Purpose: The aim of this study was to evaluate fatigue 2.5 years after adjuvant radiation therapy (RT) in patients with localized breast cancer and to assess its relation to pre- and immediate post-treatment fatigue values. The association of fatigue with psychological distress and functional impairment was analyzed as well as pretreatment predictors for chronic fatigue.
Methods: Of a set of 41 patients whose fatigue was evaluated during adjuvant radiation therapy, 38 patients alive and free of cancer at 2.5 years (t2) after RT were assessed in this study. Patients received the Fatigue Assessment Questionnaire (FAQ), a visual analog scale on fatigue intensity (VAS-F) as well as on cancer-related distress (VAS-D), the Hospital Anxiety and Depression Scale (HADS), and three questions of the Short-Form 36-Item Health Survey (SF-36) per mail. All 38 patients returned their questionnaires. The values were compared to pretreatment (t0) and immediate post-treatment levels (2 months after RT, t1).
Results: There was no significant difference between chronic fatigue levels at 2.5 years after RT and pretreatment values. When compared to immediate post-treatment levels the FAQ global score and the HADS anxiety score displayed a significant increase. Cancer-related distress correlated closely with fatigue scores. Patients with functional impairment had slightly higher fatigue values. Age or hormonal therapy were not associated with chronic fatigue levels. Pretreatment fatigue and pretreatment HADS anxiety and depression scores were good predictors of fatigue at 2.5 years after RT explaining 60% (FAQ) and 49% (VAS-F) of its variance.
Conclusions: Fatigue 2.5 years after RT did not increase above baseline levels before RT in conservatively operated breast cancer patients. Chronic fatigue correlated closely with psychological distress. Patients with pretreatment elevated fatigue, anxiety or depression levels are at risk for chronic fatigue.