A prognostic value of BCT gene score in ER+HER2-breast cancer patients with 21-gene recurrence score

초록

Background GenesWell BCT is a prognostic test that incorporates both genetic (6 prognostic and 3 reference genes) and clinicopathological factors (nodal status, tumor size) and derives a BCT Score that predicts risk of recurrence in patients with early breast cancer. The aim of this study was to develop a BCT Gene Score that excludes clinicopathological factors from the BCT score, and to evaluate its prognostic performance. Methods We investigated the prognostic performance of the novel prognostic score derived from GenesWell BCT in a cohort of ER+/HER2- patients with Oncotype DX Recurrence Score. The primary endpoints were inter-test agreement and recurrence-free survival (RFS). Results Analysis of 759 samples collected from five Korean institutions showed 81.2% concordance in risk classification between BCT Gene Score and BCT Score. The concordance rate between BCT Gene Score and Oncotype DX Recurrence Score was 74.2%, indicating moderate concordance. All these prognostic indices showed significant prognostic performance in the overall cohort (p-values<0.05). In particular, the combination of GenesWell BCT’s BCT Score and BCT Gene Score provided more prognostic information than either alone. Patients classified as high risk by either prognostic score had a significantly worse prognosis than those classified as low risk by both methods. Furthermore, in the low-risk group according to Oncotype DX Recurrence Score, patients classified high risk by BCT Score and/or BCT Gene Score showed poor prognosis compared to other patients. Conclusions These results suggest that the addition of the BCT Gene Score to the BCT Score of GenesWell BCT allows for more accurate prediction of prognosis in patients with early breast cancer.