Patient preferences for treatment of castration-resistant prostate cancer in Japan: a discrete-choice experiment.
BACKGROUND
Up to a fifth of patients diagnosed with prostate cancer (PC) will develop castration-resistant prostate cancer (CRPC), which has been associated with a poor prognosis. The aim of this study was to consider the patient perspective as part of the overall treatment decision-making process for CRPC, given that an alignment between patient preference and prescribing has been shown to benefit patient outcomes. This study examines preferences of patients with CRPC in Japan for treatment features associated with treatments like RA-223, abiraterone, and docetaxel and to examine the extent to which treatment preferences may vary between symptomatic and asymptomatic patients.


METHODS
A two-phase research approach was implemented. In Phase 1, N = 8 patients with CRPC were recruited from a single hospital to complete a qualitative interview to provide feedback on the draft survey. In Phase 2, N = 134 patients with CRPC were recruited from five hospitals to complete a paper survey. The survey included 6 treatment choice questions, each asking patients to choose between two hypothetical treatments for their CRPC. Each treatment alternative was defined by the following attributes: length of overall survival (OS), time to a symptomatic skeletal event (SSE), method of administration, reduction in the risk of bone pain, treatment-associated risk of fatigue and lost work days. A hierarchical Bayesian logistic regression was used to estimate relative preference weights for each attribute level and mean relative importance.


RESULTS
A total of N = 133 patients with CRPC completed the survey and were included in the final analysis. Patients had a mean age of 75.4 years (SD = 7.4) and had been diagnosed with PC a mean of 6.5 years prior (SD = 4.4). Over the attribute levels shown, fatigue (relative importance [RI] = 24.9 %, 95 % CI: 24.7 %, 25.1 %) was the most important attribute, followed by reduction in the risk of bone pain (RI = 23.2 %, 95 % CI: 23.0 %, 23.5 %), and OS (RI = 19.2 %, 95 % CI: 19.0 %, 19.4 %). Although symptomatic patients placed significantly more importance on delaying an SSE (p < .05), no other preference differences were observed.


CONCLUSIONS
CRPC patients were more concerned about reduced quality of life from side effects of treatment rather than extension of survival, which may have implications for shared decision-making between patients and physicians.
Department of Urology and Renal Transplantation, Yokohama City University Medical Center, Yokohama, Japan.
Hiroji
H
Uemura
Division of Breast and Medical Oncology, National Cancer Center Hospital East, Chiba, Japan.
Nobuaki
N
Matsubara
Department of Urology, Nippon Medical School, Tokyo, Japan.
Go
G
Kimura
Division of Urology, Harasanshin General Hospital, Fukuoka, Japan.
Akito
A
Yamaguchi
Bayer Yakuhin, Ltd., 2-4-9, Umeda, Kita-ku, Osaka, 530-0001, Japan.
Dianne Athene
DA
Ledesma
Kantar Health, New York, NY, USA.
Marco
M
DiBonaventura
Bayer Healthcare, Whippany, NJ, USA.
Ateesha F
AF
Mohamed
Kantar Health, New York, NY, USA.
Enrique
E
Basurto
Kantar Health, New York, NY, USA.
Ian
I
McKinnon
Bayer Healthcare, Whippany, NJ, USA.
Ed
E
Wang
Kantar Health, New York, NY, USA.
Kristen
K
Concialdi
Bayer Yakuhin, Ltd., 2-4-9, Umeda, Kita-ku, Osaka, 530-0001, Japan.
Aya
A
Narimatsu
Bayer Yakuhin, Ltd., 2-4-9, Umeda, Kita-ku, Osaka, 530-0001, Japan. yasuko.aitoku@bayer.com.
Yasuko
Y
Aitoku
D000368:Aged; D000736:Androstenes / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000077143:Docetaxel; D006801:Humans; D007564:Japan; D008297:Male; D057240:Patient Preference; D064129:Prostatic Neoplasms, Castration-Resistant / Q000188:drug therapy* / Q000532:radiotherapy*; D011868:Radioisotopes / Q000627:therapeutic use*; D011883:Radium / Q000627:therapeutic use*; D043823:Taxoids / Q000627:therapeutic use*
D000736:Androstenes; D000970:Antineoplastic Agents; D011868:Radioisotopes; D043823:Taxoids; D000077143:Docetaxel; C089740:abiraterone; D011883:Radium
Bone pain; Castration-resistant prostate cancer; Fatigue; Patient preferences; Symptomatic