The authors evaluated the influence of 5-fluorouracil (5-FU) on treatment tolerability in 81 colorectal cancer patients given adjuvant 5-FU intravenously plus folinic acid for 6 cycles. The pharmacokinetics of 5-FU and its inactive metabolite 5-fluoro-5,6-dihydrouracil (5-FDHU) were measured on days 1 and 5 of the first chemotherapy cycle, 5 and 45 minutes after bolus administration. 5-FU clearance was significantly lower on day 5 (62.
View Article and Find Full Text PDFPurpose: To evaluate 5-fluorouracil (5-FU) and 5-fluoro-5,6-dihydrouracil (5-FDHU) pharmacokinetics and disease-free survival (DFS) in colorectal cancer patients given 5-FU-based adjuvant chemotherapy within a nonrandomized, retrospective, pharmacokinetic study.
Experimental Design: One hundred fifteen patients including 72 men (median age, 63 years; range, 36-79 years) and 43 women (median age, 60 years; range, 36-73 years) received 6 cycles of l-leucovorin 100 mg/m(2)/day and 5-FU 370 mg/m(2)/day i.v.
Objective: To compare thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD) and thymidine phosphorylase (TP) gene polymorphism and expression in colorectal cancer (CRC), and normal mucosa in chemotherapy-naïve patients.
Methods: TS, DPD and TP mRNA expression was analysed by real-time reverse-transcription polymerase chain reaction in primary CRC and adjacent normal tissues from 53 patients with glyceraldehyde-3-phosphate dehydrogenase as housekeeping gene. TS promoter (TSER and C/G SNP) and DPD IVS14+1G>A genotypes were determined by polymerase chain reaction and restriction fragment length polymorphism assays.
Purpose: Recent clinical studies have demonstrated a reduction of irinotecan (CPT-11) gastrointestinal toxicities when the CPT-11 is administered in combination with thalidomide in patients with diagnosis of colorectal cancer. The main purpose of this study was to investigate possible interactions between CPT-11 pharmacokinetics and thalidomide to explain the previously described gastrointestinal toxicity reduction.
Methods: In our clinical trial, advanced cancer patients were treated with CPT-11 on a dose of 350 mg/m2 at day 1 every 3 weeks.
Administration of 5-fluorouracil (5-FU) may be associated with severe toxicities in patients who are deficient of dihydropyrimidine dehydrogenase (DPD) activity. For this reason, a sensitive HPLC method for the analysis of 5-FU and 5-fluoro-5,6-dihydrouracil (5-FDHU) was developed in the present study for the determination of DPD activity in nucleated cells of peripheral blood and pharmacokinetic analysis of 5-FU and 5-FDHU in humans. 5-FU and 5-FDHU were extracted from biologic matrices by adding sodium acetate, sodium sulfate, and diethyl ether/propanol.
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