189P - Enhancing decision-making about adjuvant chemotherapy in ER+, HER2- early breast cancer (EBC) following EndoPredict testing

Abstract

Background: Chemotherapy side-effects can be substantial. There is increasing recognition that with surgery, radiotherapy and hormone treatment (tmt), many patients (pts) derive no benefit from chemotherapy and experience only iatrogenic harm. Gene expression profiling tests can help refine recurrence risk and likely chemotherapy benefit. EndoPredict is a multigene test which includes clinico-pathologic parameters to produce an EPclin score classifying risks of distant recurrence as low or high for ER+ve HER2–ve pts treated with adjuvant endocrine tmt alone. We compared tmt decisions pre and post EndoPredict test results, pts’ anxiety, decisional conflict and oncologists’ confidence about decisions made. Methods: 14 oncologists in 7 UK hospitals saw 149 pts judged to have equivocal indications for chemotherapy. Pts and oncologists discussed provisional tmt decisions based on usual prognostic factors. These decisions were reconsidered when EPclin results were available. Pre and post-test pts completed Spielberger’s State/Trait Anxiety inventory (STAI) and a decision conflict scale (DCS). Oncologists additionally recorded:- basic clinical details, their agreement with, and confidence about tmt decisions (endocrine (E) therapy +/- chemotherapy(C)). Results: 66.7% pts with an initial E alone decision and a high risk result upgraded to E+C. 9.4% pts with initial E+C decisions and high risk results down-graded to E alone. None of 46 pts initially favouring E alone who were low risk changed decisions. 82.8% who initially wanted E+C and had low risk scores downgraded to E alone. Endopredict results increased oncologists’ confidence (8% ‘strongly agreed’ pre-test, 50% post-test). Oncologists neither agreeing nor disagreeing with decisions fell (24% to 5%). Anxiety was stable in pts with unchanged decisions. Pts whose tmt was downgraded had significantly lower anxiety scores (p < 0.01); those whose tmt was upgraded had increased scores (p < 0.001). Likewise overall uncertainty on DCS fell post-test (p < 0.023). Conclusions: EndoPredict scores increased oncologists’ and pts’ decision-making confidence, generally improved the matching of risk with therapy decisions. Clinical trial identification: ISRCTN69220108 Legal entity responsible for the study: David Bloomfield Funding: Myriad Genetics Disclosure: L. Fallowfield, D. Bloomfield: Educational grant from Myriad Genetics. J. Mackay: Consultancy role to Myriad Genetics and travel expenses. S. Hinde: Educational grant from Myriad Genetics. A. Moss: Consultancy for Myriad Genetics. All other authors have declared no conflicts of interest.