Characterisation of quality of life and late side-effects in breast cancer patients  

The observational REBECCA-CRF study (also called the REBECCA-1 study), conducted at Stavanger University Hospital (SUH) in Norway, aims to expand knowledge about the quality of life of patients affected by cancer-related fatigue (CRF) during and after cancer treatment.

CRF is one of the most common side effects of breast cancer treatment, often persisting for years after the completion of therapy in otherwise healthy cancer survivors. It is characterised by fatigue that is not relieved by sleep or rest. Patients with CRF experience physical, emotional, and mental exhaustion, leading to significant challenges in daily life. These challenges may include reduced physical and social activity, increased need for sleep, elevated stress levels, and limited participation in leisure activities compared to healthy individuals.

To better understand the challenges faced by breast cancer patients with CRF, the REBECCA study collects data from various sources using the REBECCA system, including:

  • Real-world data from Garmin smartwatches to monitor patients’ physical activity, sleep, and stress levels.
  • GPS location data from the REBECCA patient app to measure “life space,” or time spent outside the home engaging in leisure and social activities.
  • Quality of life data gathered through patient-reported outcome measures (PROMs), which are standardised questionnaires regarded as the gold standard in clinical studies today.

All breast cancer patients visiting SUH clinics between May 2022 and May 2023 were invited to participate in the study, regardless of their breast cancer type. Those who consented were recruited through the Department of Breast and Endocrine Surgery. During this period, 57 patients and 53 healthy control women were enrolled.

Patients are included at the time of diagnosis and receive the REBECCA system after completing primary treatment, with data collection continuing for 18 months. Healthy control women, however, receive the system upon inclusion and provide data for 12 months. Now in the fourth year of the project, 97% of healthy controls and 53% of patients have completed their participation, providing valuable data over the 12–18-month study period.

The data collected by the REBECCA system is analysed in relation to patients’ breast cancer diagnoses and treatments by the project’s technical partners. These analyses aim to identify relationships between the disease and lifestyle behaviours linked to CRF. The study will explore differences in quality of life among patients with severe fatigue, mild fatigue, and healthy controls.

Additionally, biological samples, including blood and stool, are collected to investigate biomarkers that could shed light on the underlying mechanisms of CRF, which remain largely unknown. These samples are analysed by the Department of Pathology.

Finally, we would like to extend our heartfelt gratitude to all participants in the REBECCA study for their invaluable contributions.