Limited potency of adjuvant capecitabine treatment in TNBC patients with residual invasive disease.

Abstract

The triple negative breast cancer (TNBC) is one of the sub-types of breast cancers. This subtype is not only very aggressive, but also has worse prognosis, than the others. For instance, patients without pathological complete response (pCR) after NACT have a 20 - 30% risk of relapse of the disease within 2 years. The adjuvant maintenance treatment options for this group of patients who do not achieve pCR are limited. Capecitabine, an anti-metabolite that has been shown to be effective for other cancers such as, Gastro-intestinal cancers is among the most commonly used drug for the TNBC with residual invasive carcinoma. However, given the heterogeneity of TNBC, aggressiveness of the sub-type, the overall poor prognosis, high dosage required for efficacy, associated toxicity or intolerability of the drug, there is need for determination and development of new therapies, treatment modalities or strategies to optimize response rates as well as management of severe side effects. The aim of the meta-analysis was to assess the absolute benefits, weighed against the adverse effects of capecitabine therapy in TNBC patients with residual invasive disease compared with other standard treatment options. The 5- year overall treatment effect defined as the overall survival hazard ratio for death was 1.09 (0.75-1.64), the average relative risk reduction of death only 11.9%. Increased events including grade 3 and 4 haematological, gastrointestinal toxicities and hand-foot syndrome were noted in the capecitabine treatment arm compared to controls. The limited potency as seen in the marginal overall survival advantage and adverse effects highlights the need for careful selection of patients who may and may not benefit from the treatmen