Key clinical point: In estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2−) breast cancer (BC) neoadjuvant chemotherapy (NAC) should be considered to enable axillary conservation in patients aged <50 years with Ki67 ≥20%.
Major finding: Both Ki67 ≥20% (adjusted odds ratio [aOR] 2.60; P = .04) and age <50 years (aOR 2.44; P = .01) were significant independent predictors of nodal pathological complete response (pCR). Younger patients (<50 years) had a higher nodal pCR when Ki67 index was ≥20% vs. <20% (35.8% vs. 14.3%; P = .02), whereas older patients (≥50 years) had an extremely low nodal pCR when Ki67 was <20% vs. ≥20% (2.6% vs. 21%; P = .008).
Study details: This study included 315 patients with node-positive, stage I-III, ER+/HER2− BC who were treated with NAC followed by surgery.
Disclosures: This work was partly supported by the National Institutes of Health Mayo Clinic Breast SPORE grant. Dr. Goetz and Dr. Boughey declared having research collaboration and receiving grants, funding, personal fees, or consulting fees from several sources.
Source: Boughey JC et al. Neoadjuvant chemotherapy and nodal response rates in luminal breast cancer: effects of age and tumor Ki67. Ann Surg Oncol. 2022 (May 15). Doi: 10.1245/s10434-022-11871-z