Health utility scores of colorectal cancer based on societal preference in Japan

Abstract

We measured health utility scores of colorectal cancer (CRC) patients from a societal perspective in Japan. Twenty-five states of health were described: four metastatic states without severe adverse events (AEs), 16 metastatic states with Grade 3/4 AEs, four adjuvant states, and one terminal state. A total of 1,500 respondents stratified by age and gender were recruited randomly from the largest Web-panel in Japan. Respondents were allocated randomly to three of the 25 health states and answered questionnaires by standard gamble (SG) and time trade-off (TTO) methods. Although utility scores of metastatic CRC receiving XELOX (capecitabine plus oxaliplatin) chemotherapy were 0.48(SG and TTO) (with stoma) and 0.57(SG) or 0.59(TTO) (without stoma), utility scores of those receiving FOLFOX4 (5-fluorouracil/folinic acid and oxaliplatin) chemotherapy were 0.42(SG) or 0.43(TTO) (with stoma) and 0.52(SG) or 0.53(TTO) (without stoma). These differences between XELOX and FOLFOX4 were statistically significant (P = 0.0198 in SG and P = 0.0059 in TTO). Stage 3/4 AEs decreased utility scores to 0.35-0.4 and 0.4-0.45 in the presence and absence of stoma, respectively. XELOX was generally considered a significantly preferable chemotherapy regimen compared to FOLFOX4 for CRC in Japan. Almost all Grade 3/4 AEs and stoma significantly decreased utility scores. These differences are dependent on the accuracy of the health state description and to confirm these results. In future research, it would be preferable that preference-based HRQoL measures are used directly in patients if utility scores are practically measurable by such method.