In a systematic review and meta-analysis reported in JAMA Surgery, Samiei et al found that among breast cancer subtypes, the highest rates of axillary node pathologic complete response following systemic neoadjuvant therapy were in patients with hormone receptor (HR)-negative, HER2-positive disease and those with HER2-positive (HR-negative or HR-positive) disease.
Study Details
The analysis included data from 33 studies in the neoadjuvant setting reported through July 2020, including 57,531 patients with initially clinically node-positive disease. In 23 studies, all patients (n = 9,961) had pathologically proven axillary node metastases prior to neoadjuvant therapy. Axillary pathologic complete response rates were determined for seven breast cancer subtypes.
Key Findings
Axillary pathologic complete response rates were:
- 60% for HR-negative/HER2-positive disease (23 studies, n = 7,132)
- 59% for HER2-positive (HR-negative or HR-positive) disease (9 studies, n = 764)
- 48% for triple-negative disease (30 studies, n = 14,521)
- 45% for HR-positive/HER2-positive disease (17 studies, n = 8,168)
- 35% for luminal B disease (5 studies, n = 468)
- 18% for HR-positive/HER2-negative disease (25 studies, n = 26,332)
- 13% for luminal A disease (5 studies, n = 156).
Axillary pathologic complete response rates for patients with pathologically proven axillary metastasis vs those without (or not always) pathologically proven metastasis were:
- 60% vs 60% for HR-negative/HER2-positive disease
- 59% vs 56% for HER2-positive (HR-negative or HR-positive) disease
- 48% vs 50% for triple-negative disease
- 45% vs 47% for HR-positive/HER2-positive disease
- 35% vs 33% for luminal B disease
- 18% vs 18% for HR-positive/HER2-negative disease
- 13% vs 19% for luminal A disease.
The investigators concluded, “The HR-negative/HER2-positive subtype was associated with the highest axillary [pathologic complete response] rate. These data may help estimate axillary treatment response in the neoadjuvant setting and thus select patients for more or less invasive axillary procedures.”
Sanaz Samiei, MD, of the Department of Surgery, Maastricht University Medical Center, the Netherlands, is the corresponding author for the JAMA Surgery article.
Disclosure: The study was supported by the Dutch Cancer Society and Alpe d’Huzes Foundation. For full disclosures of the study authors, visit jamanetwork.com.
