Weight Loss Tied to Worse Breast Cancer Outcomes
Baseline body mass index tied to outcomes, with obesity linked to poorer outcome
MONDAY, March 8, 2021 (HealthDay News) -- Weight loss during treatment and over two years of follow-up negatively impacts clinical outcomes among women with human epidermal growth factor receptor 2 (HER2)-positive early breast cancer, according to a study published in the February issue of the Journal of the National Comprehensive Cancer Network.
Samuel Martel, M.D., from Université de Sherbrooke in Greenfield Park, Quebec, Canada, and colleagues assessed the impact of body mass index (BMI; measured at baseline and at two years) on outcomes of 8,381 patients with HER2-positive early breast cancer. Weight gain and weight loss were classified as more than or less than 5 percent.
At baseline, 2.2 percent of patients were underweight, 45.3 percent were normal weight, 32.1 percent were overweight, and 20.4 percent were obese. The researchers found that being obese at baseline was associated with a significantly worse distant disease-free survival (DDFS; adjusted hazard ratio [aHR], 1.25; 95 percent confidence interval [CI], 1.04 to 1.50) and overall survival (aHR, 1.27; 95 percent CI, 1.01 to 1.60) compared with being normal weight. However, there was no significant difference in DFS (aHR, 1.14; 95 percent CI, 0.97 to 1.32). Two-year weight loss was associated with significantly poorer DFS (aHR, 1.34; 95 percent CI, 1.05 to 1.71), DDFS (aHR, 1.46; 95 percent CI, 1.07 to 1.98), and overall survival (aHR, 1.83; 95 percent CI, 1.18 to 2.84). Outcomes were influenced by hormone receptor and menopausal status but not anti-HER2 treatment type. Toxicities were more frequent in obese patients.
"Our findings suggest that dietary counseling should be part of survivorship care programs," the authors write.
Several authors disclosed financial ties to the pharmaceutical industry.