Editor's Note: Previous studies have extensively explored the impact of exercise on patients with early-stage cancer, but research on the effects of exercise in advanced cancer patients remains limited. The PREFERABLE-EFFECT study investigates how exercise influences the quality of life and fatigue in patients with metastatic breast cancer. Oncology Frontier invited Professor Anouk Hiensch, the principal investigator of the PREFERABLE-EFFECT study from the Julius Center at Utrecht University, to discuss the study's findings and their implications for patients.Oncology Frontier: Could you briefly introduce the background of the PREFERABLE-EFFECT study?
Professor Anouk Hiensch: Hi, I’m Anouk Hiensch. I work as an assistant professor at the Julius Center at the University Medical Center Utrecht, focusing on the effects of exercise on cancer patients. Over the past few decades, significant research in exercise oncology has led to the development of several guidelines, such as the ASCO and ACSM guidelines, which demonstrate that exercise benefits cardiorespiratory fitness, fatigue, and quality of life. However, this research primarily targets curable cancers. This is why further studies on metastatic breast cancer patients are crucial, and the PREFERABLE-EFFECT study addresses this gap. The primary aim of the PREFERABLE-EFFECT study was to investigate how exercise affects the quality of life and fatigue in patients with metastatic breast cancer.
Oncology Frontier: What are the results of the PREFERABLE-EFFECT study? What is the significance for breast cancer patients?
Professor Anouk Hiensch: In the PREFERABLE-EFFECT study, we randomized patients into either an exercise intervention group or a control group. The control group received standard care along with general physical activity advice, while the intervention group participated in a nine-month structured and individualized exercise program supervised by exercise professionals. We monitored several metrics, including patient-reported fatigue and quality of life, at baseline, three months, six months, and nine months. The results indicated that the exercise intervention positively impacted both the quality of life and physical fatigue, our primary endpoints. Patients in the intervention group reported higher quality of life and lower levels of fatigue compared to the control group. Additionally, we assessed other clinically relevant outcomes and found that the intervention group performed better in terms of pain, role functioning, physical functioning, and social functioning, allowing them to better engage in daily activities and social interactions. We then examined whether these effects were consistent across all patients in our study by analyzing subgroups. We discovered that patients under 50 years old experienced greater benefits from the exercise intervention on quality of life. While older patients (50 years and above) also benefited from exercise, the effects were not as pronounced as in younger patients. Furthermore, patients with higher baseline fatigue levels showed more significant improvements in quality of life following the exercise intervention. Based on these findings, we concluded that supervised exercise is beneficial for patients with metastatic breast cancer, enhancing their quality of life, reducing physical fatigue, and positively impacting other clinically relevant endpoints. Although our results were generally consistent across subgroups, we identified two important groups: patients reporting pain at baseline benefited more from the exercise intervention, and older patients (50 years and above) also benefited, but might require more tailored approaches to achieve similar benefits as younger patients.
Oncology Frontier: Do you think exercise can reduce fatigue in breast cancer patients, and should all patients with advanced breast cancer be physically active?
Professor Anouk Hiensch: Previous research has shown that exercise can improve fatigue in early-stage breast cancer patients. The PREFERABLE-EFFECT study also demonstrated that exercise benefits patients with metastatic breast cancer, enhancing their physical functioning. We observed that most patients could actively participate in exercise programs. In our study, 77% of patients attended exercise sessions over the nine-month period. The main reasons for non-attendance were holidays or being too ill or undergoing treatment, which are understandable over a nine-month span. Our exercise program was quite extensive and intensive, involving high-intensity interval training, and patients were able to perform these exercises. I believe we can effectively train patients to exercise at moderate to high intensities. However, we need to examine compliance and adapt the exercise program to match patients’ fitness levels as needed. This will be the focus of our future work.
