RESUMO
Purpose: Results from studies of extended capecitabine after the standard adjuvant chemotherapy in early stage triple-negative breast cancer (TNBC) were inconsistent, and only low-dose capecitabine from the SYSUCC-001 trial improved disease-free survival (DFS). Adjustment of the conventional adjuvant chemotherapy doses affect the prognosis and may affect the efficacy of subsequent treatments. This study investigated whether the survival benefit of the SYSUCC-001 trial was affected by dose adjustment of the standard adjuvant chemotherapy or not. Patients and Methods: We reviewed the adjuvant chemotherapy regimens before the extended capecitabine in the SYSUCC-001 trial. Patients were classified into "consistent" (standard acceptable dose) and "inconsistent" (doses lower than acceptable dose) dose based on the minimum acceptable dose range in the landmark clinical trials. Cox proportional hazards model was used to investigate the impact of dose on the survival outcomes. Results: All 434 patients in SYSUCC-001 trial were enrolled in this study. Most of patients administered the anthracycline-taxane regimen accounted for 88.94%. Among patients in the "inconsistent" dose, 60.8% and 47% received lower doses of anthracycline and taxane separately. In the observation group, the "inconsistent" dose of anthracycline and taxane did not affect DFS compared with the "consistent" dose. Moreover, in the capecitabine group, the "inconsistent" anthracycline dose did not affect DFS compared with the "consistent" dose. However, patients with "consistent" taxane doses benefited significantly from extended capecitabine (P=0.014). The sufficient dose of adjuvant taxane had a positive effect of extended capecitabine (hazard ratio [HR] 2.04; 95% confidence interval [CI] 1.02 to 4.06). Conclusion: This study found the dose reduction of adjuvant taxane might negatively impact the efficacy of capecitabine. Therefore, the reduction of anthracycline dose over paclitaxel should be given priority during conventional adjuvant chemotherapy, if patients need dose reduction and plan for extended capecitabine.
RESUMO
BACKGROUND AND OBJECTIVES: To evaluate the potential benefits of Bacteroides fragilis 839 (BF839), a next-generation probiotics, in reducing myelosuppression and gastrointestinal toxicity associated with chemotherapy in breast cancer patient. METHODS AND STUDY DESIGN: 40 women with early breast cancer were randomly assigned to the BF839 (n=20) or placebo (n=20) during the administration of adjuvant chemotherapy (4 cycles of epirubicin 100mg/m2 and cyclophosphamide 600mg/m2). Myelosuppression and gastrointestinal adverse effects were monitored in both groups. RESULTS: Throughout the four treatment cycles, the percentage of patients experiencing myelosuppression was 42.5% in the BF839 group, significantly lower than the 66.3% observed in the control group (p=0.003). Two patients in the BF839 group and three patients in the placebo group received recombinant human granulocyte colony-stimulating factor (rhG-CSF) due to leuko-penia/neutropenia. When considering an ITT analysis, which included all patients regardless of rhG-CSF treatment, the BF839 group exhibited less reduction from baseline in white blood cells (-0.31±1.19 vs -1.15±0.77, p=0.012) and neutrophils (0.06±1.00 vs -0.84±0.85, p=0.004) compared to the placebo group. The difference became even more significant when excluding the patients who received rhG-CSF injections. Throughout the four treatment cycles, compared to the placebo group, the BF839 group had significantly lower rates of 3-4 grade nausea (35.0% vs 71.3%, p=0.001), vomiting (20.0% vs 45.0%, p=0.001), and diarrhea (15.0% vs 30.0%, p=0.023). CONCLUSIONS: These findings suggest that BF839 has the potential to effectively mitigate myelosuppression and gastrointestinal toxicity associated with chemotherapy in breast cancer patients.