Table 1 Scenario results and likelihoods derived from the workshop with experts

1

Hesitant adopters (100% likely)

Professionals, who are not using the 70-gene signature until the results of the MINDACT are released, will delay the diffusion (spreading of the signature) process. This will be expressed in the proportion of non-compliance towards the signature result.

2

User-friendliness (90% likely)

There is a mix of new functions possible on the (read-out) microarray; such as ER/PgR/Her2 status, singles genes, with new possibilities for e.g. targeted therapies. Furthermore, by using needle biopsies the application becomes more user-friendly. This will be expressed in a decrease of failures of the signature.

3

Progressive techniques (90% likely)

There is positive proof for the value of RNA-preservation instead of formalin-based tissue for future research, which causes an increased use of the 70-gene signature. This will be expressed in a decrease of failures of the signature.

4

Progressive uptake (90% likely)

The 70-gene signature has developed further and can be used safely for all node negative and 1–3 positive patients. The uptake is 100% in your county and is embedded in the national guidelines. This will be expressed in an increasing number of patients receiving signature.

5

Financial access (75% likely)

The insurance companies in the Netherlands don’t reimburse the use of the 70-gene signature yet (2008). If the insurers were to reimburse the 70-gene signature, the rate of reimbursement agreements would be rather more progressive throughout Europe. This will be expressed in a –slightly slow- increase of patients receiving the signature.

6

Other paraffin/test (60% likely)

Another PRC-based, user-friendly test appears on the market, and the market share of the 70-gene signature decreases.

7

Competitive test (60% likely)

The Oncotype DX ‘wins’ the competition; the market share of the 70-gene signature decreases.

8

Era after: CTC? (40% likely)

A totally new (nano) technology has been developed (using fresh frozen tumour samples) which has more value than the 70-gene signature and - due to this test - the market share of the 70-gene signature decreases.

9

Provision on free market (18% likely)

Besides being used in the MINDACT trial, 70-gene signature is also available on the free market, to prevent unethical situations due to patient selection.

10

Regulation/legislation barrier (5% likely)

There is a probability of legal regulation by way of FDA clearance. Because the 70-gene signature has FDA and IVDMIA (In Vitro Diagnostic Multivariate Index Assay) approval, the market share of the Oncotype DX decreases.