Increasing Number of CT and PET Scans Raise Cancer Risk Concerns

Comments Off on Increasing Number of CT and PET Scans Raise Cancer Risk Concerns





 

A new research study reveals a striking increase in the number of CT and PET scans being performed, resulting in increased radiation exposure levels


 

 

INCREASING NUMBER OF CT AND PET SCANS RAISE CANCER RISK CONCERNS

Last week, I discussed new data regarding CT scans in children, and the potential increase in lifetime cancer risk associated with these scans.  This week, I will continue with this general theme by reviewing a new clinical study, published in the Journal of the American Medical Association, that documents the continuing rise in the number of medical imaging studies being performed, including computed tomography (CT) scans.  In view of this continuing increase in the number of medical imaging exams being performed, public health experts are concerned that cancer rates may also rise.

As I discuss in my bestselling book, A Cancer Prevention Guide for the Human Race, exposure to medical x-rays, and particularly exposure to radiation from CT scans, is an under-appreciated cancer risk factor.  Based upon conservative estimates, exposure to medical radiation is thought to cause approximately 2 percent of all new cancer cases, and most of this medical x-ray exposure comes from CT scans and positron emission tomography (PET) scans.

It is important to acknowledge that, when ordered and performed appropriately, CT scans, PET scans, and other medical imaging studies offer enormous potential benefits to patients and their doctors, and the benefits of medical imaging far outweigh the risks in such cases.  However, since the advent of CT scans and other forms of advanced medical imaging, many physicians have increasingly come to rely upon these imaging studies when other methods of clinical diagnosis that do not expose patients to large doses of ionizing radiation will work just as well.

In this new clinical study, the electronic medical records systems of 6 large integrated health care systems in the United States were analyzed.  In this very large study, between 1 and 2 million patient records were reviewed every year between 1996 and 2010.  All patient-members enrolled in the following health care organizations during this 15-year period were evaluated:Group Health Cooperative in Washington State; Kaiser Permanente in Colorado, Georgia, Hawaii, Oregon, and Washington; and the Marshfield Clinic and Security Health Plan in Wisconsin.

The focus of this study was on Health Maintenance Organizations (HMOs), because these organizations typically have very robust utilization management systems that are designed to monitor for, and prevent, wasteful or inappropriate medical studies, including unnecessary medical imaging exams.  Given that the use of advanced medical imaging studies has skyrocketed in the fee-for-service world in recent years, the authors of this new study sought to assess trends in the use of advanced medical imaging studies among HMOs, specifically.

During the 15-year study period, the patients of these 6 HMOs underwent 31 million medical imaging exams, equal to an average of 1.2 imaging tests per year for every patient-member.  More than one-third of these medical imaging exams were advanced medical imaging studies (CT scans, MRI scans, PET scans, and ultrasound scans).  When measured on an annual basis during the 15 year duration of this study, CT scan exams increased by 8 percent per year, while MRI scans increased by 10 percent per year.  PET scans, which are typically combined with CT scans, increased by a whopping 57 percent per year from 2004 through 2010.  (Ultrasound scans, which, like MRI scans, do not expose patients to ionizing radiation, increased by 4 percent per year.)

Of particular interest to me, as a cancer prevention expert was the finding that the increased use of CT scans resulted in a per capita doubling of radiation exposure doses among the patient-members of these 6 HMOs.  Moreover, the proportion of patient-members who received high and very high medical radiation doses also doubled during the course of this study, reflecting the increased use of high-energy medical imaging studies, including, primarily, CT scans and CT-PET scans.  Indeed, by 2010, 7 percent of these HMO patient-members received medical imaging studies that placed them within the “high annual radiation exposure” category (> 20-50 millisieverts, or mSv), while 4 percent of patients received “very high annual radiation exposure” doses of medical radiation (> 50 mSv).

