Cumulative Radiation Risk -- Don't tell me I'm crying wolf

[CLTann]

I have been sounding alarm at the medical practitioners total disregard on the danger of radiation. Just a little over a week ago, I wrote about this subject but received very feed back. The attached article clearly shows the excessive danger from the current casual attitude by doctors who order another CT scan. Please see below:

CT Scan Radiation May Cause Cancer Decades Later, Study Finds
2009-12-14 21:00:00.3 GMT


By Nicole Ostrow
Dec. 14 (Bloomberg) -- Radiation from computerized tomography scans may cause cancer decades later, according to a study that estimated about 29,000 future malignancies would occur in the U.S. because of CT scans done in 2007.
Most of the cancers are predicted to strike women, who receive more CT scans than men, and about one-third of the projected malignancies may occur from scans performed in people ages 35 to 54, said research published today in the Archives of Internal Medicine. The cancer forecast was based on an estimate that about 72 million CT scans were done in 2007.
The number of CT tests in the U.S. has risen three-fold since 1993, according to the study. More research is required to determine the lowest dose of radiation needed for clear pictures from CT scans to help reduce radiation exposure, said lead study author Amy Berrington de Gonzalez.
"We know that there are great medical benefits to CT scans, but they also involve small risks of cancer because of radiation exposure," said Berrington de Gonzalez, a researcher at the National Cancer Institute in Bethesda, Maryland, in a Dec. 11 telephone interview. "For an individual, the risks are small. So if the scan is clinically justified, then the benefits should outweigh the risks."
CT scans produce detailed images of the body that provide more details than a traditional X-ray. CT scanners are made by Fairfield, Connecticut-based General Electric Co., Toshiba Corp.
based in Tokyo, Munich-based Siemens AG and Royal Philips Electronics NV based in Amsterdam.

Medicare Data

Researchers in the study looked at data from Medicare, the U.S. government health program for those older than 65 or disabled, plus a survey and an insurance database with information on the types of CT scans and the age and gender of patients taking the tests.
Berrington de Gonzalez said the overall risk for any individual is small and depends on the type of scan given and a person's age. A 70-year-old who has a CT scan of the head would have a 1 in 10,000 chance of developing cancer from the test, while a baby who had a chest CT scan would have a 1 in 200 chance, she said.
The researchers found that about 30 percent of scans in the study were performed in adults ages 35 to 54, 13 percent in those 18 to 34 and 7 percent in children younger than 18.

Lung Cancer

The authors predicted that lung cancer will be the most common radiation-related cancer followed by colon cancer and leukemia. Of the 29,000 people who may get cancer from CT scans done in 2007, about 50 percent will die, the researchers estimated. If CT scan use remains at its current level or higher, eventually 29,000 cancers every year could be related to past CT scan use. That number is equal to about 2 percent of the
1.4 million cancers diagnosed each year in the U.S., they said.
A second study in the journal found that radiation doses from CT scans vary greatly and are higher than previously thought. The researchers reviewed CT procedures performed on
1,119 patients in the San Francisco Bay area over five months.
They found a 13-fold variation between the highest and lowest radiation dose for each type of CT procedure. Patients'
exposure to radiation needs to be reduced by standardizing and limiting the radiation associated with each scan, they said. The number of CT scans should be reduced, they said, citing previous reports that 30 percent or more may be unnecessary.
The U.S. Food and Drug Administration issued interim regulations Dec. 7 requiring closer monitoring of CT scans after more than 250 cases of exposure to excess radiation were reported since October.

CT Heart Scans

The researchers, led by Rebecca Smith-Bindman at the University of California, San Francisco, also estimated cancer risk. They project that 1 in 270 women who undergo a CT scan of the heart's blood vessels at age 40 will develop cancer from the procedure compared with 1 in 600 men.
In certain groups of patients for certain kinds of scans, the risk is as high as 1 in 80, said Smith-Bindman, a professor of radiology at UC San Francisco, in a statement. The risk of developing cancer declined "substantially" with advancing age, the authors said.
"It is imperative, particularly given these results, that we start collecting radiation dose data at the individual patient level," Smith-Bindman said in a statement. "Our results point toward the need to start collecting data on what actually happens in clinical practice and then to establish the appropriate standards."

