Prognostic Tools for Early-Stage HER2+ Breast Cancer

A review of data presented at the 2020 San Antonio Breast Cancer Symposium (SABCS) examining the development and validation of prognostic tools for early stage HER2+ breast cancer.

Data from the following clinical trials are discussed:

• First results from a phase 3 randomized clinical trial of standard adjuvant endocrine therapy (ET) +/- chemotherapy (CT) in patients (pts) with 1–3 positive nodes, hormone receptor–positive (HR+) and HER2-negative (HER2-) breast cancer (BC) with recurrence score (RS) < 25: SWOG S1007 (RxPONDER) (Kalinsky K, et al. 2020 SABCS. Poster GS3-00).

• Primary outcome results from the WSG-ADAPT HR+/HER2- trial: Endocrine therapy alone in patients with intermediate or high-risk luminal early breast cancer (0–3 lymph nodes), Recurrence Score <26 and Ki67 response after preoperative endocrine therapy (Harbeck N., et al. 2020 SABCS. Poster GS4-04).

• Continued efficacy of neratinib in patients with HER2-positive early stage breast cancer: Final overall survival analysis from the randomized phase 3 ExteNET trial (Holmes FA, et al. 2020 SABCS. Poster PD3-03).

• Bringing diarrhea under CONTROL: Dose escalation reduces neratinib-associated diarrhea and improves tolerability in HER2-positive early stage breast cancer (Ruiz-Borrego M, et al. 2020 SABCS. Poster PS13-20).

• The DAPHNe trial: A feasibility study of chemotherapy de-escalation based on response to neoadjuvant paclitaxel-HP (THP) in HER2-positive breast cancer (Waks AG, et al. 2020 SABCS. Poster PD3-05).

• Prognostic role of distant disease-free interval from completion of adjuvant trastuzumab in HER2-positive early breast cancer: Analysis from the ALTTO (BIG 2-06) trial (Lambertini M, et al. 2020 SABCS. Poster PD3-04).