Docetaxel plus cyclophosphamide is cost-effective compared to doxorubicin plus cyclophosphamide, based on an economic analysis of US oncology trial 9735: additional rationale to avoid anthracyclines in the adjuvant treatment of operable breast cancer?.
Authors: S Verma, N Mittmann, L Bernard, M Thompson, B Chan, L Asmar, S Jones
Journal: Cancer Research (2009)

Abstract Abstract #6105 Background: Extended 7-year follow-up of the US Oncology Adjuvant Trial 9735 demonstrated that docetaxel plus cyclophosphamide (TC) as adjuvant treatment of operable invasive breast cancer significantly improves disease-free survival (DFS) and overall survival (OS) compared to doxorubicin plus cyclophosphamide (AC). DFS was 81% vs. 75%, respectively (p = 0.033) and OS was 87% vs. 82%, respectively (p = 0.032). A lifetime cost-effectiveness analysis of TC versus AC was conducted from a Canadian (province of Ontario) government payer perspective, based on head-to-head clinical data from Trial 9735. Methods: Survival and monthly risk of disease recurrence of women with early stage breast cancer (base case typifying those entered into the trial) was estimated up to 7 years using OS and DFS data from Trial 9735. Survival was extrapolated to lifetime using life expectancy estimates from the Canadian general population. Canadian resource utilization and unit costs were applied to estimate the costs of chemotherapy (including drug and administration costs), chemotherapy-related toxicities and disease recurrence. Quality of life (utility) weights for health states and events, used in the calculation of quality-adjusted life years (QALYs), were derived from the literature. Total costs, life years and QALYs were calculated for a lifetime horizon. Results: Life years and QALYs were higher for TC patients compared to AC patients, due primarily to longer survival and fewer recurrences for patients receiving TC. The predicted life expectancy of patients receiving TC and AC was 14.64 and 14.02 years, respectively. Mean total lifetime disease-related costs were $12,840 with TC and $8,579 with AC; the difference in costs was driven by higher drug acquisition costs for TC. Cost per life year gained (TC vs. AC) was $6,842 and cost per QALY gained was $8,251, discounting costs and outcomes at 5% per year. Base case results were most sensitive to assumptions regarding time horizon. In a sensitivity analysis conducted with a 7-year time horizon (the time frame of the clinical trial), cost per life year gained was $36,120 and cost per QALY gained was $43,248. In additional one-way sensitivity analyses conducted with a lifetime horizon and alternative assumptions regarding survival extrapolation, utility estimates, costs and discount rate, cost per life year gained remained between $2,982 and $7,538 and cost per QALY gained remained between $3,600 and $9,090. Conclusion: In patients with early stage, operable, invasive breast cancer, adjuvant treatment with TC provides gains in terms of life years and QALYs compared to AC and results in favourable cost-effectiveness ratios that should be acceptable in most jurisdictions. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6105.