Video: Large, Multi-Center Trial Demonstrates Comparable Accuracy for Virtual
Colonoscopy and Standard Colonoscopy
PHILADELPHIA, Sept. 17 /PRNewswire/ -- Computerized tomographic (CT)
colonography, also known as virtual colonoscopy, is comparable to standard
colonoscopy, which uses a long, flexible tube with a camera to view the lining
of the colon, in its ability to accurately detect cancer and precancerous
polyps and could serve as an initial screening exam for colorectal cancer,
according to the results of the American College of Radiology Imaging Network
(ACRIN) National CT Colonography Trial.
To view the Multimedia News Release, go to:
http://www.prnewswire.com/mnr/acrinctc/34639/
(Photo: http://www.newscom.com/cgi-bin/prnh/20080917/NYW148 )
CT colonography employs virtual reality technology to produce a
three-dimensional visualization that permits a thorough and minimally invasive
evaluation of the entire colon and rectum. The ACRIN trial, sponsored by the
National Cancer Institute (NCI), part of the National Institutes of Health
(NIH), enrolled more than 2,600 patients at 15 sites nationwide. It is the
largest multi-center study to compare the accuracy of state-of-the-art CT
colonography to the gold standard of conventional colonoscopy. The results of
this study are published in the Sept. 18, 2008, issue of the New England
Journal of Medicine.
"CT colonography could be adopted into the mainstream of clinical practice
as a primary option for colorectal cancer screening. We hope that this
additional, less-invasive option for cancer screening will lead more people to
get screened and will ultimately result in fewer deaths from colorectal
cancer," said ACRIN National CT Colonography Trial principal investigator C.
Daniel Johnson, M.D., of the Mayo Clinic in Scottsdale, Ariz.
Colorectal cancer is the third most frequently diagnosed cancer and second
leading cause of cancer death in men and women in the United States. Although
screening recommendations vary somewhat, many recommend that adults aged 50
and older in the general population receive a colonoscopy every 10 years or
more frequently, depending on known risk factors. Yet, despite the known
benefits of screening, studies indicate that the majority of Americans age 50
and older are not being screened for the disease.
"Imaging advances such as virtual colonoscopy are an important step
forward that could potentially increase the number of people who would agree
to be screened. We hope, through continued imaging research and the
development of molecular diagnostic techniques, that we will continue to
improve our screening options in the years ahead and, as a result, continue to
see a decline in the incidence of colorectal cancer," said NCI Director John
E. Niederhuber, M.D.
"Previous single-site studies had indicated that CT colonography held
promise in screening for colorectal cancer due to its accuracy, safety,
cost-effectiveness, and patient acceptability. However, validation of the
technique across multiple centers and radiologists was needed to provide more
evidence of the exam's viability. The ACRIN trial has now validated that CT
colonography could serve as an initial screening exam for the population in
which screening is indicated," said Mei-Hsiu Chen, Ph.D., trial statistician,
ACRIN Biostatistics and Data Management Center, Brown University, Providence,
R.I.
In the ACRIN trial, the CT colonography findings were evaluated using
standard colonoscopy as the reference standard. CT colonography was found to
be highly accurate for the detection of intermediate and large polyps. Ninety
percent of the polyps 1 centimeter or larger were detected by CT colonography.
Even polyps as small as one half centimeter were detected by CT colonography
with a high degree of accuracy. Since most colon cancers develop from polyps,
and screening to find and remove these polyps can prevent colon cancer, an
opportunity exists to save lives with early detection.
"There are clearly clinical settings in which CT colonography,
colonoscopy, or both tests in combination offer distinct advantages. The most
important advice we can give to patients is to get screened. How they get
screened should be an individual decision based upon discussions between
patients and their providers," said gastroenterologist and study author Paul
Limburg, M.D., Mayo Clinic in Rochester, Minn.
Study participants had to be at least 50 years old, scheduled for a
screening colonoscopy, and not have received a colonoscopy in the past five
years. Each participant had a CT colonography followed by a colonoscopy, with
99 percent of both exams accomplished on the same day. Participants scheduled
for a screening colonoscopy were recruited with assistance from
gastroenterologists at each participating site. Preparation for CT
colonography and colonoscopy both involve taking solutions to clear and
cleanse the colon.
Research advocates played an important role in advising the scientists who
conducted this study. "As the ACRIN patient advocate who worked with the
research team and as a research advocate with C3: Colorectal Cancer Coalition,
I am pleased that CT colonography can be added to the list of screening
options. Having a method that is accurate and comprehensive while being
minimally invasive is needed if we are to succeed in substantially reducing
deaths from colorectal cancers," said Pam McAllister, Madison, Wis.
Click here (http://www.acrin.org/TabID/151/Default.aspx )for further
information about the ACRIN National CT Colonography Trial.
Click here
(http://www.cancer.gov/newscenter/pressreleases/VirtualColonoscopyQA ) to read
the Q&A for this trial.
To arrange an interview with Dr. Johnson, contact American College of
Radiology (ACR) Public Relations manager, Shawn Farley, at 703-648-8936 or
sfarley@acr.org.
Click here (http://www.cancer.gov/cancertopics/types/colon-and-rectal )
for more information regarding colorectal cancer on the National Cancer
Institute Web site.
TV stations Click here
(http://www.prnewswire.com/broadcast/34638/press.html ) (PR Newswire) or visit
The NewsMarket ( www.thenewsmarket.com ) for sound bites, b-roll, and a VNR
package.
SOURCE American College of Radiology Imaging Network (ACRIN)
Shawn Farley, Public Relations Manager, ACRIN, +1-703-648-8936,
sfarley@acr.org; or NCI Press Officers, +1-301-496-6641,
ncipressofficers@mail.nih.gov
