Patients with the strongest versus weakest adherence to the cancer prevention lifestyle recommendations experienced a 58% reduction in mortality.
“Although the American Institute of Cancer Research and the American Cancer Society regularly publish lifestyle recommendations for cancer prevention, it is not yet established whether collective adherence to these lifestyle recommendations before, during, and after breast cancer treatment have impacted the risk for recurrence and mortality in patients with breast cancer who are considered high-risk,” explains Rikki Cannioto, PhD, EdD.
For a study published in JAMA Network Open, Dr. Cannioto and colleagues leveraged detailed epidemiological data from a prospective cohort study of 1,340 patients with high-risk breast cancer. Known as the Diet, Exercise, Lifestyle, and Cancer Prognosis (DELCaP) study, the researchers sought to determine whether adherence to cancer prevention recommendations before diagnosis, during treatment, and at 1 and 2 years after treatment was linked with disease recurrence or mortality.
Specific Lifestyle Factors Linked to Survival Outcomes in High-Risk Breast Cancer
“The overarching goal of the study was to examine the relationship between a standardized Lifestyle Index Score (LIS) and high-risk breast cancer survival outcomes,” Dr. Cannioto says. “The LIS was aggregated to include adherence scores for specific individual lifestyle factors over four timepoints.” These lifestyle factors were studied:
- Maintaining a healthy body weight
- Being physically active
- Eating a diet rich in vegetables and fruits
- Limiting consumption of fast food and processed foods
- Limiting consumption of red and processed meat
- Limiting consumption of sugar-sweetened beverages
- Limiting alcohol consumption, and
- Avoiding cigarette smoking
“The key finding of our study was that patients with the strongest versus weakest adherence to the cancer prevention recommendations experienced a 58% reduction in mortality and a 37% reduction in disease recurrence,” Dr. Cannioto says. “The significant and striking associations were consistently observed in patients diagnosed with more aggressive tumors, including triple negative and HER2-positive tumors. Additional analyses designed to assess the contribution of each lifestyle factor in the overall relationship between the LIS and survival outcome revealed that being a never smoker and meeting the minimum physical activity guidelines were the two most important factors.”
Modifiable Lifestyle Factors Are Important Considerations
As time progressed in months, the study team observed that patients with the healthiest lifestyle were less likely to experience a recurrence and more likely to survive; the differences in survival among the groups were statistically significant, according to the study team (Figure).
“These data suggest that modifiable lifestyle factors are important considerations for patient survival,” Dr. Cannioto says. “For clinical oncology care teams, an important takeaway is that consistent data presented herein and in the extant literature support the link between physical activity and improved cancer survival. Likewise, ASCO now recommends that oncology care teams prescribe physical activity to patients undergoing active treatment with curative intent. If patients and cancer survivors are overwhelmed by the minimum physical activity guideline of 150 minutes of PA per week, it is suggested that they focus on moving more throughout the day, sitting less, and trying to achieve some regular exercise on most days of the week. Any regular physical activity is better than being inactive. Walking at a moderate pace would count towards achieving the guideline.”
Dr. Cannioto and colleagues agree that future research investigating the association between adherence to cancer prevention guidelines and cancer survival outcomes in more diverse patient populations is needed. “Moreover, there is a need for additional work designed to identify molecular pathways underlying the link between healthful lifestyles and improved cancer survival,” Dr. Cannioto adds.
