Where does the OPTIMA trial, presented at ASCO 2026, fit into decision-making for chemotherapy for premenopausal women with high clinical and low genomic risk ER+ breast cancer?

Since the median follow-up on this trial was only 4 years (which is considered short for patients with operable, hormone receptor-positive, HER2-negative breast cancer) and since the study has not yet been published in a peer-reviewed journal, I would exercise extreme caution in skipping potentially life-saving adjuvant chemotherapy for women with metastatic disease in up to 9 axillary lymph nodes and low genomic risk. I have not yet incorporated this approach into my practice at this time. Howe...

For premenopausal patients with pN2/pN3, the current guideline recommendation is adjuvant chemotherapy followed by endocrine therapy ± ovarian suppression/ablation (category 1), with no genomic assay step in the decision pathway. No genomic assay is validated yet.

The OPTIMA trial presented at ASCO 2026 provides the first prospective randomized evidence that a genomic assay (Prosigna/PAM50) can guide chemotherapy decisions in patients with pN2 disease, which could indeed shift practice for this ...