Cost-effectiveness and resource use of implementing MRI-guided NACT in ER-positive/HER2-negative breast cancers in The Netherlands

Table 2 Definitions of true-favourable, false-favourable, true-unfavourable and false-unfavourable used in our study

Group of patients	Definition
True favourable	Patient that is classified as favourable at monitoring (criteria [7]), continues receiving NACT 1, and after 5 years of follow up is classified as favourable due to absence of relapse event
False favourable	Patient that is classified as favourable at monitoring (criteria [7]), continues receiving NACT 1, and after 5 years of follow up is classified as unfavourable due to presence of relapse event
True unfavourable	Patient that is unfavourable at monitoring (criteria [7]), switches to NACT 2, and after 5 years of follow up is classified as favourable due to absence of relapse event (the underlying assumption is that the patient was not responding to NACT1 but did to NACT 2, thereby demonstrating that monitoring classified the patient properly)
False unfavourable	Patient that is unfavourable at monitoring (criteria [7]), switches to NACT 2, and after 5 years of follow up is classified as unfavourable due to presence of relapse event (the underlying assumption is that the patient was responding to NACT1 and did not to NACT 2, thereby demonstrating that monitoring classified the patient wrongly) ^a

^aAlthough we are aware that in the ‘False favourable’ group there could be patients irresponsive to both NACT 1 and 2, as the design of the RG-NACT does not allow distinguishing them, we had to make such an assumption

ISSN: 1471-2407