Abstract OT3-13-01: Estimation of willingness-to-pay for breast cancer treatments through contingent valuation method in Japanese breast cancer patients (JCOG1709A)
Authors: Iwatani Tsuguo , Hara Fumikata , Iwata Hiroji , Shien Tadahiko , Hojo Takashi , Sagara Yasuaki , Masuda Norikazu , Takahashi Masato , Saji Shigehira , Fujisawa Tomomi , Kondo Naoto , Shimomura Akihiko 
Published: March 2020

Background: Medical expenses are on an increasing trend due to "medical innovation". The Japanese government introduced health technology assessment (HTA) in April 2016. HTA is the systematic evaluation process of scientific value, economic, social and ethical issues related to medical technology with fair and robust methods while ensuring transparency. Two achievements are expected in our research. First, we establish the evaluation standard for the interpretation of the results of cost-effectiveness analysis (CEA) of clinical trials for a standard treatment for breast cancer. Next, we can re-evaluate the HTA's decision making based on the viewpoint of general Japanese population from the perspective of cancer patients. We believe this research can contribute to the creation of a healthcare system that is meaningful to patients, clinicians, industries, and healthcare policymakers. Specific Aims: The aim of this study is to prove how Japanese breast cancer patients who received treatment in Japan consider the financial value (willingness to pay; WTP) for their life and health by using the Contingent Valuation Method (CVM), prospectively. Based on our results, we will construct an evaluation axis from patients’ viewpoint for the cost effectiveness of clinical trials to establish standard treatments for breast cancer. Key Eligibility Criteria: For Japanese breast cancer patients aged 20 to 79 who meet the followings. Unilateral breast cancer patients who fulfill either i) or ii) below i) Primary breast cancer of clinical stage 0 through III for which surgery and/ or chemotherapy and / or radiotherapy has been completed as initial treatment and that is currently undergoing regular follow-up observations or postoperative endocrine therapy. ii) Undergoing endocrine therapy or first-line through third-line chemotherapy for metastatic or recurrent cancer at least 2 months. Trial Design: This study will be conducted by the Breast Cancer Study Group of the Japan Clinical Oncology Group (JCOG). We will investigate WTP for hypothetical scenarios for primary breast cancer patients (PBC) and metastatic breast cancer patients (MBC), using a two-step dichotomous-choice method in CVM. For PBC, we will evaluate the monetary value of the prevention of recurrent cancer. Therefore, to investigate WTP, we will present hypothetical new treatments for preventing breast cancer death to these patients. In MBC, new treatments for extending survival time is presented as hypothetical scenarios and the patients’ WTP is investigated. Statistical Methods: Questionnaire data that is returned by 4 weeks (postmark deadline) after enrollment is completed at the facility and will be considered valid and analyzed. While the WTP amounts of individual responders are not clarified with the two-step dichotomous-choice method, analyses will proceed considering the obtained responses as follows. With the two-step dichotomous-choice method, if the first stage response is yes, a higher amount will be displayed for the second stage. If the first stage response is no, a lower amount will be shown for the second stage. Target Accrual: The study will be conducted in two stages. First, 168 patients (84 patients with PBC and 84 patients with MBC) will be examined to determine their WTP for setting up the dichotomous-choice method survey form. Next, 1,596 patients (798 patients with PBC and 798 patients with MBC) will be surveyed on their WTP for hypothetical scenarios in CVM. Approximately 1800 patients with primary breast cancer and stable metastatic breast cancer are enrolled. Contact information for people with a specific interest in the trial: Tsuguo Iwatani, MD, PhD. Department of Breast Surgery, National Cancer Center Hospital East tiwatani@east.ncc.go.jp

Citation Format: Tsuguo Iwatani, Fumikata Hara, Hiroji Iwata, Tadahiko Shien, Takashi Hojo, Yasuaki Sagara, Norikazu Masuda, Masato Takahashi, Shigehira Saji, Tomomi Fujisawa, Naoto Kondo, Akihiko Shimomura. Estimation of willingness-to-pay for breast cancer treatments through contingent valuation method in Japanese breast cancer patients (JCOG1709A) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT3-13-01.