Abstract
INTRODUCTION: Rates of downstaging and tolerability to NAC in women age ≥ 70 years with operable breast cancer have not been well studied. We sought to compare downstaging rates and NAC completion between women age 50-69 years and age ≥ 70 years. METHODS: Consecutively treated women age ≥ 50 years with cT1-3N0-1 breast cancer receiving NAC followed by surgery from November 2013 to April 2020 were studied. Rates of downstaging from breast-conserving surgery (BCS)-ineligible to BCS-eligible and avoidance of axillary dissection (ALND) in cN1 patients were compared between patients age 50-69 and ≥ 70 years. NAC regimens and rates of completion also were assessed. RESULTS: Overall, 651 women, age ≥ 50 years, with 668 cT1-3N0-1 breast cancers that were treated with NAC, were identified; 75 (11.1%) were age ≥ 70 years. Patients age ≥ 70 years were less likely to have lobular cancers (5% vs. 10%, p = 0.03), receive an anthracycline-based regimen (69% vs. 93%, p < 0.001), and complete their entire prescribed regimen (57% vs. 78%, p < 0.001). Of 312 BCS-ineligible patients eligible for downstaging, conversion rates to BCS-eligibility were similar between age groups (72% [≥ 70] vs. 74% [50-69], p > 0.9). Women age ≥ 70 years who converted to BCS-eligible post-NAC were more likely to undergo BCS than younger patients (93% vs. 74%, p = 0.04). Of 390 cN1 patients, 162 (42%) achieved a nodal pCR; ALND avoidance was similar between age groups (43% [≥ 70] vs. 42% [50-69], p > 0.9). CONCLUSIONS: While patients age ≥ 70 years received less anthracycline-based NAC and were less likely to complete their prescribed regimen, they experienced high rates of breast and axillary downstaging, similar to younger patients, suggesting that well-selected elderly patients can safely receive NAC with substantial clinical benefit.