Breast cancer survivors should be aware of the dangers of gaining more weight because it increases the chance of the disease returning.
According to team led by Dr. Alpa Patel, who directs the Cancer Prevention Study-3 at the American Cancer Society, "Longer leisure time spent sitting was associated with a higher risk of total cancer risk in women, and specifically with multiple myeloma, breast and ovarian cancers, Philly noted.
But sitting time was not associated with cancer risk in men."
One doctor noted that the message from the study is clear.
"Encouraging individuals across all categories of weight to reduce sitting time would have an impact on their physical activity, with beneficial effects on cancer and other chronic diseases," Dr. Paolo Bofetta, a professor of preventative medicine at the Icahn School of Medicine at Mount Sinai, in New York City said.
Another study have hinted that breast cancer survivors tend to gain weight after their diagnosis and treatment, but the reason is not yet known. Citing that breast cancer rates tend to rise around menopause, doctors were unsure whether the weight gain was part of normal aging as well as changes in women's reproductive status or there's something about cancer that made patients more vulnerable to gaining weight.
Researchers compared a group of women who survived breast cancer with a similar group of women who did not have the disease in a new study published in Cancer Epidemiology, Biomarkers & Prevention.
All women were at higher risk of developing breast cancer because of family history, according to records on Time.
Despite adjusting for the influence of age, menopause and other factors, the scientists found that those who survived breast cancer did indeed gain more weight. The breast cancer survivors gained almost four pounds more, on average, within five years of their diagnosis as compared to those who didn't have cancer.
Those who were treated with chemotherapy among these women were twice as likely to gain weight, about 11 pounds more on average as compared to women who were treated with hormone-based therapies and women who didn't have cancer.
There are some evidence showing that survivors who gain weight have a greater risk of their cancer coming back.
"The breast cancer survivors gained more weight, significantly more weight, in the four year follow-up," says Amy Gross, a Ph.D candidate at the Johns Hopkins Bloomberg School of Public Health and an author of the paper published in "Cancer Epidemiology, Biomarkers & Prevention."
While weight is suspected in possibly playing some role in certain cancers, this study is among the first to focus on effect cancer itself, and treatments for cancer might have on changing metabolism, inflammation, the immune system and other body functions to make weight gain more likely.
The researchers, led by Dr. Kala Visvanathan, director of clinical cancer genetics and prevention service at the Johns Hopkins Kimmel Cancer Center followed the women for four years. The researchers compared their weight changes from diagnosis onward. The team plans to continue to follow the women for a longer period of time to track other patterns in weight.
"Obviously treatment [for the cancer] is a priority," Visvanathan noted. "But these findings show that it's also important to take note of weight changes, especially for women getting chemotherapy. Chemotherapy treatment usually goes for six months or a year, so monitoring weight in that time and taking steps to intervene if weight is clearly increasing is important."
