Impact of Maintenance Therapy with Capecitabine vs Observation in Triple-Negative Breast Cancer

Abstract

Background: Triple-negative breast cancer (TNBC) is a great challenge in modern oncology due aggressive biological behavior. Chemotherapy is the only treatment option for those patients. This rises the idea of using capecitabine as maintenance therapies to reduce the risk of relapse after adjuvant treatment.   Patients and Methods: This is a retrospective study done on 2 groups of patients with TNBC after completion of standard treatment. group 1 received capecitabine twice daily for 14 days and one-week rest for 6 months and group 2 was under observation. Aim: To compare the 3 years DFS and OAS between both groups and to assess the toxicity in group 1. Results: 112 cases were included in group 1 and 115 cases in group 2. The median follow-up period was 42 months. Patients characteristics were comparable between both groups. The results were numerically better in group 1 but did not reach significant level regarding incidence of events (44 vs 51), OS 49.4 (95% confidence interval 43.6-55.2) vs 46.2 (95% CI 42.6-49.7) months and DFS 44.1 (95% CI 34.3-53.9) vs 40.9 (95% CI 33.1-48.5) months. The significant effect was observed in subgroup of cases with early nodal disease where OS was 54.3 (95% CI 53.5-55.2) vs 44.5 (95% CI 43.2-45.9) months (P- value 0.03) and DFS was 48.3 (95% CI 44.8-53.7) vs 39.9 (95% CI 33.5-46.2) months (P-value 0.04). Also, in cases who achieved PCR where OS was 54.7 (95% CI 53.7-55.8) vs 44.2 (95% CI 43-45.2) months (P-value 0.02) and DFS was 48.8 (95% CI 40.7-53.8) vs 39.2 (95% CI 34.3-44) months (P-value 0.03). the maintenance therapy was well tolerated with no need to stop the treatment or reduce the dose. Conclusion: Low dose capecitabine therapy numerically improves OS and DFS in cases with TNBC. The improvement is significant in early nodal disease cases and cases who achieved PCR. The therapy is well tolerated with no remarkable toxicity.