HEALTH-RELATED QUALITY OF LIFE IN JAPANESE PATIENTS WITH BLADDER CANCER ACCORDING TO A NEWLY DEVELOPED JAPANESE VERSION OF THE BLADDER CANCER INDEX

427 Background: We developed a Japanese version of the Bladder Cancer Index (BCI) to measure HRQOL in Japanese patients treated with various surgical methods. In addition, we performed a cross-cultural comparison of sexual function and bother in bladder cancer patients between the United States and Japan. Methods: The Japanese version of the BCI was developed through a multistage process after a pilot study. Its reliability and validity were examined in Japanese bladder cancer patients via a cross-sectional analysis. The patients were enrolled from August 2016 to March 2018. They also completed the Japanese version of Short Form (SF)-12, the EuroQol five-dimension scale (EQ-5D), and the Functional Assessment of Cancer Therapy-Bladder (FACT-BL). We also compared the Japanese cohort with an American cohort; i.e., the validation cohort used to develop the original version of the English BCI. Results: In total, 371 patients with a median age of 72 years and a median disease duration of 29 months were enrolled. Of these patients, 221 underwent transurethral resection of the bladder tumor, and 150 underwent radical cystectomy. The internal consistency value was ≥0.7 for all subscales, except the bowel function subscale. Each BCI domain was poorly correlated with the SF-12 and EQ-5D, but moderately well correlated with the FACT-BL. The urinary function and bowel function scales exhibited minimal (2.1–9.7%) amounts of missing data, whereas relatively high (≥15%) levels of missing data were seen in items relating to urinary bother, bowel bother, sexual function, or sexual bother. A missing data value of ≥15% was correlated with higher age (p<0.05). Japanese patients were more likely than American patients to report poor sexual function. However, Japanese were less likely than American to be concerned about sexual function. Conclusions: We confirmed the reliability and validity of the Japanese version of the BCI, although it needs to be revised to make it more comprehensible for elderly patients. We found differences between American and Japanese patients with bladder cancer. The BCI can be used for cross-cultural assessments of HRQOL in bladder cancer patients.