A European cross-cultural analysis of worsening of functional scales in prostate cancer patients after RT

Abstract

Purpose or Objective The study aimed to evaluate the deterioration of functional outcomes in localized prostate cancer (PCa) patients (pts) treated with external beam radiotherapy (RT), including analysis of differences possibly due to cultural effects. Materials and Methods EORTC QLQ-C30 (version 3.0) was administered to pts enrolled in a multicenter prospective observational study in 7 European countries (UK, BE, NH, DE, IT, ES, FR). For this analysis, we specifically considered one symptom scale (Fatigue) and three functional scales (Physical, Role, Social) at three time-points: baseline, RT end and 2-year after RT. The average score variation in acute and late phases as stratified by country was determined. We used radar plots to report results quantitatively, and we computed the hexagonal areas from these plots to obtain a summary variable describing the functional status. Worsening in at least 2 (wrs2) or 3 (wrs3) scales were considered as further endpoints, with cut-offs for clinically significant deterioration defined as suggested by Cooks et al. (EJC 2012). Results A total of 1143 pts with complete information were available. Figure 1 shows radar plots with scores for the different scales. Physical functioning is the only scale that deteriorates at each time point (ageing effect?) in every country. Table 1 reports scores, hexagonal areas and the prevalence of wrs2/wrs3 as a function of country and time-points. The ratio of hexagonal areas “(at RT end)/(at 2-year)” is reported as an index for recovery of acute effects. Spanish Ratio (<1) shows a continuous deterioration with time. Wrs 2 and wrs3 at the end of RT were found in 31% (range 13% in ES – 45% in NH) and 16% (range 6% in ES – 23% in NH) of pts, respectively. Prevalence of wrs2 at 2 years was 23% (range 15% in IT – 28% in BE and NH), while wrs3 was 12% (range 11% in IT – 16% in NH). Conclusion Results from the EORTC QLQ-C30 highlighted a large variability across countries in the deterioration of functional scales at the end of RT (acute/early phase), with differences highly reduced at 2 years (late phase). Of note, there is a consequential effect in the deterioration of functional scales, with about two-thirds of patients with deterioration at RT end who did not recover after 2 years.