Saving Lives

Donald Frush, chairman of the American College of Radiology's Pediatric Imaging Commission and chief of the division of pediatric radiology at Duke Medical Center in Durham, North Carolina, said detailing the risks is important though CT scans save lives.
"There's a risk with anything we do, whether it's taking antibiotics or crossing the street," he said in a Dec. 11 telephone interview. "We can't lose what the benefits of CT scanning are. The benefits are that CT scans save tens of thousands of lives each year in the U.S. and really helps the medical community diagnose things. CT is one of the most invaluable medical advancements in the last 100 years."
Rita Redberg, editor of the Archives of Internal Medicine and director of Women's Cardiovascular Services at the University of California, San Francisco, Medical Center, wrote in an accompanying editorial that the "explosion" of CT scans in the past 10 years has outpaced proof of their benefit.
"Although there are clear instances when CT scans help determine the treatment course for patients, more and more often patients go directly from the emergency department to the CT scanner even before they are seen by a physician or brought to their hospital room," Redberg wrote.

For Related News and Information:
Health stories from the U.S.: TNI US HEA BN <GO> Top stories about science: TNI SCIENCE WWTOP <GO> Today's most popular health-care stories: MNI HEA <GO> Bloomberg Drug Database: BDRG <GO> Top health stories: HTOP <GO> News about medical research: NI MEDICAL <GO>

--Editors: Donna Alvarado, Andrew Pollack

[Joe]

Ann,
Christine has always been concerned about excessive radiation. She prefers echocardiagrams over MUGA scans.

Regards
Joe

[StephN]

Thanks, Ann -
This is the part that yanked my chain:

"They found a 13-fold variation between the highest and lowest radiation dose for each type of CT procedure. Patients' exposure to radiation needs to be reduced by standardizing and limiting the radiation associated with each scan, "

I had no idea that the dose of radiation for any given test was NOT standardized! Most of my scans have been within one major medical group so I hope they ARE standard and not to the high side ...

Jeez.

[AlaskaAngel]

Past post about rads risk:

http://www.her2support.org/vbulletin/showthread.php?t=28989&highlight=radiation+exposure

There also was a pretty good article on Oncolink a while back discussing this topic that I am trying to re-locate.

Here is another:

http://www.oncolink.org/resources/article.cfm?c=3&s=8&ss=23&id=14806&month=11&year=2007

[Jackie07]

This is scary. I've had a record 4 CTs this year all in the same area (pelvic/abdominal) Doctors must have ordered them because they are cheap. Not sure I will live more than a decade to be harmed by the effect... :) (Wondered if that's the rationale of our doctors? Or they have simply not received the data...)

I did wonder about it when I got breast cancer. But the doctor told me it would not have had anything to do with my Gamma-knife radiosurgery just two years before (very close to the time when my breast cancer had started growing - as was estimated by my my b.c.surgeon.) "People who have one type of cancer tend to get another type of cancer," the neurosurgeon said.

Besides 'it's all in the genes' theroy, I am glad attentions are being made in this regard.

Does the Siemens brand uses a below-average radiation? I'd like to find out...

[Mary Anne in TX]

I have a new cardiologist since being tossed from the trial for Naratinib (ok) and he's doing an ultra sound stress test instead of the regular thing just because of this. My onc will do CTs if I press, but is very aware of the dangers.
But, I think while I was in active treatment, I never gave it a real thought....I just wanted to know whatever! ugh!
Please keep info coming.... ma

[Lien]

Good article. I wonder how much mammo's affect the outcome. We don't just get the CT scans, we get radiation from other sources as well. Would they cause an incremental effect? So much not known. I like to err on the safe side. So I have gradually postponed my 6 monthly and annual mammo's by a month every time, so I will reduce the lifetime exposure and not harm my checkup schedule too much. Over 10 years, I will receive fewer mammo's than I normally would have. And I don't think 1 month makes a lot of difference.

Jacqueline

[Lien]

Oh, and I haven't discussed this with my docs. I just made the appointments one month later. So if you think about stretching the time between mammo's, make sure this is safe for you. My tumor was tiny and there was no node involvement, so I think it should be okay for me. But that's just me!

Love

Jacqueline

[Cannon]

Actually, I had a lot of x-rays as a child/teen (which failed to diagnose my Crohn's) - and I wonder if that didn't contribute to my breast cancer.

When I had to have my gallbladder removed in an emergency procedure last year, I wanted to decline the traditional chest x-ray when you are admitted to the hospital. The resident told me, when you are asleep, we are going to be xraying the heck out of the gall bladder area to make sure we've got it - this is not going to make a difference.

