Morbidly obese patients who undergo weight-loss surgery greatly reduce their risk of cancer, according to a study providing fresh evidence of health benefits from these increasingly common operations.
Researchers from McGill University in Montreal found that the people who underwent bariatric surgery saw reductions in particular in the risk for breast and colon cancer. Many people see dramatic weight loss after such surgery.
People who are deemed morbidly obese typically are at least 100 pounds overweight. The researchers tracked 1,035 such patients who had bariatric surgery for five years. They also monitored 5,746 patients who matched the surgery group in age, sex and weight but did not have this surgery.
Those who underwent bariatric surgery had about an 80 percent lower risk of developing cancer, the study showed.
"The evidence is mounting that weight loss through weight-loss surgery, if you are extremely obese, is extremely beneficial both to your health as well as to your quality of life," Dr. Nicolas Christou, McGill's head of bariatric surgery who led the study, said in a telephone interview on Thursday.
In addition to cutting the incidence of breast cancer by about 85 percent and colon cancer by about 70 percent, those who underwent bariatric surgery also saw reductions in the risk for pancreatic cancer, skin cancer, uterine cancer and non-Hodgkin's lymphoma, the researchers said.
Obesity linked to several cancers
Obesity raises the risk for several types of cancer, including cancers of the breast, colon, esophagus and kidney, as well as numerous other diseases.
The study buttresses findings published last year in the New England Journal of Medicine that obese people who have bariatric surgery have a lower risk of death from heart disease, diabetes as well as cancer compared to obese people who do not have such surgery.
Bariatric surgery alters the digestive system's anatomy to cut the volume of food that can be eaten and digested.
In Christou's study, presented at a meeting of the American Society for Metabolic & Bariatric Surgery, most of the patients had gastric bypass surgery, which leaves the stomach smaller and permits food to bypass part of the small intestine.
"There's an old misconception that this is cosmetic surgery. But actually, people who are overweight don't live as long because a lot of them develop weight-related health problems that shorten their lives. What we see in all these studies is that when people lose the weight, their health gets better," said Dr. Daniel Gagne of the Western Pennsylvania Hospital in Pittsburgh, who presented another study at the meeting.
An estimated 205,000 people underwent bariatric surgery in the United States last year.
Extra health benefits
Other studies unveiled at the meeting also described health benefits in people who lost weight after bariatric surgery.
Gagne's study showed that most patients with asthma and arthritis were able to stop taking steroids to treat the conditions within about a year of having bariatric surgery.
The study involved 49 morbidly obese patients who were taking steroids and other immunosuppressant medications to treat chronic inflammatory diseases and autoimmune diseases.
New York University researchers showed that losing less than half of excess weight within a year of bariatric surgery was enough for patients to see dramatic improvements in type 2 diabetes, hypertension, high cholesterol and sleep apnea.
