OBJECTIVES: Adjuvant treatment options for women with primary breast cancer include hormone therapy alone, or adjuvant chemotherapy prior to hormone therapy. Gene expression profiling tests are increasingly being to improve targeting of treatments. The cost-effectiveness of one such test, Prosigna®, was explored in the Australian setting.

METHODS: A cost-utility analysis was conducted. The structure of the model was consistent with previously published models of gene expression profiling tests and comprised of two parts. The first, a decision-analytic, assigned treatments to patients according to their risk of distant recurrence; then, a Markov process determined the probability of experiencing a distant recurrence and estimated the costs and quality-adjusted life years (QALYs) over a 30-year time horizon to produce an incremental cost-effectiveness ratio (ICER) per QALY gained. Clinical inputs were informed by a systematic literature review of the effectiveness and safety of Prosigna. Modelled costs included those associated with the test, adjuvant treatment, monitoring and the cost of treating distant recurrences. Utility weights from the literature were used; these varied by model health state and by treatment received.

RESULTS: Prosigna was associated with an ICER of AUD $43,031 per QALY gained. The incremental costs were predominantly driven by the cost of the test, with offsets due to a reduction in adjuvant chemotherapy use and a reduction in the costs of treating distant recurrence. Sensitivity analyses were conducted and found that the ICER was most sensitive to the selection of the time horizon, the modelled treatment effect for the addition of chemotherapy (stratified by risk of recurrence) and the disutility of chemotherapy applied.

CONCLUSIONS: Prosigna appears likely to be cost-effective for certain populations in the Australian setting, however conclusions are limited due to the underlying uncertainty with the applicability of the clinical inputs used.