Multidimensional fatigue and its impact on work productivity, mood and quality of life in long-term survivors following definitive intensity-modulated radiotherapy for oropharyngeal cancer: A cross-sectional study.

Purpose: Radiotherapy (RT) for oropharyngeal cancer (OPC) can lead to late toxicity. Fatigue is a known debilitating issue for many cancer survivors, yet prevalence and severity of long-term fatigue in patients treated for OPC is unknown.

Method: As part of a mixed-methods study, fatigue in OPC patients ≥ 2 years post RT + / - chemotherapy was evaluated. Fatigue scores (multidimensional fatigue inventory; MFI) were compared to general population controls. Predictive sociodemographic/clinical factors of fatigue were investigated by multivariable linear regression. Associations between fatigue, health related quality of life (EQ-5D-5L), work (work productivity and activity impairment - WPAI), mood disturbance (Profile of Mood Scale - POMS) and RT dose were explored.

Results: In 349 patients treated for OPC with median follow-up time post-RT (+ / - chemo) of 6 years (IQR 4-8), > 20% reported severe fatigue in all domains. Scores were significantly worse in patients for mental (mean difference 1.2, 95% CI 0.6-1.8, p = < 0.001) and general fatigue (mean difference 0.8, 95% CI 0.1-1.3, p = 0.015) compared to controls. Age and co-morbidities were significant predictors of mental and general fatigue (p < 0.05). Worse fatigue was associated with worse quality of life, greater work productivity impairment and worse mood (r = - 0.604, 0.582 and 0.679, respectively, all p < 0.05). No correlation was found between fatigue and RT dose to the posterior fossa.

Conclusions: Mental and general fatigue remain significant issues in OPC patients several years after RT + / - chemotherapy.

Implications for cancer survivors: Better monitoring of fatigue throughout follow-up care, and timely interventions could help improve patient functioning.