It's a tough call. Who the heck knows?

[hutchibk]

I have typically monitored with PET/CT and brain MRI the last few years. I believe the CT with my PET is a very low dose CT, but now I know to ask for certain. This is good info...

[AlaskaAngel]

Again, in this sophisticated medical world, why are providers thus far incapable of managing to create the same kind of badge for patients that they use with members of the staff to keep a cumulative running dose actually received by each individual, so that there is some reality to what is known and what is not about radiation exposure and its hazards?

Maybe if patients were to ask that question every time they get near a radiology employee, over and over, somebody might get it together for us?

A.A.

[StephN]

Since most of the lower stage cancer patients get few if any scans, it is the metastatic setting where we have the most exposure. Can't tell you how many I have had!
Perhaps because in the past we did not live so long this was not a concern!
The medical community expects us to die of something before another cancer ever catches up with us.

Now that we have some better drugs and have this long monitoring time, it IS more of a concern. We have so few good ways to measure whether a treatment regimen is working, that these scans are what is relied upon.

I will certainly be asking about the new machines at my cancer center and if they are the CTs with the lower doses. Maybe I should just email my onc's nurse with the question.

[Jackie07]

Found this study while trying to locate the citation of the article on the first post:


Cancer Risks and Radiation Exposure From Computed Tomographic Scans
How Can We Be Sure That the Benefits Outweigh the Risks?
Rita F. Redberg, MD, MSc

Arch Intern Med. 2009;169(22):2049-2050.

The introduction of the computed tomographic (CT) scanner ushered in a new era of internal medicine diagnosis. Conditions that once required laparoscopy for diagnosis could now be diagnosed on the radiology reading board. The previously opaque anatomy of the living brain could now be visualized. The best part was that the test was "noninvasive," fast, and painless. With the exception of patients who were allergic to dye or had renal insufficiency, CT was considered completely safe. No wonder it had such a significant effect on the practice of medicine.

Two articles in this issue of the Archives make us question if we have gotten carried away in our enthusiasm. Every day, more than 19 500 CT scans are performed in the United States, subjecting each patient to the equivalent of 30 to 442 chest radiographs per scan. Whether these scans will lead to demonstrable benefits through improvements in longevity or quality of life is hotly debated. What is becoming clear, however, is that the large doses of radiation from such scans will translate, statistically, into additional cancers. With CT scan use increasing annually, it is imperative that clinicians take into account the radiation risks when assessing the benefit to their patients.

The number of CT scans is remarkable: a recent study of nearly 1 million nonelderly adults showed that 70% received CT scans during the 3-year period of study (2005-2007).1 There were an estimated 72 million CT scans conducted in 2007 alone.2 The doses of radiation from them also are eye opening. Although most patients receive relatively low doses from their scans, nearly 20% of the study's population received "moderate" exposures of between 3 and 20 mSv, and some 2% (translating to as many as 1.4 million patients nationwide) were exposed to "high" and "very high" doses of 20 mSv to more than 50 mSv.

What risks, then, are posed by radiation exposure from CT scans, and are such risks justified?
Two studies in this issue of the Archives help inform this discussion by providing actual effective radiation doses in the most commonly used CT scans and the cancer risks associated with this radiation. Smith-Bindman and colleagues3 collected actual data on radiation dosages for the most commonly used CT scans at 4 institutions in the San Francisco Bay area in California in 2008. They found a surprising variation in radiation dose—a mean 13-fold variation between the highest and lowest dose for each CT type studied (range, 6- to 22-fold difference across study types). There was no discernable pattern to the variation, which occurred within and across institutions. The investigators found a median effective dose of 22 mSv from a typical CT coronary angiogram and 31 mSv for a multiphase abdomen-pelvis CT scan. At one institution, exposure was a staggering 90 mSv for a multiphase abdomen-pelvis CT scan.

Even the median doses are 4 times higher than they are supposed to be, according to the currently quoted radiation dose for these tests. Just 1 CT coronary angiogram, on average, delivers the equivalent of 309 chest radiographs. From their data, Smith-Bindman et al3 estimated the risk of cancer, taking into consideration age, sex, and study type. By their calculations, 1 in every 270 forty-year-old women undergoing a CT coronary angiogram will develop cancer from the procedure.
In a second study, Berrington de González and colleagues2 determined CT scan use frequency using data from a large commercial insurance database, Medicare claims data, and IMV Medical Information Division survey data. They estimated there were 72 million CT scans performed in 2007. Excluding scans conducted after a diagnosis of cancer and those performed in the last 5 years of life, Berrington de González et al2 projected 29 000 excess cancers as a result of the CT scans done in 2007. These cancers will appear in the next 20 to 30 years and by the authors' estimates, at a 50% mortality rate, will cause approximately 15 000 deaths annually.

