just insensitive clods.

Bad metric

[Grantbridge]

"When it's caught early, women have a five-year survival rate of 90 percent" - this is true for nearly all cancers even if there is no treatment. The fire-year survival rate depends MOSTLY on when you diagnose someone. And if you have a high false-positive in your diagnosis then you get a really big boost to the five-year survival rate. Screening programs boost the metric, but they don't necessarily boost actual survival, as the fire-year time starts from diagnosis.

Re:Bad metric

[JustOK]

It usually takes a lifetime to kill you.

Re:Bad metric

[K. S. Kyosuke]

And if you have a high false-positive in your diagnosis then you get a really big boost to the five-year survival rate.

Hmm, are you sure that this is relevant? I would have thought that after getting a positive on a screening test, what you eventually do (perhaps after using one or more other screening methods) is a biopsy. As in, putting the stuff under the microscope being the reference diagnostic method for neoplastic tissue changes and all that jazz. I'd assume that when giving the five-year survival rate, you only consider patients with definitive diagnoses with false positives having been already excluded.

Re:Bad metric

[Sockatume]

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

[Grantbridge]

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.

Re:Bad metric

[blackest_k]

10-year relative survival ranges from 84.1% in stage IA to 10.4% in stage IIIC
  Survival rates based on SEER incidence and NCHS mortality statistics, as cited by the National Cancer Institute in SEER Stat Fact Sheets â" Cancer of the Ovary http://seer.cancer.gov/statfacts/html/ovary.html

In Laymans terms if Ovarian Cancer is caught early then treatment such as Surgery and Chemotherapy have a reasonable chance of keeping women alive for 10 years or more, diagnose later and the chances are she will die. Screening really is about the only method of catching treatable cancers at an early enough stage that they can be treated since if you don't look for it , it tends to be already at an untreatable stage when it is eventually discovered.
Obviously screening doesnt make the untreatable , treatable but it does save lives where early treatment can make a difference. It's not pointless which is what you appear to imply.

Re:Bad metric

[Dcnjoe60]

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:Bad metric

[FuzzNugget]

You haven't heard of acute cancers? The untreated survival rate there is 0% after about a month or two.

Re:Bad metric

[danceswithtrees]

I think that early detection always saves at least some lives.

Another important consideration is at what cost? For example, you get a positive screening test. To get final detection, you need to undergo an invasive biopsy (such as a needle inserted into your anus for a prostate biopsy). If the biopsy shows cancer, you might get surgery to get it taken out. Surgical complications, including death. Hospital acquired infections, blood clots, etc. For prostate surgery, a significant risk of incontinence and impotence. So take 100 men with prostate cancer, couple have significant bleeds during biopsy, a couple die during surgery (these are usually older men with other health problems), a few pneumonias, a third leak urine, half have problems getting it up any more. Perhaps the surgery is only 30% effective at eradicating cancer even at the earlier stage. You have now actively killed a few people to save some in the future. Some you put through invasive procedures and surgery without improving their overall prognosis. Given that lead-time bias, these improvements can be very difficult to find-- you can no longer use historical controls because historical controls were not diagnosed the same way-- you therefore need to use a randomized trial.

The math may or may not work out depending on how good the screening tests are, how invasive the confirmatory tests are, how dangerous the surgery is, how EFFECTIVE is the surgery at preventing cancer related deaths, etc. These are the issues that doctors (and those who set public health policy) agonize over. That is why screening recommendations evolve over time.

Genitals

[Olix]

This is a pretty good idea as dogs like to smell genitals anyway. They should do it for testicular cancer too.

Re:Genitals

[Anonymous Coward]

They'll probably bite them off. But if you would rather have them lick it, you could use peanut butter.

Slow news day for agencies

[Anonymous Coward]

2012
http://www.cbsnews.com/8301-204_162-57553262/doctor-dogs-being-trained-to-sniff-out-ovarian-cancer/

2009 (Can Dogs Sniff Out Cancer?)
http://www.cbsnews.com/8301-18560_162-703845.html

2006 (Dogs Excel In Cancer-Sniff Study)
http://www.cbsnews.com/2100-500368_162-1204680.html

every few years it pops up, but still nothing other than studies, perhaps its just a funding thing

In some cases

[SpaghettiPattern]

In some cases I'd try and give the dog a run for its money.

When asked for comment

[OzPeter]

A selection of cats said "Meh".

Re:Generic symptoms?

[Sockatume]

There are no "generic symptoms on a healthy person" because by definition a symptom is an abnormality associated with disease. Generic symptoms are merely those that are associated with many possible underlying conditions. Headaches, fatigue, and fever, for example, aren't particularly diagnostically useful.

Re:Generic symptoms?

[jbengt]

From the summary: " But because of its generic symptoms — weight gain, bloating or constipation". Those aren't generic symptoms on a healthy person.

I don't think you understand what generic means, at least not in this context.
Those are very generic symptoms, and healthy people, by definition, don't have symptoms.

One big problem

[smooth wombat]

But because of its generic symptoms â" weight gain, bloating or constipation â" the disease is more often caught late."

How are we supposed to tell the difference between the symptoms of ovarian cancer and the general appearance of large portions of the female population in the U.S.?

I think my dog's already trained for this...

[hyades1]

...based on where he tries to stick his nose every time a woman between 12 and 80 comes into the room.

Re:Generic symptoms?

[Aonghus142000]

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.