Prospective evaluation of fatigue during a course of curative radiotherapy for localised prostate cancer

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. Conclusion 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.