
AI Can Detect Illnesses in Human Breath - jonbaer
https://news.developer.nvidia.com/ai-can-smell-illnesses-in-human-breath/
======
Herodotus38
I read the paper, they had 11 patients with known cancer and trained the NN to
detect volatile organic compounds in the breath from raw GC-MS (gas
chromatography mass spectrometry) data. From what I understand, the
interesting and novel application is in the NN learning to parse the data for
the detection of the aldehydes they were interested in. Nothing about this
paper involves testing in patients where you aren't sure if they have cancer
or not from what I read. Lots of false positives as well. Furthermore, whether
or not this type of breath testing is useful in diagnosis is an open research
question.

In my opinion, from a medicine standpoint this paper is pretty far from being
applicable to patients, and may never be, although that is par for the course
for a lot of medical research. I'm not smart enough to comment on the ML
details.

------
Tycho
I was thinking how things like this could revolutionize healthcare by reducing
the need for doctors, who we never have enough of. But you know the saying, AI
is always the thing we can't do yet? Meaning the goalposts shift, and stuff
that was previously considered a goal of AI research is now just boring
automation, and so AI is still a distant dream. Well it occurs to me that
there is something similar with healthcare: healthcare is whatever is still
expensive to provide. Regardless of how many life-saving treatments and
inventions are adopted, there will still be some things that only
hospital/clinic staff can help you with. And so we will always have the same
bottleneck and people will always complain about access to healthcare, using
this bottleneck as their barometer.

~~~
Waterluvian
The beauty of AI in medical screening is that unlike driving, 90% accurate is
still a valuable tool.

Imagine if your toilet said, "uh hey so your X levels seem unusual. This might
be nothing but you should seek a doctor"

~~~
danenania
The problem here is that due to the base rate fallacy, accuracy percentages
for medical tests are widely misinterpreted, so a "90% accurate" disease-
screening toilet is a recipe for lots of unnecessary procedures and emotional
trauma. Even at 99%, a positive hit for most diseases is still probably a
false positive.

~~~
stickfigure
That seems... ok?

It might even be a good thing. With enough regular feedback, we might
emotionally adjust to the realization that "maybe you should get checked out"
is not _OMG I 'm going to die_.

~~~
lomnakkus
a) It's just not that easy to "everybody needs to adjust" \-- people are
different wrt. what causes anxiety, etc. It seems a priory quite plausbile
that there's a significant genetic component to this.

b) "Get checked" may itself cause problems, for example: Scans for breast
cancer involve radiation which may actually _cause_ cancer. Biopsies can also
be quite invasive. Obviously the risk is low, but depending on the exact
numbers and it might actually be better to _not_ get screened until one is in
a _known_ high-risk group (where the base rate fallacy doesn't skew the
results so much).

~~~
goodpoint
> It's just not that easy to "everybody needs to adjust" Education exists for
> this.

> It seems a priory quite plausbile that there's a significant genetic
> component to this.

 _a priori

There's a very popular trend to imagine genetic components in every human
behavior. It's not just incorrect, it's very dangerous.

> Scans for breast cancer involve radiation which may actually cause cancer.

That's easily handled using common practices. If breath _and* blood test are
positive do CT scan.

~~~
lomnakkus
No. Just... no.

------
googlemike
Sensitivity and specificity scores or go home.

~~~
colordrops
Even if the false positives were high, couldn't it be used as a first pass to
indicate more accurate testing?

~~~
darawk
Sure, but publish the numbers so we can decide for ourselves.

~~~
semi-extrinsic
They have numbers in the paper[0] linked in TFA. They trained on 29 samples
and tested on 12 samples. On those samples, all techniques (NN, SVM, CNN) all
had 100% true positive rates. The CNNs did best on false positives, giving on
average 2-3 per sample.

Also, it is very important to note: they are comparing a CNN analysing a GC-
MS[1] sample to a human expert analysing a GC-MS sample, which is basically a
1D plot of intensities of chemicals. This is not a comparison to a human
smelling someone's breath.

Also, as far as I can see, they never compare to a GC-MS run with selective
ion monitoring (SIM), which would be a lot faster for the human to analyse.

[0] (ResearchGate link, sorry):
[https://www.researchgate.net/publication/324921031_Convoluti...](https://www.researchgate.net/publication/324921031_Convolutional_neural_networks_for_automated_targeted_analysis_of_raw_gas_chromatography-
mass_spectrometry_data)

[1] A gas-chromatograph mass spectrometer is a device which samples a gas and
detects what chemical species are present. It's what they do at airports when
they swipe that piece of fabric on your luggage and put it in a machine (GC-
MS) to look for explosives. It's a nice tool, used extensively in labs
worldwide, but expensive (usually a couple hundred thousand USD, depending on
specifications).

~~~
amacbride
Forty-one total samples? Um...its not _quite_ anecdata, but call me when the N
is a bit larger.

~~~
Cyph0n
Maybe obtaining and analyzing these samples is a more complicated process than
we think? For example, acquiring and analyzing a malware sample is not
equivalent to labeling or classifying an image.

------
benatkin
Does anyone know if TSA gate agents can see tumors, and if they've ever told
anyone? Like, say, a golf-ball sized tumor in the neck? Would they have to be
medically trained? Do they avoid or encourage hiring former radiologists?

There was an interesting story of a doctor who noticed cancer while watching
TV and passed the word on. [https://abcnews.go.com/GMA/Wellness/woman-
appeared-hgtv-find...](https://abcnews.go.com/GMA/Wellness/woman-appeared-
hgtv-finds-cancer-doctor-watching-spots/story?id=55640226)

~~~
tjohns
There's no human operators for the body scanners anymore, due to privacy
concerns. The images are analyzed by computer, and any anomalies are
highlighted on a cartoon diagram for extra attention during the pat down.

