Capecitabine for ER-positive versus ER-negative breast cancer

Features of durable response and treatment efficacy for capecitabine monotherapy in advanced breast cancer: real-world evidence from a large single-centre cohort

“…One of the final steps in this activation pathway is catalysed by thymidine phosphorylase, present in 3-10-fold higher concentration in cancer cells compared to normal cells. Consequently, the effect of capecitabine is concentrated within these cancer cells and therefore causes less systemic toxicity events (Miwa et al 1998;Saif et al 2008;White et al 2014). Thymidine phosphorylase also converts 5-FU to fluorodeoxyuridine monophosphate which causes inhibition of thymidylate synthase.…”