Capecitabine-based Combination Chemotherapy Followed By Single-agent Capecitabine Maintenance Therapy In Metastatic Breast Cancer

Purpose:We performed this study to evaluate efficacy and safety of capecitabine-based combination chemotherapy followed by single-agent capecitabine maintenance therapy in patients with metastatic breast cancer who got disease stabilization or response in capecitabine-based combination chemotherapy.Methods:Patients with metastatic breast cancer fit with the standards of our study were enrolled in the study from April 2011 to December 2012.Patients received capecitabine-based combination chemotherapy(capecitabine plus docetaxel or Paclitaxel or vinorelbine)first,generally for four to six cycles.Then we gave single-agent capecitabine maintenance treatment to patients who got non-progressive disease in efficacy evaluation,until disease progression or severe toxicity or death.Capecitabine was administered at a dose of 1000mg/m2 twice daily for 14 days either in combination chemotherapy or in maintenance therapy.Docetaxel was administered at a dose of 75mg/m2 in the first day,Paclitaxel was at a dose of 175mg/m2 in the first day and vinorelbine was at a dose of 25mg/m2 in the first day and the eighth day.It is 21 days for one cycle.Efficacy of treatment was evaluated every two cycles,side effects were assessed every cycle.Results:29 patients were enrolled to receive capecitabine-based combination chemotherapy.28 of them were assessable for efficacy.Objective response rate(ORR)and disease control rate(DCR)was 57.1%and 78.6%respectively.19 patients received capecitabine maintenance therapy.Median progression free survival(mPFS),the primary endpoint of our study,was 11.4 months.Secondary endpoint of the study,median duration of response(mDOR),was 5.5 months.Median overall survival(mOS)was also the secondary endpoint of our 'study,due to the median follow-up time was limited,mOS cannot be estimated.The main side effect occurred in combination chemotherapy were neutropenia(82.8%),anemia(72.4%),AST(37.9%),grade ?/? neutropenia was 37.9%.The major toxicity occurred in single-agent maintenance therapy were neutropenia(52.6%),anemia(31.6%),fatigue(31.6%),hand-foot syndrome(36.8%),and the incidence rate of grade III/IV toxicity was low..There was statistically significant difference in incidence rate of Grade III/IV neutropenia and Grade I anemia between combination chemotherapy and maintenance therapy.Conclusion:1.Useing Capecitabine-based combination chemotherapy to treat metastatic breast cancer as a first-line or a second-line treatment,produced an ORR of 57.1%and a DCR of 78.6%.2.Patients who got disease stabilization or response in capecitabine-based combination chemotherapy continued receiving single-agent capecitabine maintenance therapy,got mPFS of 11.4 months and mDOR of 5.5 months.3.Either in capecitabine-based combination chemotherapy or single-agent capecitabine maintenance therapy,all toxicity of chemotherapy could be catabatic itself or be cured.This treatment is safe.