Exercise helps odds of surviving cancer

About 44 percent of men and 38 percent of women will get cancer at some point in their lives. Our odds of surviving cancer increase dramatically if we get at least 150 minutes a week of moderate aerobic exercise, a British study published this month indicates.

Exercise, according to the MacMillan Cancer Support Center, can reduce the risk of dying from prostate cancer by 30 percent, from breast cancer by 40 percent and from bowel (colorectal) cancer by 50 percent.

A third of the roughly 570,000 cancer deaths in America each year are linked to poor diet, physical inactivity and carrying too much weight, according to the American Cancer Society. Cancer is responsible for nearly a quarter of all deaths in the United States and for most deaths after the age of 40.

Breast cancer is the cancer women are most likely to experience, but they are more likely to die from lung cancer.

Men are most likely to get prostate cancer, lung cancer or colorectal cancer.

The MacMillan Cancer Support Center is one of Britain's largest charities. Its report, "Move More," reviewed the findings of 60 studies on the effects of exercise on cancer.

The report's conclusions clash with the advice many doctors -- including Jane Maher, chief medical officer for the charity -- have given cancer patients for years.

"The advice I previously would have given to one of my patients would have been to 'take it easy,' " Dr. Maher said in a written statement.

The MacMillan Center found in a survey of 400 British health professionals that a majority did not talk to their cancer patients about the benefits of exercise.

"There really needs to be a cultural change so that health professionals see physical activity as an integral part of cancer after-care," Dr. Maher said. "If physical exercise were a drug, it would be hitting the headlines."

Local experts praised the study, with a few caveats.

Jane Raymond, director of the division of medical oncology at Allegheny General Hospital, said she hadn't thought much about exercise and cancer until three years ago, when a paper was presented on it at a breast cancer symposium she attended in San Antonio.

"I was intrigued," she said. "Up to that time, I thought, why should exercise reduce the risk of breast cancer?"

Now, Dr. Raymond said, "I always recommend exercise to my patients."

"Evidence is growing that exercise helps you tolerate the treatment better, helps you recover faster and helps reduce the risk of recurrence," said Josie van Londen, director of the Cancer LiveWell Surivorship Programs at UPMC's Hillman Cancer Center and Magee-Women's Hospital.

A specific physical benefit of exercise for women with breast cancer or who are at risk of getting it is that "women who do more exercise have less estrogen in their system, and it is estrogen that increases the risk of breast cancer," Dr. Raymond said.

Insulin also contributes to breast cancer, she said, and insulin levels also are lowered with exercise.

Overweight women are more at risk, Dr. Raymond said.

"Overweight women have more estrogen circulating," she said. "That's one reason why obesity leads to more breast cancer."

The evidence is strongest that exercise improves the attitude of patients and helps them tolerate the often grueling treatments they must endure, Dr. van Londen said.

"Ninety-five percent of my patients complain of fatigue," Dr. Raymond said. "Exercise is one way to get over that fatigue."

"I don't know how I would have been able to get through all the treatment had I not been exercising," said Kelley Davis, 30, a patient of Dr. Raymond who was diagnosed with breast cancer last year.

Ms. Davis is an ardent runner who ran six miles a day before her diagnosis. She's had to cut that back to three while undergoing treatment.

"Radiation is making me tired," she said, "but I still feel good after I run."

Both Ms. Davis and Talia Piazza, 28, another patient of Dr. Raymond, said the principal benefit of exercise for them was on their attitude.

Exercise "definitely was a big stress reliever," Ms. Davis said. "I felt like I was still accomplishing something, even though everything else in my life wasn't going as planned."

"I think it's just a stress reliever," Ms. Piazza said. "It gives you confidence that you're doing all you can to have a healthy lifestyle."

Ms. Piazza illustrates that you don't have to work out as vigorously as Ms. Davis does to get benefits from exercise. Ms. Piazza gets most of her exercise walking the mile and a half from her home in Bellevue to and from the bus stop on her way to and from work.

Exercise "doesn't need to be anything too strenuous," Ciaran Devane, chief executive officer of the MacMillan Center, said in a statement. "Doing the gardening, going for a brisk walk or a swim all count."

Gardening once or twice a week can reduce the risk of developing lung cancer for former smokers by 40 percent and for lifelong nonsmokers by 50 percent, according to a 2007 study by the M.D. Anderson Cancer Center of the University of Texas.

More studies have to be done to determine what effect exercise may have on reducing the risk of getting cancer in the first place and on increasing the prognosis for long-term survival, Dr. van Londen said.

"Most of what we know is from observational studies, which do show exercise has a positive effect," she said. "But the best evidence is a randomized clinical trial."

Cancer survivors shouldn't race to the gym without first seeking clearance from their oncologist, Dr. van Londen said.

In designing an exercise program, it would be wise, she said, for a cancer survivor to seek guidance from a certified athletic trainer or a physical therapist, especially if the survivor has some physical limitations. The American College of Sports Medicine, working with the American Cancer Society, has developed a program to certify trainers to work specifically with cancer patients.

The American Cancer Society says you should avoid exercise if you have anemia, and you should stay away from heavy weights if you've developed osteoporosis, nerve damage or bone cancer.

First published on August 29, 2011 at 12:00 am