Also, if someone had a golf-ball sized growth on the outside of their body,
I'm sure the person is already aware of it. (The body scanners can't see
inside the body.)

------
anjc
>“Computers equipped with this technology only take minutes to autonomously
analyze a breath sample that previously took hours by a human expert”

The AI is impressive, but I'm equally impressed that a human can sniff
someone's breath for a few hours and diagnose cancer. Amazing.

~~~
Covzire
"Didn't my receptionist tell you not to eat and drink only water for 24
hours?"

------
ruytlm
Also relevant: The woman who can smell Parkinson's disease:
[https://www.bbc.com/news/uk-scotland-42252411](https://www.bbc.com/news/uk-
scotland-42252411)

------
doggo_
Odd how the baseline mentioned in the article is better then human average.
Why wouldn't the baseline be dogs, or existing non-breath tests?

~~~
stevenwoo
From what I can tell, dogs worked well in the laboratory, but it did not work
well in the field. In the lab they usually had 1/5 or so positive samples, but
in the field, it was a much lower positive rate depending upon cancer and the
dog handler would not be able to give positive reinforcement immediately in
the field, also different dogs have different success rates.
[https://www.livescience.com/61234-how-dogs-smell-
cancer.html](https://www.livescience.com/61234-how-dogs-smell-cancer.html)

~~~
asafira
very cool! I wonder if they could sprinkle in some fake examples for the dogs
so that they could give positive reinforcement more often.

------
roryisok
“Computers equipped with this technology only take minutes to autonomously
analyze a breath sample that previously took hours by a human expert,”

They make it sound as if the human expert was also sniffing peoples breath,
trying to smell cancer

------
ed312
Is this possibly related to the phenomenon of dogs knowing someone is sick?

~~~
joe24pack
That was my first thought too.

------
thomasfedb
Worth pointing out that humans can also smell disease in human breath - broad
odours point to disease of particular organs (liver, kidney) and also to some
specific diseases (diabetes).

~~~
ambicapter
Is this why old people smell old?

~~~
GolDDranks
I don't think we know 100% how much specific diseases contribute, but there is
at least ongoing research about that, and it seems there is general changes in
body odour composition:
[https://en.wikipedia.org/wiki/Old_person_smell](https://en.wikipedia.org/wiki/Old_person_smell)

------
nl
This should surprise no one.

This 2016 study[1] build a device which could detect 17 diseases via breath,
and I think that was a manually built algorithm.

It's well known that dogs can smell cancer too (there's a 2006 study but I
can't find it now).

[1]
[https://pubs.acs.org/doi/full/10.1021/acsnano.6b04930](https://pubs.acs.org/doi/full/10.1021/acsnano.6b04930)

------
jadeddrag
Are there any estimates about releasing this technology for general use? Or
does the (US) FDA insist on slowing down this type of diagnostic technology a
few decades, or can we expect to see these as kiosks in every clinic over the
next few months?

~~~
rabbitonrails
The new Theranos Blockchain is already manufacturing diagnostic units.

------
randop
This is interesting to see being used in real world. Still wondering what
types of cancer it can detect. Maybe throat cancer, who knows.

~~~
jcims
I read a few anecdotes that said that nurses who were familiar with cancer
patients would subconsciously identify an odor that was associated with them.

Then they would smell it in the wild and be struck with a sudden an anxiety
about whether or not they should tell the person to get checked, given the odd
nature of the clue.

------
vidoc
I misread the title and thought "I" instead of "AI". I was like, I'm clicking
now!

------
Bromskloss
That doesn't sound dramatically different from being able to diagnose things
from a blood sample.

~~~
rabboRubble
It does from the perspective of the blood giver. Many people are dreadfully
afraid of needles to the point their unwillingness to do preventative tests.
Also reduces the knowledge needed to administrate the test and possibly the
eventual cost of executing the test. No phlebotomists needed to exhale.

------
zdmc
"...with better than-human average performance". Hmm. Is this a task that
humans currently do well?

------
weregiraffe
Soon, AI will smell your weakness and go in for the kill...

------
beebmam
I'm getting strong Theranos vibes from this.

~~~
felipemnoa
That was my first thought too. We'll be branded heretics, unfortunately.

~~~
matte_black
Just know you are not alone.

------
nashashmi
I have suffered with severe nasal allergies as a kid. And had a hard time
smelling anything because my nose was stuffed. I realized that I developed a
sense of "smell" in my hand. I could actually feel the air. And tell what it
smells like.

For those who can't believe it, smells have a pH, humidity, heat capacity,
temperature, density, and pressure to them. So if you can train your skin to
be sensitive and concentrate on those things you can feel smells.

It was not long till I realized that people give off a certain odor. And those
odors are often related to the germs on their body. And the food they ate.
Sometimes I could even tell if the person was sick.

I never developed a method of detecting illnesses simply by waving my hand on
the person unless I was acutely familiar with the sickness, but if we can
develop machines to detect "smell" (a fact I did not know) then we can
definitely detect machines to scan people as they walk through a door and tell
what germs they carry.

Of course my dream powers are to tell what antigerm ointment each person
should use.

