cisplatin + tegafur + uracil + leucovorin

A combination chemotherapy regimen consisting of **cisplatin** (a platinum-based alkylating agent), **tegafur** (a prodrug of 5-fluorouracil), **uracil** (inhibits 5-FU degradation), and **leucovorin** (a reduced folate that enhances 5-FU activity). This regimen leverages synergistic mechanisms: cisplatin forms DNA crosslinks causing apoptosis; tegafur is converted to 5-FU, which inhibits DNA synthesis; uracil increases 5-FU bioavailability; leucovorin stabilizes the ternary complex between 5-FU metabolites and thymidylate synthase, amplifying antitumor effects. Used primarily as an anticancer protocol in gastrointestinal, head and neck, and nasopharyngeal carcinomas[2][3][4].