Purpose: To prospectively evaluate radiation-induced fatigue among patients undergoing curative radiotherapy at the Toronto Sunnybrook Regional Cancer Centre using two different instruments.
Materials and methods: Consecutive consenting English speaking men receiving curative radiotherapy for localised prostate cancer were enrolled in a prospective ethics board approved study. We used an 11 questions fatigue questionnaire (FQ) based on a modified FACT-AN questionnaire and the 2 questions of the fatigue pictogram (FP) to record patients' responses weekly during treatment. The 11 FQ items were summed to calculate a fatigue scale (FS). The proportion and 95% confidence interval for each FQ and FP item and mean FS was calculated at baseline, week 3 and week 6. Chi-squared tests or analysis of variance f-tests were used to compare treatment groups and paired t-tests to compare baseline to week 6. A linear mixed model was used to compare the mean FS for treatment groups across time.
Results: From June 2000 to June 2003, we enrolled 130 patients. Fifty-one received conformal radiotherapy to the prostate (CRT), 46 received whole pelvis and prostate boost radiotherapy (WP+PB) and 33 received post prostatectomy radiotherapy to the prostate bed (PBRT). At baseline, 39% (30-47%) reported some fatigue for the FQ and 60% (52-68%) for the FP tiredness item. As treatment progressed, the mean fatigue increased significantly. The FP tiredness item best differentiated between treatment groups (p = 0.04 at week 6) compared to the FQ tiredness item or FS. Those receiving irradiation to smaller volumes (CRT or PBRT) reported lower FS scores than those treated to larger volumes (WP+PB) across time.
Conclusions: The pictogram was better than the questionnaire in differentiating between treatment groups. The pictogram could be used to screen and monitor patients with baseline fatigue for interventional studies in a busy clinic.