Fatigue, serum cytokine levels, and blood cell counts during radiotherapy of patients with breast cancer

Purpose: To assess the level of fatigue during the course of adjuvant radio therapy (RT) of breast cancer patients and its relation to anxiety, depress ion, serum cytokines, and blood count levels. Methods and Materials: Forty-one patients who received adjuvant RT after br east-conserving surgery were prospectively studied. All patients underwent RT without concomitant chemotherapy. Patients rated their fatigue with two standardized self-assessment instruments, the Fatigue Assessment Questionna ire and a visual analog scale on fatigue intensity, before RT, during weeks 1-5 of RT, and 2 months after RT completion. In addition, the anxiety and depression levels were assessed with the Hospital Anxiety and Depression Sc ale. A differential blood cell count and the serum levels of the cytokines interleukin (IL)-1 beta, IL-6, and tumor necrosis factor-alpha were determi ned in parallel to the fatigue assessments. Results: Fatigue intensity as assessed with the visual analog scale increas ed (p < 0.001) until treatment week 4 and remained elevated until week 5. T wo months after RT, the values had fallen to the pretreatment levels. Fatig ue measured xvith the Fatigue Assessment Questionnaire did not increase sig nificantly during treatment, but the subscores on physical (p = 0.035) and cognitive (p = 0.015) fatigue were elevated during treatment weeks 4 and 5. Affective fatigue did not change significantly. Anxiety, as rated with the Hospital Anxiety and Depression Scale, declined during RT (p = 0.002), but the Hospital Anxiety and Depression Scale depression score did not change significantly. IL-1 beta, IL-6, and tumor necrosis faetor-alpha levels did not change during therapy and did not correlate with fatigue. Peripheral bl ood cell levels declined significantly during therapy and were still low 2 months after treatment. Until treatment week 5, lymphocytes were reduced to almost 50% of their initial values. Hemoglobin levels did not correlate wi th fatigue. Conclusions: We observed an increase in fatigue during adjuvant RT of patie nts with breast cancer. Fatigue returned to pretreatment levels 2 months af ter treatment. No evidence was found that anxiety, depression, serum levels of IL-1 beta, EL-6, tumor necrosis factor-alpha, or declining hemoglobin l evels were responsible for the treatment-induced fatigue. (C) 2001 Elsevier Science Inc.