Capecitabine (Xeloda®: F Hoffmann-La Roche, Basel, Switzerland) is an oral fluoropyrimidine carbamate rationally designed to generate 5-FU preferentially in tumour tissue through exploitation of higher intratumoral concentrations of thymidine phosphorylase (Miwa et al, 1998; Schüller et al, 2000). Here, TYMP is linked to neoplasm.