title: An immunoassay method for the pharmacokinetics of 5-fluorouracil in patients with gastric cancer administered adjuvant chemotherapy.
abstract: Conventional gas chromatography-mass spectrometry (GC-MS) was compared with a new immunoassay method for measuring plasma (5-FU) concentrations in adjuvant chemotherapy with TS-1 for patients with gastric cancer. TS-1 was administered orally to patients after gastrectomy. Blood samples for pharmacokinetic analysis were collected on the seventh day of treatment. The mean area under the time concentration curve (AUC)(0-8), half-life (t(1/2)), and maximum drug concentration (C(max)) obtained by the two methods were as follows: GC-MS, 847.9 μg/ml/hr, 2.76 h, and 186.6 ng/ml; and immunoassay, 1311.2 μg/ml/hr, 3.5 h, and 259.8 ng/ml. Significant correlations were observed for AUC(0-8) (p=0.0001), C(max) (p=0.0007), and changes in the 5-FU concentration in blood over time (p=0.018) for the two methods. Compared with the conventional GC-MS method, the new immunoassay method provides similar results, but is simpler and results can be obtained earlier. This method will be useful for monitoring the 5-FU concentration in serum from patients with gastric cancer receiving TS-1.
authors.affiliation: Department of Digestive Surgery, Kawasaki Medical School, 577 Matsushiama, Kurashiki City, Okayama, 701-0192, Japan. h-matsu@med.kawasaki-m.ac.jp
authors.forename: Hideo
authors.initials: H
authors.lastname: Matsumoto
authors.forename: Masaharu
authors.initials: M
authors.lastname: Higashida
authors.forename: Hisako
authors.initials: H
authors.lastname: Kubota
authors.forename: Haruaki
authors.initials: H
authors.lastname: Murakami
authors.forename: Kosuke
authors.initials: K
authors.lastname: Tsutsumi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakashima
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Oka
authors.forename: Hideo
authors.initials: H
authors.lastname: Okumura
authors.forename: Masafumi
authors.initials: M
authors.lastname: Nakamura
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Hirai
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D017024:Chemotherapy, Adjuvant; D004338:Drug Combinations; D005260:Female; D005472:Fluorouracil / Q000097:blood / Q000493:pharmacokinetics*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008297:Male; D010094:Oxonic Acid / Q000493:pharmacokinetics / Q000627:therapeutic use; D013274:Stomach Neoplasms / Q000188:drug therapy*; D005641:Tegafur / Q000493:pharmacokinetics / Q000627:therapeutic use
chemical_list: D000970:Antineoplastic Agents; D004338:Drug Combinations; C079198:S 1 (combination); D005641:Tegafur; D010094:Oxonic Acid; D005472:Fluorouracil