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A Blood Test That Screens For Cancer
sciencehabit writes "People usually find out that they have cancer after developing symptoms or through a screening test such as a mammogram—signs that may appear only after the cancer has grown or spread so much that it can't be cured. But what if you could find out from a simple, highly accurate blood test that you had an incipient tumor? By sequencing the abnormal DNA that a tumor releases into a person's bloodstream, researchers are now one step closer to a universal cancer test. Although the technique is now only sensitive enough to detect advanced cancers, that may be a matter of money: As sequencing costs decrease, the developers of the method say the test could eventually pick up early tumors as well."
If it works with early forms of cancer, this is nobel prize material.
So the logical question is... just how much money is required to change this sentence "This is an exploding field." He thinks such tests could reach the clinic within 5 to 10 years. " to read ".... within 1 to 2 years"?
The reason it's so hard to treat and there are so many treatments is that each and every cancer has it's own unique fingerprint in terms of how it works, what it responds to.
It would be nice but I can't see any one test being able to identify all possibilities any time soon. As the article says, it's a step.
I want a list of atrocities done in your name - Recoil
http://xkcd.com/1141/
Moore's law is not a law. Theory, yes; Predictable trend, certainly; Law, no.
The problem with this is its still just a preventative measure. While its great if they can accomplish this as it will save many live, it does not stop the fact that they might still get more recurring cancer. Coming from a friend of an Hematologist oncologist (blood cancer doctor), he stated to me once that the doctors aren't so much trying to prevent cancer but more of trying to treat it. And even so they are very much in the dark because cancer is a mutated cell linked to the host its in. So as you go from person to person its different every time. The link should be what prevents cancer, but until they change their way of thinking most doctors are chasing dog tails.
I hope they develop better ways of locating the cancer in the body as well, otherwise it will be just like it is now. Dear Sir/Madam your tumor marker has shot up 10x, but we can't find where it's spread, so sorry.
Most interesting cancer treatment research to me:
- Dichloroacetic acid (it's as close to free as possible and has known side effects and is available some places now) but seems to work best in combination with chemo
- anti-CD47 (has the potential to treat numerous cancers, but it's early)
If the test is too sensitive, then it will likely find that everybody has multiple cancers right from -8 months.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Some screening tests for cancer byproducts already exist, like the PSA test for prostate cancer. Other early-detection tests abound, such as Mammograms and Colonoscopies. While some of the screening tests, such as the Pap Smear, have shown to dramatically reduce cancer deaths, others, such as the PSA and Mammogram have detected a lot of cancers, but done absolutely bupkis to reduce death rates when given to populations not otherwise at high risk. Colonoscopies work, but are extremely expensive vs. the benefit they provide. (As in, it'd be a lot more efficient to spend healthcare dollars elsewhere, and there are other screening tests nearly as effective that are much cheaper.) Apparently they don't do a good job detecting aggressive cancers in those populations early enough to make a difference. With how fast some aggressive cancers work, the tests might have to be administered several times a year (at the cost of countless billions) to make any difference.
In addition, the PSA and Mammogram HAVE caused billions to be spent on procedures with quite severe side effects to further diagnose, and treat, problems that almost certainly would not have killed their "victims." Most Prostate tumors grow slowly enough that you could leave it alone for the rest of your life, and die of something else instead; meanwhile, prostate cancer treatment almost always causes problems with incontinence and impotence; two major quality of life issues. Most "breast cancers" detected by mammograms are Ductal Carcinoma In Situ, another type of cancer that is unlikely to kill you any time soon.
We need to think VERY carefully before rolling out any MORE widespread cancer screening tests, since many of the ones we have now simply don't work.
Your headline is more true than you realize... although you don't realize it.
Something like 2/3rds of the population that we would consider to die of "old age" (generally defined as dying of a condition that predominately kills the elderly, and doing so at around, or greater, than the average lifespan for a developed country), have been discovered, upon death, to have cancer of some sort, but cancer that did NOT contribute to their death. IIRC, the most "popular" are Prostate, Breast, and Brain tumors. Some of those tumors may have been decades old, but slow-growing and non-aggressive enough to simply not be an issue.
