MONTREAL, QC and WASHINGTON, DC, June 18 /CNW Telbec/ - A new study of
nearly 6,800 morbidly obese patients shows that those who had bariatric
surgery reduced the risk of developing cancer by about 80 percent, with breast
cancer and colon cancer showing the greatest reductions. The study was
presented today here at the 25th Annual Meeting of the American Society for
Metabolic & Bariatric Surgery (ASMBS).
Researchers from McGill University in Montreal, Quebec, Canada compared
1,035 patients who had bariatric surgery between 1986 and 2002 with
5,746 patients who did not have surgery, matching them by age, gender, and
duration of morbid obesity diagnosis. None of the patients in either group had
previously been diagnosed with cancer.
A total of 21 patients (2%) were diagnosed with cancer in the surgery
group while 487 patients (8.5%) were diagnosed with cancer in the non-surgical
group during the five-year follow up period. A patient was considered to have
cancer if at least one mention of the diagnosis or treatment was detected in
hospital or physician records. Patients who had bariatric surgery lost on
average more than 67 percent of their excess body weight.
"The connection between obesity and several cancers is well established,"
said Nicholas Christou, MD, PhD, the study's lead author and Director of
Bariatric Surgery and Professor of Surgery at McGill University. "This is one
of the first studies to suggest that bariatric surgery may prevent the
development of cancer in a statistically and clinically significant percentage
of people who are morbidly obese."
The incidence of breast cancer was reduced by 85 percent and the
incidence of colon cancer was reduced by 70 percent in the bariatric surgery
group. In the surgery group, 12 people were diagnosed with breast cancer and
two were diagnosed with colon cancer, while 362 were diagnosed with breast
cancer and 35 were diagnosed with colon cancer in the non-surgical group.
The incidence of other cancers was also reduced though they did not
approach clinically significant levels due to the low number of patients
reporting. The incidence of pancreatic cancer was reduced by 70%; skin cancer
by 60%; uterine cancer by 15%; and non-Hodgkin's lymphoma by 50%. According to
the American Cancer Society, being overweight or obese increases the risk of
several cancers, including cancers of the breast (among women past menopause),
colon, esophagus, kidney, and other organs. Each year about 550,000 Americans
die of cancer with one-third of these deaths linked to diet, lack of physical
activity and being overweight.(1),(2)
In 2007, the ASMBS reported that an estimated 205,000 people in the U.S.
had bariatric surgery. According to guidelines issued by the National
Institutes of Health (NIH), bariatric surgery is indicated for people with a
body mass index (BMI) of 35 or more with an obesity-related condition or a BMI
of 40 or more. People who are morbidly obese are generally 100 or more pounds
The most common methods of bariatric surgery are laparoscopic gastric
bypass and laparoscopic adjustable gastric banding (LAGB). In gastric bypass,
the stomach is reduced from the size of a football to the size of a golf ball
and food is made to bypass part of the small intestine. In LAGB, a silicone
band is wrapped around the upper part of the stomach to restrict the amount of
food the stomach can hold. The amount of restriction is adjusted by adding or
removing saline from the band.
Two landmark studies, published in the New England Journal of Medicine in
August 2007, showed patients with morbid obesity who had bariatric surgery
lost significant weight and are significantly less likely to die from heart
disease, diabetes and cancer seven to 10 years following the procedure than
those who did not have surgery.(3),(4) A 2004 study in the Journal of the
American Medical Association showed that bariatric surgery resolved or
improved type 2 diabetes in 86 percent of patients and resolved sleep apnea in
more than 85 percent of patients(5).
The Agency for Healthcare Research and Quality (AHRQ) recently reported
that bariatric surgery is safer than ever. The risk of death from bariatric
surgery has declined from 0.89 percent in 1998, to 0.19 percent in 2004.(6)
About 64 million or 32 percent of adults in the U.S. are considered
obese, which is associated with many other diseases and conditions including
type 2 diabetes, heart disease, sleep apnea, hypertension, asthma, cancer,
joint problems and infertility. The direct and indirect costs to the
healthcare system associated with obesity are about $117 billion annually.
The ASMBS is the largest organization for bariatric surgeons in the
world. It is a non-profit organization that works to advance the art and
science of bariatric surgery and is committed to educating medical
professionals and the lay public about bariatric surgery as an option for the
treatment of morbid obesity, as well as the associated risks and benefits. It
encourages its members to investigate and discover new advances in bariatric
surgery, while maintaining a steady exchange of experiences and ideas that may
lead to improved surgical outcomes for morbidly obese patients. For more
information on the ASMBS, visit www.asmbs.org.
(3) Sjvstrvm L, Narbro K, Sjvstrvm CD, et al. Effects of bariatric
surgery on mortality in Swedish obese subjects. N Engl J Med 2007;
(4) Adams TD, Gress RE, Smith SC, et al. Long-term mortality after
gastric bypass surgery. N Engl J Med 2007:357:753-61.
(5) Buchwald Henry, et al. Bariatric Surgery: A Systematic Review and
Meta-Analysis. JAMA. 2004; 292: 1724-1737.
(6) Zhao, Y. (Social and Scientific Systems, Inc.), and Encinosa, W.
(AHRQ). Bariatric Surgery Utilization and Outcomes in 1998 and 2004.
Statistical Brief No.23. January 2007. Agency for Healthcare and
Research Quality, Rockville, Md.
For further information:
For further information: Hélène Hains, (514) 825-0308