Connection Between Obesity and Breast Cancer Prognosis: More Data Emerge

By: Celeste L. Dixon
Posted: Wednesday, November 1, 2023

An association seems to exist between obesity and inferior breast cancer outcomes, according to data published in Cancer & Metabolism. The study, conducted by Signe Borgquist, MD, PhD, of Aarhus University, Denmark, and colleagues, involved more than 1,000 patients with breast cancer followed for a median of about 11 years, 263 who experienced recurrence of the disease.

Patients “with obesity and low socioeconomic position, a large breast tumor, breast cancer of high histological grade, estrogen receptor [ER]-negative breast cancer, and/or patients intended to be treated with chemotherapy were at higher risk of [recurrence] and mortality compared to similar patients with healthy weight,” the team reported. Further, identifying “these vulnerable groups” among patients with breast cancer may help to create improved screening and/or treatment interventions for them, the authors suggested.

Patients were all part of the Malmö [Sweden] Diet and Cancer Study; it enrolled men as well as 17,035 women between 1991 to 1996, and all participants’ body mass index (BMI), waist circumference, and body fat percentage were measured upon enrollment. The 1,099 women with incident invasive breast cancer were identified between 1991 and 2014.

Obesity according to BMI (hazard ratio [HR] = 1.44), waist circumference (HR = 1.31), and body fat percentage (HR = 1.41) was associated with an increased risk of breast cancer recurrence compared with healthy weight. Additionally, obesity was more strongly associated with recurrence in patients with low socioeconomic status (HR = 2.55), tumors measuring more than 20 mm (HR = 2.68), ER-negative breast cancer (HR = 3.13), and with adjuvant chemotherapy (HR = 2.06).

“While previous research has established that obesity is associated with poorer outcomes in [ER]-positive breast cancer, our study suggests this association may be even stronger in estrogen-independent breast cancer.”

Disclosure: The study authors reported no conflicts of interest.

Cancer & Metabolism

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