Obesity linked to worse outcomes in early breast cancer treatment

December 8, 2011

Obesity is associated with worse outcomes overall in early-stage breast cancer, researchers reported at the 2011 CTRC-AACR San Antonio Breast Cancer Symposium, held Dec. 6-10, 2011.

Obesity was linked to shorter time to recurrence (TTR), disease-free survival (DFS) and overall survival (OS). The exception was treatment with endocrine therapy (mainly tamoxifen), in which obesity was associated with a protective effect.

"The findings add to the body of evidence indicating that obesity, in general, increases a patient's chance for having a worse prognosis," said lead researcher Sao Jiralerspong, M.D., Ph.D., an assistant professor of medicine at Baylor College of Medicine.

"Obesity is a probable risk factor for worse outcomes, and ours is the latest study to suggest it has an effect on treatment outcome as well," Jiralerspong said.

Using data from the Lester and Sue Smith at Baylor, Jiralerspong and colleagues examined the link between weight and treatment modality in 4,368 patients treated between 1970 and 1995.

For the group as a whole, data revealed that overweight patients had similar outcomes to normal-weight patients, but had an increased risk for worse TTR, DFS and OS.

Among patients who received no or endocrine therapy, there was a trend for worse in obese patients compared with normal-weight patients.

Obese patients who received chemotherapy fared significantly worse compared with normal-weight patients, "with the magnitude of this effect approaching that of the degree of benefit expected from chemotherapy," Jiralerspong said.

In contrast, overweight patients who received endocrine therapy, predominantly tamoxifen, fared significantly better compared with normal-weight patients.

"Finding that have a better outcome than normal-weight after tamoxifen treatment is surprising. We are examining the possible reasons for this," Jiralerspong said.

He said that obesity could contribute to worse outcomes because of biological factors associated with excess weight, such as higher blood insulin and estrogen levels, inflammation and growth factors secreted by fat cells. But Jiralerspong also added that more research is needed to understand the effect of body mass on adjuvant treatment because of the unexpected findings and because additional agents are in use today compared with the time period studied.

Explore further: Oral bisphosphonate did not improve prognosis for patients with breast cancer

Related Stories

Recommended for you

Combination therapy can prevent cytostatic resistance

November 26, 2015

Researchers at Karolinska Institutet have found a new way of preventing resistance to cytostatics used in the treatment of cancers such as medulloblastoma, the most common form of malignant brain tumour in children. The promising ...

Forecasting the path of breast cancer in a patient

November 23, 2015

USC researchers have developed a mathematical model to forecast metastatic breast cancer survival rates using techniques usually reserved for weather prediction, financial forecasting and surfing the Web.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.