title: Letter to the editor: "Phase II trial of S-1 monotherapy in elderly or frail patients with metastatic colorectal cancer".
authors.forename: M J
authors.initials: MJ
authors.lastname: Molina-Garrido
authors.forename: Carmen
authors.initials: C
authors.lastname: Guillén-Ponce
mesh_terms: D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use*; D017322:Clinical Trials, Phase II as Topic / Q000379:methods; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000473:pathology; D004338:Drug Combinations; D016330:Frail Elderly; D006305:Health Status Indicators; D006801:Humans; D009367:Neoplasm Staging; D010094:Oxonic Acid / Q000627:therapeutic use*; D005641:Tegafur / Q000627:therapeutic use*
chemical_list: D000964:Antimetabolites, Antineoplastic; D004338:Drug Combinations; C079198:S 1 (combination); D005641:Tegafur; D010094:Oxonic Acid