In other words, 15 000 persons may die as a direct result of CT scans physicians had ordered in 2007 alone. Presumably, as the number of CT scans increase from the 2007 rate, the number of excess cancers also will increase. In light of these data, physicians (and their patients) cannot be complacent about the hazards of radiation or we risk creating a public health time bomb.

The effort to avoid unnecessary excess cancers must be multifaceted. First, radiation protocols should be improved to eliminate the 13-fold difference in radiation dose for the same CT scan; exposures will be significantly reduced if all institutions were to use the lowest-dose technique. Smith-Bindman and colleagues3 found, for example, that the "usual" protocol sometimes unwittingly increased radiation. The authors offer several techniques to improve the quality of CT scans. In addition, patients should be fully informed about the radiation risk; it is unlikely that many patients now appreciate that a single CT scan may represent the radiation equivalent of hundreds of chest radiographs.

A popular current paradigm for health care presumes that more information, more testing, and more technology inevitably leads to better care. The studies by Berrington de González et al2 and Smith-Bindman et al3 counsel a reexamination of that paradigm for nuclear imaging. In addition, it is certain that a significant number of CT scans are not appropriate. A recent Government Accountability Office report on medical imaging, for example, found an 8-fold variation between states on expenditures for in-office medical imaging; given the lack of data indicating that patients do better in states with more imaging and given the highly profitable nature of diagnostic imaging, the wide variation suggests that there may be significant overuse in parts of the country.4 For example, a pilot study found that only 66% of nuclear scans were appropriate using American College of Cardiology criteria—the remainder were inappropriate or uncertain.5

The articles in this issue make clear that there is far more radiation from medical CT scans than has been recognized previously, in amounts projected to cause tens of thousands of excess cancers annually. Also, as these scans have become more sensitive, incidental findings lead to additional testing (and often more radiation), biopsies, and anxiety. Although a guiding principle in medicine is to ensure that the benefit of a procedure or therapy outweighs the risk, the explosion of CT scans in the past decade has outpaced evidence of their benefit. Although there are clear instances when CT scans help determine the treatment course for patients, more and more often patients go directly from the emergency department to the CT scanner even before they are seen by a physician or brought to their hospital room. To avoid unnecessarily increasing cancer incidence in future years, every clinician must carefully assess the expected benefits of each CT scan and fully inform his or her patients of the known risks of radiation.

AUTHOR INFORMATION
Correspondence: Dr Redberg, Editor, Archives of Internal Medicine, University of California, San Francisco, 505 Parnassus, M1180, San Francisco, CA 94143-0124 (redberg@medicine.ucsf.edu ).
Financial Disclosure: None reported.

REFERENCES
1. Fazel R, Krumholz HM, Wang Y; et al. Exposure to low-dose ionizing radiation from medical imaging procedures. N Engl J Med. 2009;361(9):849-857. FREE FULL TEXT
2. Berrington de González A, Mahesh M, Kim K-P; et al. Projected cancer risks from computed tomographic scans performed in the United States in 2007. Arch Intern Med. 2009;169(22):2071-2077. FREE FULL TEXT
3. Smith-Bindman R, Lipson J, Marcus R; et al. Radiation dose associated with common computed tomography examinations and the associated lifetime attributable risk of cancer. Arch Intern Med. 2009;169(22):2078-2086. FREE FULL TEXT
4. US Government Accountability Office. Medicare Part B Imaging Services: Rapid Spending Growth and Shift to Physician Offices Indicate Need for CMS to Consider Additional Management Practices. Washington, DC: US Government Accountability Office; June 2008:21-22. Publication GAO-08-452. http://www.gao.gov/new.items/d08452.pdf. Accessed September 27, 2009.
5. Hendel RC. Evolving concepts of cardiac SPECT, PET, and CT: appropriateness criteria for SPECT/CT. http://www.acc.org/education/programs/brochures/pdfs/nuccardnew_07/fri%20815am%20hendel%20ac%202.pdf. Accessed October 28, 2009.

