Body Mass and Prognosis
This is a summary from Living Beyond Breast Cancer (www.lbbc.org) about a study presented at the San Antonio Breast Cancer meetings in December. This work, by Ewertz et al, suggests that extra weight may be related to recurrence risk. The bottom line here is that estrogen lurks in fat cells, so, at least in theory, the fewer fat cells we carry, the less estrogen we harbor. Appreciating that diet and weight are very difficult struggles for many women, they are still something that is more or less in our control. Since so much of cancer is totally out of our control, it may be helpful to have goals and challenges that we can tackle.
Body Mass Index Impacts Breast Cancer Prognosis
Danish women with a body mass index of more than 25
who had breast cancer were more likely to have a metastatic recurrence than
those with a lower BMI.
By Mary Alice Hartsock, LBBC Staff; Reviewed by: Carrie Stricker, PhD, RN
Ewertz, M. et al. Effect of Obesity on Prognosis after Early Breast Cancer. Presented at
the 32nd Annual San Antonio Breast Cancer Symposium. December 10, 2009.
After breast cancer treatment, having a body mass index (BMI) of more than 25 (being
overweight or obese) is related to higher likelihood of distant metastasis and poorer survival rates,
results of a recent study indicate.
The study, presented at the 32nd Annual San Antonio Breast Cancer Symposium in
December, was a retrospective study of nearly 19,000 women diagnosed with early-stage breast
cancer in Denmark who were followed for up to 30 years after diagnosis.
The scientists gathered data on 53,816 women from the Danish Breast Cancer Cooperative
Group database. Scientists knew the height and weight of 18,967 of the women. They used this
information to determine their BMI, a measure that helps define healthy and unhealthy body
weights, approximates body fat and is used to predict risk for disease.
The U.S. Department of Health and Human Services National Institutes of Health considers a
person with a BMI of less than 18.5 to be "underweight" and a person of "normal weight" to have
a BMI of 18.5-24.9. The NIH designates a person with a BMI between 25-29.9 as "overweight,"
and a person with a BMI of more than 30 as "obese."
Compared to women with a BMI of less than 25, women with a BMI over 25 were older, more
often postmenopausal, and had larger tumors, more positive lymph nodes, more invasion of
cancer cells into breast tissue and lymph nodes, and more grade III cancers, which indicates
more aggressive growth and characteristics of the cancer cells.
Women who were overweight or obese (BMI of 25 or more) had a greater risk over time of
developing metastatic breast cancer, or cancer that has traveled away from the breast to other
parts of the body such as the bones, liver, lungs or brain. The risk for loco-regional recurrence, or
recurrence in the same area as the original breast cancer, did not increase based on BMI.
In addition, the risk of dying from breast cancer was higher for women with a BMI of 25 or above
than for those with a lower BMI.
Within the first ten years after the original diagnosis, chemotherapy and hormonal therapy
appeared to work similarly well in people of any BMI. But after ten years, the treatment effect did
not last as well for obese women with a BMI of 30 or above, as they had poorer survival in spite of
What Does This Study Mean for Me?
This study suggests that managing your weight could protect you from a recurrence of breast
cancer, or it could help your adjuvant (post-surgical) treatment last longer than it would otherwise.
Exercise also can protect you from other diseases and even improve your mood.
Starting an exercise routine—or continuing one while you are recovering from treatment—can be
challenging, but there are many simple steps you can take to get started. Talk with your doctor or
nurse about a physical fitness routine, and choose fruits, vegetables and lean protein. Develop a
follow-up care plan with your healthcare team, and be diligent about getting your regular
screening mammograms and other follow-up tests. Go to the NIH Web site to calculate your BMI
and to learn more about living a healthful lifestyle. Look for an article on fitness and exercise
soon on our newsletter page.