Once again, it is important to stress that advanced medical imaging is a very powerful tool that can provide physicians with essential diagnostic information for many of their patients.  However, experts in the fields of Radiology and Public Health have become very concerned, in recent years, regarding the questionable indications for advanced imaging scans in many cases.  Indeed, there is the sense that these powerful diagnostic scans are too easily and too quickly ordered in many cases, and without compelling clinical justification.  Therefore, it behooves both patients and their physicians to ask a simple but very important question:  Does the likely benefit of undergoing a CT scan or CT-PET scan outweigh the possible associated risks?  If the answer to this question is no, then such scans should not be performed.


At this time, 8.2 percent of Americans are unemployed.  According to the Bureau of Labor Statistics, however, the unemployment rate for veterans who served on active duty between September 2001 and December 2011 is now more than 12 percent.  A new website, Veterans in Healthcare, seeks to connect veterans with potential employers.  If you are a veteran who works in the healthcare field, or if you are an employer who is looking for physicians, advanced practice professionals, nurses, corpsmen/medics, or other healthcare professionals, then please take a look at Veterans in Healthcare.


For a groundbreaking overview of cancer risks, and evidence-based strategies to reduce your risk of developing cancer, order your copy of my bestselling book, “A Cancer Prevention Guide for the Human Race,” from AmazonBarnes & NobleBooks-A-MillionVroman’s Bookstore, and other fine bookstores!

Within one week of publication, A Cancer Prevention Guide for the Human Race was ranked #6 among all cancer-related books on the Amazon.com “Top 100 Bestseller’s List” for Kindle e-books. Within three months of publication, A Cancer Prevention Guide for the Human Race was the #1 book on the Amazon.comTop 100 New Book Releases in Cancer” list.




Disclaimer:  As always, my advice to readers is to seek the advice of your physician before making any significant changes in medications, diet, or level of physical activity


 

Dr. Wascher is an oncologic surgeon, professor of surgery, cancer researcher, oncology consultant, and a widely published author


 

I and the staff of Weekly Health Update would again like to take this opportunity to thank the more than 100,000 health-conscious people from around the world who visit this premier global health information website every month.  (More than 1.3 million pages of high-quality medical research findings were served to the worldwide audience of health-conscious people who visited Weekly Health Update in 2011!)  As always, we enjoy receiving your stimulating feedback and questions, and I will continue to try and personally answer as many of your inquiries as I possibly can.


 




Bookmark and Share





































Post to Twitter

New Government (USPSTF) Warning on Hormone Replacement Therapy Risks






 

A new report by a U.S. Government task force (USPSTF) recommends against the use of hormone replacement therapy due to serious health risks.



 

NEW GOVERNMENT (USPSTF) WARNING ON HORMONE REPLACEMENT THERAPY RISKS

As I discuss in my bestselling book, A Cancer Prevention Guide for the Human Race, there is now solid evidence that the most commonly used form of hormone replacement therapy (HRT) is associated with a significant increase in the risk of developing breast cancer, and that risk continues to rise with the duration of HRT use.

Like many cancer experts, I have taken issue with some of the U.S. Preventive Services Task Force’s (USPSTF) recent revisions of longstanding cancer screening recommendations, including, particularly, their 2009 recommendation that annual screening mammograms be started later in life than most experts have recommended (and continue to recommend), and performed less frequently among middle-aged women than most experts have also recommended.  More recently, in 2011, the USPSTF’s blanket recommendation that routine PSA screening for prostate cancer be largely abandoned has not been warmly embraced by me, nor by many other cancer prevention experts, given that we still cannot determine, in advance, which men with prostate cancer will be helped by treatment for this disease and which men will not benefit (and, hence, may actually even be harmed) by being treated because they have an indolent form of prostate cancer that poses no threat to their lives (Does PSA Testing for Prostate Cancer Save Lives?).