Not all cancer is worth detecting if it's almost inevitable that you'll die from simply "wearing out" first.
Medical screening is a tricky subject - see the wikipedia article for a better overview of it all. However tests aren't 100% foolproof, and if you look up terms such as sensitivity, specificity, positive predictive value, false positive etc. on wikipedia it will give you a general indication of how these tests really work. I do not believe that you can have a test that screens for all cancer that is useful. Or if I put it this way when will it pick up cancer? Can it pick up ALL cancers early enough that you can do something about it? Will there then be false positives (worrying patients, giving them unnecessary treatment with the associated side effects), or false negatives (i.e. people not picked up)? Or are they making a test that picks up all cancers when they have metastasised (i.e. spread to the other parts of the body) when people cannot be treated? The last example is not the useful one. It is useful to see the principles of screening on the first section of the wikipedia article. It will give people a general background on tests and why they may or may not pick up things. Medicine (and the human body) is somewhat of an inexact science so some cancers may not be picked up until they are untreatable, and patients may not understand why they personally have fallen through the net. The article seems to acknowledge that this is still a research idea - the important bits are that they screened 'advanced' cancers, some of the statistics, and the cost. I do support researchers as I know that advances can take a long time to prove and filter through from research into something that is useful.
When it's in your blood, it's already in metastasis and it's too late.
No one is "winning" the battle against cancer in general.
The cancer rate is increasing, not decreasing, despite all of the money spent and gone over the past 50 years.
Were killing ourselves by consumption and exposure to unnatural and unnecessary chemicals produced by a highly profitable chemical cartel.
Look, even the mammogram industry (doctors, hospitals and manufacturers) has programed the public with the myth that mammograms saves lives.
After ten years of study, it's been shown to not be true.
More people are diagnosed, but no more people die.
Mammograms are painful and a waste of time and money in many cases, but the almighty dollar is mightier than the truth.
And breast cancer rates keep going up, no matter how many ribbons people wear and money they give.
its like trying to do a Spam Filter
if you get X "hits" it might be spam/cancer if you get Y hits you do more traditional tests if you get Z hits its time to book the MRI for a Scan.
So Over reporting is not a problem its UNDER reporting they need to watch out for.
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Regular CBCs will detect many irregularities, but not all. Most people don't do CBC checks regularly, even though they are fast and easy.
Good thing for the PPACA or this can be a ticket to being blacked list for life in the USA.
People seem to be concentrating on the false-positive rate that this would cause, the more sensitive it gets, due to the bodies regular development of cancerous cells; but this instead has the potential to be a true goldmine of information, in using statistical studies to far more accurately determine what can increase your rate of cancer.
If you had a hyper-sensitive blood test, and you regularly measure the incidence of cancerous cells in the body, you can use that to make all sorts of highly accurate correlations as to what causes cancer, by matching up higher or lower than average instances of cancerous cells, to exposure to certain chemicals/drinks/foods etc..
I was diagnosed with Barrett's Oesophagus a short while ago, and told the only method to monitor it's progression was with annual endoscopic surveillance. I did some research and found a paper that linked the percentage of Eosinophil cells (a subclass of white blood cell) with the stage of the condition, with statistical significance. And when the story of the pregnancy stick and the testicular cancer circulated a few weeks ago, a little more research revealed a similar study linking levels of hCG to the development of Adenocarcinoma (with the suspected link being an increase in vascularity), again with statistical significance.
So, now instead of waiting for an annual biopsy to tell me that it's too late (there's a 15% five year survival rate once detected), I can do a simple blood test (CBC with Diff) and pee on a stick once a month to monitor my own condition, and if things begin to change before the annual surveillance I can go to my GP/Specialist and present the evidence and ask them to investigate further.
No expensive procedures, no patents (see: breast cancer testing), no fuss, no muss
They detect my bladder cancer (or temporary lack thereof after a resection) by FISH (http://en.wikipedia.org/wiki/Fluorescence_in_situ_hybridization) performed on selected cells from a urine specimen. It shouldn't be much different doing it on cells from a blood sample...