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Projected Cancer Risks From Computed Tomographic Scans Performed in the United States in 2007
Amy Berrington de González, Mahadevappa Mahesh, Kwang-Pyo Kim, Mythreyi Bhargavan, Rebecca Lewis, Fred Mettler, and Charles Land
Arch Intern Med. 2009;169(22):2071-2077.
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Radiation Dose Associated With Common Computed Tomography Examinations and the Associated Lifetime Attributable Risk of Cancer
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[Rich66]

I remember a recent article talking about huge overages in radiation from CTs at a VA hospital.
Seems to me whether it's false positive/negative mammos or cumulative CT exposure, there's need for some better, cheaper and healthier imaging options. But even in early stage, there is the issue of catching a recurrence in an organ at a point where it can be dealt with surgically. Might outweigh the risk from exposure. In the ER, there might be pressure to over-image for liability reasons.

[Chelee]

It wasn't long ago when heard on the nightly news about the Cedars-Sinai & VA hospitals having some serious radiation overdoses with their CT machines. The one at Cedars Sinai had been set at 8 times higher then normal. They said someone should of noticed but no one did. I just dug up a link to it.

http://articles.latimes.com/2009/oct/14/local/me-cedars-sinai14

Heres another article on Cedar Sinai where this poor guy said his hair fell out and left a bald circle on top of his head. No excuse for this and concerns me more so since I've had far too many CT scans. We have no way of knowing if they check these machines regularly?

http://www.scpr.org/news/2009/11/02/patients-accuse-cedars-sinai-medical-center-not-di/ (http://www.scpr.org/news/2009/11/02/patients-accuse-cedars-sinai-medical-center-not-di/)

The statment belows says it all.

>>>Newkirk said yesterday in a statement, "This isn't just a Cedars-Sinai problem. We believe that because of the way the machine is manufactured and explained to medical users, there is a very good chance that this same situation has been or is being played out in radiology departments across the country. We have no idea how many people have been overdosed with radiation."<<<

This is recent news from Dec. 3rd about a 3rd LA hospital having radiation over doses with a CT. Check out the damage on this womans head. Its bad enough she was worried about a stroke, now she has to worry about brain tumors, cancer and who knows what else.

http://www.latimes.com/news/local/la-me-ctscan8-2009dec08,0,406924.story (http://www.latimes.com/news/local/la-me-ctscan8-2009dec08,0,406924.story)

I know I've expressed my concerns many times to the tech's & my doctors when I'm just getting a regular x-ray. But the techs and doctors always tell me it's nothing to worry about. I disagree since I can't help but wonder if all the yrs as a child that I had x-rays for my scoliosis if it wasn't the cause of my breast cancer? (Another concern...if they DID over expose you...would they call and tell you about it? Not if they didn't have too.)

Chelee

[Rich66]

It would be cool if patients could buy a simple clip on rad dose counter.

[CLTann]

Hi All,

I am encouraged by the outpouring of alarm and concern by so many. The real need is to ask the medical community to comply a requirement that all patients must have a permanent badge, indicating the true cumulative radiation All nuclear energy plant personnel wear them. For medical patients, the design must be modified so that the badge also reflect the actual radiation received at the treatment areas. The badge must be a life-time meter to show all past radiations from all sources in the past, not only at the present hospitals. For patients who do not have past records (most of us are in this category), an impartial estimate of past exposure can be added to the badge history. Doctors and hospitals are responsible for the abnormal increase in the dosage record for its treatment. Fines and compensation to the patients are mandatory if the treatment dosages significantly exceed a certain standard. Only by imposing fines for irresponsible maintenance of machines and careless radiation dosages will the control of dosages be correctly policed. The way it is presently done is a total chaos with no one watching out for the safety of patients. I really don't think it is that difficult to design such a badge. In fact, this could be a very profitable business to go into.

My best wishes for all : Merry Xmas and happy new year.

[Jackie07]

I know I'm always worried about too much radiation. Especially since my bc dx. I hate to think about all the CT scans I've had along with who knows how many x-rays on top of all that. This article I posted a link to does mention they are working on developing a low-dose CT scanner. They sure can't do that soon enough for me.

http://www.msnbc.msn.com/id/34420356/ns/health-cancer/ (http://www.msnbc.msn.com/id/34420356/ns/health-cancer/)

Chelee

[I think (hope :) Chelee probably wouldn't mind my appending her new thread here. Just thought it's too important to be hidden.]