EE50
A cost-consequence model of using the 21-gene breast ® Recurrence Score assay to identify patients with early-stage node-positive (N1) breast cancer who benefit from adjuvant chemotherapy in the Netherlands (SUPPLEMENT) Peter M. Machielsen a; Felix E. de Jongh b; Pieter B. Drost c; Martijn J.H.G. Simons d; Jelle A. Spoorendonk a,
d
Exact Sciences, the Netherlands; b, Ikazia Ziekenhuis Rotterdam, the Netherlands; c, Exact Sciences, Baar, Switzerland; d, OPEN Health Group, Rotterdam, the Netherlands
Table 1. Costs for ACT, treating AEs, productivity losses and GEP testing
INTRODUCTION • Early-stage (I, II, IIIa), hormone receptor positive (HR+), human epidermal growth factor receptor 2 negative (HER2-), 1-3 node positive (N1) breast cancer patients are often curatively treated with endocrine therapy (ET) and adjuvant chemotherapy (ACT) to reduce the chance of recurrences.
Cost category
Costs
Description
3 x FEC100 + 3xT
€5,016
Administered to 50% of the patient population.
4 x (dd)AC + 12xP (weekly)
€6,492
Administered to 25% of the patient population.
4 x (dd)AC + 4xT
€5,276
Administered to 25% of the patient population.
Acquisition costs ACT (average) 5
€5,450
An average cost for ACT acquisition was calculated based on the three most frequently administered treatment regimens in this patient population.
3 x FEC100 + 3xT
€4,200
Administered to 50% of the patient population.
4 x (dd)AC + 12xP (weekly)
€11,200
Administered to 25% of the patient population.
4 x (dd)AC + 4xT
€5,600
Administered to 25% of the patient population.
Administration costs ACT (average) 6
€6,300
An average cost for ACT administration was calculated based on the three most frequently administered treatment regimens in this patient population.
Short-term AEs grade I/II
€1,154*
• A validated cost-consequence model for node negative (N0) breast cancer patients2 was used as the basis to create the N1 model (Figure 1), which was revalidated by a clinical oncology expert specialized in breast cancer and by using external data.
Short-term AEs grade III
€2,071*
• The model compared the deterministic costs and consequences of two diagnostic strategies, ‘21-gene breast RS®’ and ‘no GEP testing’, and the subsequent ACT use.
Short-term AEs grade IV
€299*
Long-term AEs (AML)
€347
• Based on an incidence of 15,000 breast cancer patients, N=821 patients were eligible for the 21-gene breast RS® assay in the Netherlands (Figure 2).3,4
Long-term AEs (CHF)
€188
• In the ‘21-gene breast RS®’ strategy, patients were stratified into two risk groups based on RS®, with only the high-risk group receiving ACT (Figure 1). All patients in the ‘no GEP testing’ strategy were treated with ACT.
Productivity losses 18,19
• Each diagnostic strategy included costs for: acquisition and administration of ACT, treatment of adverse events (AEs), productivity losses, and GEP testing, according to RS® results (Table 1). Costs for ET and treating recurrences were not included as they were equal in both testing strategies.
GEP testing
• However, not all women, e.g., post-menopausal women, benefit from ACT and can be overtreated leading to considerable humanistic and economic burden.1 • Randomised controlled studies have demonstrated that the 21-gene Breast Recurrence Score (RS)® assay can identify patients at higher risk for disease recurrence and predict the benefit of ACT.1 • The budgetary consequence of using the 21-gene breast RS® assay versus no gene expression profiling (GEP) testing for N1 patients in the Netherlands is currently unknown.
OBJECTIVE RS®
• To assess the expected budgetary consequences of introducing the 21-gene breast assay, to identify patients with a high-risk RS® result who will benefit from ACT in postmenopausal women with early-stage, HR+, HER2-, N1 invasive breast cancer, in the Dutch clinical practice.
METHODS
• The model’s time horizon was 5 years, a societal Dutch healthcare perspective was adopted, and the data was derived from the literature. • Costs were calculated per cost category, as total for the entire population and per patient, for each diagnostic strategy.
20
No GEP testing
Neutropenia, fatigue, dyspnoea and skin rashes amongst others. The probability of patients experiencing these AEs was multiplied with the costs for treating them.9-17 AML & CHF. The 5-yeas probability of patients experiencing these AEs was multiplied with the costs for treating them.
€3,638
The friction method was used. Assumptions: average sick leave of 24 weeks, post-menopausal women worked until 65 year, and for 20 hours a week on average.
€4,594
Cost for using the 21-gene breast RS assay as a diagnostic test.
€0
There were no testing costs in the no GEP testing strategy.
*, Weighted average of the cost for treating multiple AEs based on the probability of occurrence. 3xFEC100+3xT, three cycles of fluorouracil-epirubicin-cyclophosphamide followed by three cycles of docetaxel. 4x(dd)AC+12xP(weekly), four cycles of doxorubicin-cyclophosphamide followed by twelve cycles of paclitaxel. 4x(dd)AC+4xT, four cycles of doxorubicin-cyclophosphamide followed by four cycles of docetaxel. ACT, adjuvant chemotherapy; AEs, adverse events; AML, Acute myeloid leukaemia; CHF, chronic heart failure; GEP, gene expression profiling; RS, recurrence score.
Figure 1. Structural overview of the cost-consequence model
Costs for ACT are calculated over a period of 6 months. ACT, Adjuvant Chemotherapy; GEP, gene expression profiling; HER2-, Human epidermal growth factor receptor 2 negative; HR+, Hormone receptor positive; N1, Nodal stage (1 to 3 positive lymph nodes); RS, Recurrence score.
Figure 2. Model population, eligible for 21-gene breast RS® Total population of patients with early-stage invasive breast cancer in the Netherlands (n=15,000)
Early-stage invasive breast cancer patients with stage I, II, IIIa disease (n=11,250)
Stage I, II, IIIa breast cancer patients who are HR+ and HER2- (n=8,269)
HR+, HER2-, stage I, II, IIIa breast cancer patients with 1-3 positive lymph nodes (N1) (n=1,216)
Post-menopausal women with early-stage, HR+, HER2-, N1 invasive breast cancer (n=821) HER2-, Human epidermal growth factor receptor 2 negative; HR+, Hormone receptor positive; N1, Nodal stage (1 to 3 positive lymph nodes).
ISPOR Europe 2022 - Vienna
EXS13789_1022_NL_NL