Gene expression signatures (GES) have emerged to predict prognosis and guide the use of adjuvant therapy in patients with hormone receptor-positive HER2-negative (HR+/HER2-) early breast cancer (eBC). However, very limited data is available in older patients, especially direct comparative information.
We tested and compared the prognostic value of four GES (Oncotype Dx Recurrence Score (RS), PAM50-based Prosigna (ROR), MammaPrint 70-gene (Prog70), and EndoPredict (EPclin)) in 3,533 operated and chemotherapy-naïve patients with pN0/pN1 HR+/HER2- eBC, according to a 70-year age cutoff, from a pooled dataset of 12,677 BC patients. The primary endpoint was Relapse-Free Survival (RFS).
Median follow-up for this analysis was 81.1 months. RFS events were recorded in 269 of the 1,167 patients ≥70 years (23%) and in 399 of the 2,366 patients <70 years (17%). Concordance tests of the four signatures did not differ between the two age groups (concordance mean of 77% and 78%, in the ≥70 and <70 groups, respectively;
We observed good prognostic performances of the four GES in patients <70, as previously described. By contrast, our results in patients ≥70 are equivocal and suggest that GES should be used with caution in this population. Further development and validation may be needed in this particular setting.
Has not received any funding.
A. De Nonneville: Non-Financial Interests, Personal, Advisory Board: Gilead, Daiichi Sankyo, Seagen, Lilly, Novartis, MSD. A. Gonçalves: Financial Interests, Institutional, Invited Speaker: Novartis, Roche, MSD, AstraZeneca, daiichy sanko. All other authors have declared no conflicts of interest.