Economic evaluation of chemoprevention of breast cancer with tamoxifen and raloxifene among high-risk women in Japan

Abstract

Raloxifene was approved for chemoprevention against breast cancer among high-risk women in addition to tamoxifen by the US Food and Drug Administration. This study aims to evaluate cost-effectiveness of these agents under Japan's health system. A costeffectiveness analysis with Markov model consisting of eight health states such as healthy, invasive breast cancer, and endometrial cancer is carried out. The model incorporated the findings of National Surgical Adjuvant Breast and Bowel Project P-1 and P-2 trial, and key costs obtained from health insurance claim reviews. Favourable results, that is cost saving or cost-effective, are found by both tamoxifen and raloxifene for the introduction of chemoprevention among extremely high-risk women such as having a history of atypical hyperplasia, a history of lobular carcinoma in situ or a 5-year predicted breast cancer risk of X5.01% starting at younger age, whereas unfavourable results, that is 'cost more and gain less' or cost-ineffective, are found for women with a 5-year predicted breast cancer risk of p5.00%. Therapeutic policy switch from tamoxifen to raloxifene among postmenopausal women are implied costeffective. Findings suggest that introduction of chemoprevention targeting extremely high-risk women in Japan can be justifiable as an efficient use of finite health-care resources, possibly contributing to cost containment.

Economic evaluation of the 70-gene prognosis-signature (MammaPrint®) in hormone receptor-positive, lymph node-negative, human epidermal growth factor receptor type 2-negative early stage breast cancer in Japan

“…For minor toxicity, from which 60% of patients suffer, the cost is included in the cost of adjuvant chemotherapy, since prophylactic use of antiemetic, for example, is routinely applied these days. And the clinical course of fatal toxicity is so diverse and not fit to costing by the modelling here, therefore, its cost is assumed to be the same as the end-of-life treatments cited from the literature [12,13,27].…”

“…The cost of the end-of-life treatments are ¥1,315,143/ year (US$14,613/year) [12,13,27], which is also used as the cost of treating fatal toxicity. Costs are also discounted at a rate of 3% [23].…”

Economic evaluation of the 21-gene signature (Oncotype DX®) in lymph node-negative/positive, hormone receptor-positive early-stage breast cancer based on Japanese validation study (JBCRG-TR03)

“…For minor toxicity, from which 60% of patients suffer, the cost is included in the cost of adjuvant chemotherapy, since prophylactic use of antiemetic, for example, is routinely applied these days. And the clinical course of fatal toxicity is so diverse and not fit to costing by modelling here, therefore, its cost is assumed to be the same as the end-of-life treatments cited from the literature [31].…”

“…The cost of the end-of-life treatments are ¥1,315,143 (US$13,151) per year [15,31], which is also used as the cost of treating fatal toxicity.…”

Cost‐effectiveness of chemoprevention of breast cancer using tamoxifen in a postmenopausal US population

“…Several cost‐effectiveness analyses have attempted to identify specific populations who would derive the most benefit from tamoxifen treatment, generally targeting women at elevated 5‐year Gail model breast cancer risk5 to balance the benefits of treatment with the potential harms of adverse events (AEs). Those studies determined that, although tamoxifen treatment unequivocally reduces breast cancer incidence, widespread use of tamoxifen is not cost‐effective because of its side‐effect profile, cost, and sensitivity to assumptions related to quality‐adjusted life year (QALY) utilities 6‐9. Those studies used side‐effect relative risks derived from the NSABP clinical trial and assumed that breast cancer risk reduction was limited to the duration of active treatment (typically, 5 years).…”