Recurrence Score-guiding Chemotherapy in Non-pCR HR Positive HER2 Negative Breast Cancer After Neoadjuvant Therapy

Multi Gene Detection Tool Based Recurrence Score-guiding Chemotherapy in Non-pathologic Complete Response HR Positive and HER2 Negative Breast Cancer After Neoadjuvant Treatment

The luminal subtype of breast cancer means hormone receptor positive, human epidermal growth factor receptor 2 negative (HR+HER2-), which counted 60%-70% of breast cancer but achieve low pathologic complete response (pCR) rate (7.5%-15%) in neoadjuvant chemotherapy. It is controversial whether additional chemotherapy after surgery is necessary for those non-pCR HR+HER2- patients. Multiple gene is a mature diagnose tool for recurrence score in adjuvant treatment strategy. This study is to investigating the value of multi gene detection tool based recurrence score for guiding additional chemotherapy after surgery in HR+HER2- non-pCR breast cancer.

This study is designed as stratified cluster randomized, parallel-control research. The HR+HER2- breast cancer patients after neoadjuvant chemotherapy (including anthracyclines and taxane, at least 6 cycles) assessed non-pCR are recruited, receiving multiple gene test before neoadjuvant treatment and after surgery. After enrollment, the patients were stratified according to multiple gene test based recurrence risk level (High risk or Low risk) and then randomized into two groups respectively in each cluster: receiving additional chemotherapy (Capecitabine) group or negative control group. The primary endpoint is 2-year disease free survival. The second endpoint is 5-year disease free survival (DFS), 2-year overall survival (OS), 5-year OS, safety of additional chemotherapy. The exploratory endpoint is the variety of multiple gene test based recurrence risk after neoadjuvant chemotherapy in non-pCR patients.

Inclusion Criteria:

1. Invasive breast cancer at the first diagnosed
2. Clinical stage cT1-4cN0-3M0 (AJCC 8th), receiving neoadjuvant chemotherapy at least 6 cycles
3. Neoadjuvant chemotherapy regimen should include anthracyclines and taxane
4. Primary tumor HR+(ER+ or PR+) and HER2 negative before neoadjuvant chemotherapy
5. Pathological evaluation non-pCR after neoadjuvant chemotherapy (residual invasive cancer in primary tumor)

Exclusion Criteria:

1. Metastasis, recurrent breast cancer or receiving other treatment before neoadjuvant chemotherapy
2. Pregnant breast cancer
3. IHC or FISH test of primary tumor confirmed HER2 positive at anytime
4. Complete fewer than 6 cycles chemotherapy before surgery
5. Deficiency of surgery after neoadjuvant
6. Contraindication of chemotherapy or surgery