Fatigue Experience in Oncology; a Targeted Qualitative Literature Review and Novel Patient-Centric Conceptual Model

Traditionally, treatment endpoints in oncology have focused on increasing overall survival and progression-free survival. Although fatigue may be a meaningful outcome measure across different cancers, it is assessed less frequently. To explore the impact of fatigue on patients with cancer, confirm the importance of fatigue measurement and inform future measurement strategies in oncology, we aimed to characterise the patient experience of fatigue and the associated impact on how patients feel and function, including aspects of health-related quality of life (HRQoL).

A targeted literature review of published fatigue-related qualitative publications in oncology was conducted in MEDLINE, Embase and PsycINFO, limited to studies published between 2018 and 2023. Concepts were extracted from the qualitative literature and patient quotes or author descriptions/interpretations were subject to secondary analysis using semantic, qualitative, directed content analysis techniques via ATLAS.ti v9. The literature review informed the development of a preliminary patient-centric conceptual model of fatigue in oncology.

Of 1210 identified publications, 26 were selected for data extraction, including 512 patients living with 28 different oncology indications across geographies. Frequently reported fatigue triggers included treatments and cancer itself. Patients used various fatigue descriptors, including low/lack/loss of energy, tiredness and exhaustion, across disease stages. Physiological and cognitive manifestations of fatigue were reported, and fatigue episodes were described as unpredictable and of variable severity, duration and frequency. Cancer-related fatigue had a substantial negative effect on patients' QoL, including emotional, physical, physiological, social, activities of daily living, sleep and work impacts. Unmet needs included poor support from healthcare professionals (HCPs).

This review demonstrated that fatigue is an impactful symptom across oncology indications and provides the first holistic conceptual model of cancer-related fatigue across disease stages and treatments. Future research should review clinical outcome assessments (COA) that may be fit-for-purpose for measuring fatigue in oncology clinical trials.