Comparative Study on Two Post-operative Adjuvant Chemotherapy Regimens for Treating Triple-negative Breast Cancer

Post-operative adjuvant chemotherapy has been shown to improve overall survival, delay local relapse and reduce distant metastasis by multiple large-scale prospective clinical trial. In registry clinical trial for Capecitabine conducted by O Shaughnessy, it revealed that a combined chemotherapy of Capecitabine and Docetaxel achieved better outcomes compared with Docetaxel alone. And the significant effect of Capecitabine was also evidenced by CHAT trial in which Trastuzumab/Docetaxel/Capecitabine regimen was proved to perform greater than Trastuzumab/Docetaxel regimen. In addition to better outcomes, Capecitabine also showed good tolerance and safety profile. In 2009, Finnish Breast Cancer Group published their study results from FinXX clinical trial on Lancet Oncology, and in this trial, they compared the efficacy between sequential Docetaxel (3 cycles) followed by 3 cycles of Fluorouracil/Epirubicin/Cyclophosphamide (FEC) and sequential Docetaxel and Capecitabine (3 cycles) followed by 3 cycles of Capecitabine/Epirubicin/Cyclophosphamide (XEC) in lymph positive or high-risk lymph negative early-stage breast cancer patients. And their results showed a better outcome in TX-XEC regimen. 5-year follow-up analysis of this trial revealed that combined Capecitabine regimen can bring more significant clinical benefits to triple-negative breast cancer patients. Another clinical trial NO1062 released their preliminary results on comparison of AC-T and AC-XT regimens and it showed that combined Capecitabine regimen can significantly improve overall survival and this effect is more obvious in triple--negative breast cancer patients. Based on the results of FinXX and NO1062, it's of great value to optimize combined Capecitabine regimen and clarify involved questions, such as whether the efficacy of Capecitabine is related to its treatment course or not, whether Capecitabine should be combined into current standardized chemotherapy or a sequential therapy. Also, there are still no clear conclusions on the best post-operative adjuvant chemotherapy for triple--negative breast cancer patients. Especially in Chinese population, the efficacy and safety of Capecitabine in adjuvant chemotherapy has not been well established. So it's necessary to explore reasonable dosage, safety profile and efficacy of combined Capecitabine therapy. Based on this purpose, this study is hoped to compare efficacy and safety of sequential Docetaxel followed by Fluorouracil/Epirubicin/Cyclophosphamide (FEC) and sequential Docetaxel and Capecitabine followed by Capecitabine/Epirubicin/Cyclophosphamide (XEC) as post-operative adjuvant chemotherapy in the treatment of triple-negative breast cancer in Chinese population.