Cancer-related fatigue is one of the most prevalent symptoms in cancer survivors. Although fatigue is almost universal during active cancer treatment, persistent fatigue is described for over 10 years after treatment completion among long-term survivors. Cancer-related fatigue can result in substantial adverse physical, psychosocial, and socioeconomic consequences, having a negative impact on overall quality of life. However, fatigue is often underreported and not adequately managed proactively. Although no current gold standard treatment is available, evidence-based supportive care strategies for fatigue include physical exercise and psychosocial interventions; however, the implementation of these guideline-concordant options is often suboptimal.

Despite an improved understanding of the prevalence and course of cancer-related fatigue and some of its underlying biological mechanisms, including the role of cancer-related inflammation, most of the interindividual variability of this complex syndrome remains unexplained. To advance understanding and management of cancer-related fatigue, key questions that future research should address include improving early interception of risk of fatigue and providing tailored, risk stratified management strategies that can facilitate prevention of symptomatic deterioration. To address these questions, longitudinal studies are required that combine an adequate fatigue assessment along with comprehensive evaluations of risk factors. Particularly, innovative studies are warranted leveraging novel analytic methodologies (e.g., machine learning algorithms) that delve into multiple data dimensions, including clinical, behavioral, and biological risk factors (e.g., contribution of genetic polymorphisms or serum markers of inflammation, agnostic exploration of noninflammatory pathways, novel dimensions such as data from wearables and biosensors). The co-occurrence with fatigue of other cancer-related symptoms including emotional distress, insomnia, and cognitive dysfunction should also be explored. Interventional studies should then build on refined knowledge of modifiable risk factors and mechanisms and aim at personalizing care pathways to facilitate the uptake of tailored interventions to reduce or prevent fatigue.

This Special Issue aims to highlight research work performed to advance the knowledge of cancer-related fatigue and improve symptom management/prevention, with the general ambition of contributing to inform personalized, predictive, and preventive cancer survivorship care. Research areas may include (but are not limited to) quantitative observational research, particularly if focused on biological mechanisms and risk factors and novel methodologies, and interventional research focused on nonpharmacological and pharmacological approaches for cancer-related fatigue and related symptoms. Original research and review articles highlighting direct patient insight and involvement, including co-design studies are welcome. Research works highlighting interdisciplinary and transdisciplinary approaches spanning from oncology to computational science, methodology, and social and human sciences (eg, psychology, sociology) are strongly encouraged.

Potential topics include but are not limited to the following:

• Prevalence, course, and longitudinal trajectories of fatigue among cancer survivors
• Multidimensional aspects of cancer-related fatigue, including highlighting the physical, emotional, and cognitive dimension of fatigue
• Fatigue and co-occurring cancer-related symptoms: anxiety, depression, insomnia, and cognitive dysfunction
• Mechanisms of cancer-related fatigue
• Risk factors for cancer-related fatigue, particularly focusing on modifiable interventional targets
• Unimodal and multimodal predictive models of fatigue, including novel analytic and statistical approaches
• Patient and provider perspectives on communicating and proactively managing the risk of fatigue and related symptoms
• Management approaches for cancer-related fatigue: nonpharmacological and pharmacological interventions
• Qualitative studies providing insight into patient experience and attitudes about interventions focused on cancer-related fatigue