by Diana Barnes-Brown
A new study from Maastricht University in The Netherlands and published in the November 3, 2004 Journal of the American Cancer Institute has shown a connection between endometrial cancer and factors such as physical inactivity, obesity, and height.
Endometrial cancer, or cancer of the lining of the uterus, is the most common reproductive cancer affecting women, usually those over the age of 50. It can be diagnosed with the help of a biopsy (tissue sample) and, as with many cancers, it can be treated if caught early in its progress. Usually, treatment for endometrial cancer involves removal of the uterus (hysterectomy) and radiation or chemotherapy. According to the American Cancer Society, there are about 40,000 new cases each year in the United States, and 7,000 of those cases result in death.
Previous studies had indicated a link between endometrial cancer and factors such as obesity and exercise, but Leo Schouten, MD, PhD, and colleagues at Maastricht University set out to elucidate these risk factors further. Schouten and his team analyzed health and medical data of over 60,000 Dutch women, 226 of whom had developed cancer between the years of 1986 and 1995.
What they found was that women who had a body mass index (or BMI, an indicator of a person’s proportion of body fat with respect to the rest of their body mass), and found that women who were obese, displaying a BMI of 30 or above, were close to five times as likely to develop endometrial cancer than those with a normal BMI of between 20 and 22.9, which is within the normal range.
Women who had a BMI of 25 or above at 20 years of age were no more likely to develop endometrial cancer than those with a BMI of 20-22.9 at the same age. On the other hand, those with BMIs less than 20 had a slightly lower risk.
“Our study confirms that BMI is strongly related to endometrial cancer risk,” wrote Schouten and his team regarding the findings. The researchers speculate that the higher levels of estrogen and insulin found in obese women, may be responsible for the increased risk.
Women over 5’9” also had a higher risk than women who were shorter than 5’3”, though the researchers are puzzled as to why this was the case.
The other major factor in determining women’s risk levels for endometrial cancer was physical activity. Schouten and his team found that women who reported 90 or more minutes per day of exercise had a reduced risk of endometrial cancer, while those who got less than 30 minutes of exercise per day had an increased risk.
“Exercise” was defined by the researchers to include sports, recreational biking or walking, dog walking, gardening, household chores, and commutes by foot or by bike, while strenuous or active jobs were not included.
Schouten and his team wrote that the findings about exercise and obesity echoed findings of previous studies linking these factors to endometrial cancer.