Now, the USPSTF is weighing in on another controversial cancer-related issue: hormone replacement therapy. Prior to 2002, more than half of all American women took some form of HRT to treat the common symptoms of menopause, including hot flashes, night sweats, vaginal dryness, and irritability.  As I discuss in my forthcoming book on the tragic history of HRT, The Manufactured Myths of Menopause and Hormone Replacement Therapy: A Legacy of Suffering and Death, the intentionally deceptive multi-decade marketing of HRT drugs as a panacea for the both the real and imagined consequences of menopause, and the skillful (if duplicitous) portrayal of menopause as a pathological disease that renders its “victims” something less than feminine, was only recently revealed to be a collection of gross distortions (to put it mildly) on the part of the dominant manufacturer of HRT medications.  Thanks to the landmark findings of the enormous Women’s Health Initiative study, which was published in the Journal of the American Medical Association in 2002, we now know that long-term HRT use is clearly associated with an increased risk of multiple and serious health problems, including an increased risk of breast cancer.

The USPSTF is now about to weigh-in on the issue of HRT, in a paper that is to be released in the June 4th issue of the Annals of Internal Medicine.  Unlike their other recent controversial pronouncements, however, I actually find the USPSTF’s new recommendations against the routine use of HRT to be very close to my own recommendations, and so I am including their review of the existing clinical research data on HRT in this column.

After comprehensively reviewing the data from 9 different prospective, randomized, placebo-controlled, blinded clinical studies (including the massive Women’s Health Initiative study), the USPSTF study group determined that both estrogen-progesterone (combination) HRT and estrogen-only HRT significantly increased the risk of stroke, potentially fatal blood clots (venous thromboembolic disease), gallstones, and urinary incontinence.  Estrogen-progesterone (combination) HRT was also, once again, shown to be associated with a significantly increased risk of breast cancer, as well as a probable increase in the risk of dementia.  (On the other hand, estrogen-only HRT, which can only be taken by women who have previously undergone hysterectomy, appears to actually decrease the risk of developing breast cancer, while both types of HRT also appear to reduce the risk of osteoporosis-associated bone fractures.)

Based upon the increasingly large amount of available clinical research data, HRT, of any type, cannot currently be recommended for routine long-term use, given the multiple and significant health risks associated with both estrogen-only and estrogen-progesterone forms of HRT.  After decades of intentionally misleading advertising by the manufacturer of the two most frequently prescribed forms of HRT, and the manufacturer’s intentional co-opting of numerous women’s physicians over the years, the true risks associated with the long-term use of HRT have now become abundantly clear.  I will have much more to say about this cautionary tale when The Manufactured Myths of Menopause and Hormone Replacement Therapy: A Legacy of Suffering and Death is published in early 2013….


For a groundbreaking overview of cancer risks, and evidence-based strategies to reduce your risk of developing cancer, order your copy of my bestselling book, “A Cancer Prevention Guide for the Human Race,” from AmazonBarnes & NobleBooks-A-MillionVroman’s Bookstore, and other fine bookstores!

Within one week of publication, A Cancer Prevention Guide for the Human Race was ranked #6 among all cancer-related books on the Amazon.com “Top 100 Bestseller’s List” for Kindle e-books. Within three months of publication, A Cancer Prevention Guide for the Human Race was the #1 book on the Amazon.comTop 100 New Book Releases in Cancer” list.




Disclaimer:  As always, my advice to readers is to seek the advice of your physician before making any significant changes in medications, diet, or level of physical activity


 

Dr. Wascher is an oncologic surgeon, professor of surgery, cancer researcher, oncology consultant, and a widely published author


 

I and the staff of Weekly Health Update would again like to take this opportunity to thank the more than 100,000 health-conscious people from around the world who visit this premier global health information website every month.  (More than 1.3 million pages of high-quality medical research findings were served to the worldwide audience of health-conscious people who visited Weekly Health Update in 2011!)  As always, we enjoy receiving your stimulating feedback and questions, and I will continue to try and personally answer as many of your inquiries as I possibly can.


 







Bookmark and Share





































Post to Twitter

Better Tag Cloud