Data from a phase 3 study indicate that weight loss intervention with a telephone-based program appears to be effective across all subgroups of breast cancer survivors.
A weight loss intervention program available via the internet and telephone effectively helped with weight loss among patients with breast cancer who had obesity, according to findings from a phase 3 trial presented during a press briefing prior to the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting.
“Obesity is a poor prognostic factor in early breast cancer,” study author Jennifer Ligibel, MD, a medical oncologist at the Dana-Farber Cancer Institute in Boston, Massachusetts, said in a presentation of the results ahead of the meeting. “Women with obesity at the time of a breast cancer diagnosis have a higher risk of cancer recurrence, cancer-related mortality and overall mortality compared to women with a body mass index [BMI] in the normal range at the time of their breast cancer diagnosis.”
The phase 3 Breast Cancer Weight Loss Trial included 3,136 patients with stage I through III HR-positive, HER2-negative or triple-negative breast cancer who were diagnosed within 14 months from the start of the trial. To be eligible for the trial, they must have a BMI at or above 27 kg/m2—which is in the upper end of the overweight range, according to Ligibel.
Participants were randomly assigned to have health education plus 2 years of telephone-based weight loss (which included 42 calls from a health coach and supplemental workbook and tools) or health education alone. The phone-based weight loss program focused on patients lowering calories and increasing physical activity.
The main goal of the study was to see if there was a difference in invasive disease-free survival, with the key secondary end point being weight change.
Study findings showed that patients in the weight loss intervention group tended to lose more weight than those who just underwent the initial education. At the 6-month mark, those in the intervention group lost an average of 4.4 kg, while those in the control group gained an average of .2 kg. At 12 months, those in the intervention group had an average loss of 4.4 kg again, while the education-only group had an average weight gain of .9 kg.
“This equated to a 5.65% weight differential in the 2 arms, demonstrating significant weight loss which was also clinically significant given that a 3% weight loss is sufficient to improve diabetes and other chronic diseases,” Ligibel said.
When broken down by subgroup, the researchers found that menopausal status and race/ethnicity tended to affect the amount of weight lost. Specifically, post-menopausal women tended to experience a higher percentage of weight change than pre-menopausal women (6.39% vs 4.68%, respectively). Regarding race/ethnicity, African Americans lost an average of 3.74%, while Hispanic patients lost an average of 4.13%, and other ethnicities lost an average of 6.05%.
“However, across all of these subgroups, the weight loss intervention was highly successful in helping patients to achieve meaningful weight loss,” Ligibel mentioned.
Looking ahead, Ligibel said that the Breast Cancer Weight Loss Trial will continue to follow patients to determine if the weight loss has an impact on invasive disease-free survival and other breast cancer outcomes.
“Now that we have demonstrated that our intervention was successful in inducing weight loss, we will be able to determine whether losing weight after a breast cancer diagnosis improves outcomes in these women,” Ligibel said.
Ligibel J. Effect of a telephone-based weight loss intervention (WLI) on weight at 12-months in women with early breast cancer: Results from the Breast Cancer Weight Loss (BWEL) trial. Presented at: 2023 ASCO Annual Meeting. Abstract 12001.