Using Oncotype DX breast recurrence score® assay to define the role of neoadjuvant endocrine therapy in early-stage hormone receptor-positive breast cancer

• Published in: Breast cancer research and treatment Vol. 199; no. 1; pp. 91 - 98
• Main Authors: Taylor, Caitlin, Meisel, Jane, Foreman, Aimee J., Russell, Christy, Bandyopadhyay, Dipankar, Deng, Xiaoyan, Floyd, Lisa, Zelnak, Amelia, Bear, Harry, O’Regan, Ruth
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.05.2023; Springer; Springer Nature B.V
• Subjects: Adjuvant treatment; Breast cancer; Breast Neoplasms - drug therapy; Breast Neoplasms - genetics; Breast Neoplasms - pathology; Cancer; Cancer research; Cancer therapies; Chemotherapy; Chemotherapy, Adjuvant; Clinical Trial; Decision making; Diseases; Endocrine therapy; Female; Gene Expression Profiling - methods; Hormones; Humans; Medicine; Medicine & Public Health; Neoadjuvant Therapy; Neoplasm Recurrence, Local - drug therapy; Neoplasm Recurrence, Local - genetics; Neoplasm Recurrence, Local - pathology; Oncology; Patients; Prognosis; Relapse; Statistical analysis; Surgery; Endocrine therapy; Recurrence Score; Neoadjuvant therapy; Hormone receptor-positive breast cancer; Oncotype
• ISSN: 0167-6806; 1573-7217
• DOI: 10.1007/s10549-023-06890-7

Purpose The role of neoadjuvant endocrine therapy in the treatment of patients with early-stage, hormone receptor-positive (HR +) breast cancer is not well defined. Tools to better determine which patients may benefit from neoadjuvant endocrine therapy versus chemotherapy or upfront surgery remain an unmet need. Methods We assessed the rate of clinical and pathologic complete response (cCR, pCR) among a pooled cohort of patients with early-stage HR + breast cancer who had been randomized to neoadjuvant endocrine therapy or neoadjuvant chemotherapy in two earlier studies to understand better how outcomes varied by Oncotype DX Breast Recurrence Score® assay. Results We observed that patients with intermediate RS results had no statistically significant differences in pathologic outcomes at the time of surgery based on whether they received neoadjuvant endocrine therapy or neoadjuvant chemotherapy, suggesting that a subgroup of women with a RS 0–25 may omit chemotherapy without compromising outcomes. Conclusion These data suggest that Recurrence Score® (RS) results may serve as a useful tool in treatment decision-making in the neoadjuvant setting.