Key clinical point: Recreational physical activity (RPA) before and after the diagnosis of high-risk breast cancer is associated with lower recurrence and mortality.

Major finding: Patients meeting the minimum guidelines (≥150 minutes of moderate-intensity RPA/week) vs. being inactive before and 1 year after diagnosis had a 41% lower risk of recurrence and 49% lower all-cause mortality.

Study details: Analysis of 1,340 patients enrolled in the Diet, Exercise, Lifestyle, and Cancer Prognosis Study (DELCaP), a prospective study ancillary to the phase 3 clinical trial SWOG 0221.

Disclosures: The study was supported by the Breast Cancer Research Foundation, the Roswell Park Comprehensive Cancer Center, and the National Cancer Institute. The authors reported relationships with multiple pharmaceutical companies and/or research organizations.

Citation: Cannioto RA et al. J Natl Cancer Inst. 2020 Apr 2. doi: 10.1093/jnci/djaa046.

COMMENTARY

“The literature supports an association between physical activity and breast cancer, including lower risk of developing breast cancer, reduced risk of recurrence and improved survival. The etiology of this relationship is likely multifactorial and continues to be investigated. In postmenopausal women, physical activity directly lowers plasma estrogen levels and weight loss leads to reduced adipose tissue and subsequent estrogen production. Exercise can also reduce insulin levels and insulin resistance, create an anti-inflammatory environment, and condition the body’s response to oxidative stresses, all features that can favourably affect carcinogenesis. Research has also found that metabolic syndrome impacts survival in triple-negative disease, and physical activity may decrease risk and delay onset of breast cancer in women with a genetic predisposition (BRCA 1/2 carriers). It is important to understand how physical activity can impact breast cancer outcomes so that providers can counsel patients on this modifiable risk factor.”

Erin Roesch, MD

The Cleveland Clinic

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