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PubMed2006

Randomized controlled trial of reduced-dose bolus fluorouracil plus leucovorin and irinotecan or infused fluorouracil plus leucovorin and oxaliplatin in patients with previously untreated metastatic colorectal cancer: a North American Intergroup Trial.

PURPOSE: Previously, we reported results of Intergroup N9741, which compared standard bolus fluorouracil (FU), leucovorin, plus irinotecan (IFL) with infused FU, leucovorin, plus oxaliplatin (FOLFOX4) and irinotecan plus oxaliplatin in patients with untreated metastatic colorectal cancer. High rates of grade > or = 3 toxicity on IFL (resulting in some deaths) led us to reduce the starting doses of both irinotecan and FU by 20% (rIFL). This article compares rIFL with FOLFOX4. PATIENTS AND METHODS: The primary comparison was time to progression, with secondary end points of response rate (RR), overall survival, and toxicity. RESULTS: Three hundred five patients were randomly assigned. The North Central Cancer Treatment Group Data Safety Monitoring Committee interrupted enrollment at a planned interim analysis when outcomes crossed predetermined stopping boundaries. The results were significantly superior for FOLFOX4 compared with rIFL for time to progression (9.7 v 5.5 months, respectively; P < .0001), RR (48% v 32%, respectively; P = .006), and overall survival (19.0 v 16.3 months, respectively; P = .026). Toxicity profiles were not significantly different between regimens for nausea, vomiting, diarrhea, febrile neutropenia, dehydration, or 60-day all-cause mortality. Sensory neuropathy and neutropenia were significantly more common with FOLFOX4. Approximately 75% of patients in both arms received second-line therapy; 58% of rIFL patients received oxaliplatin-based second-line therapy, and 55% of FOLFOX4 patients received irinotecan-based regimens as second-line therapy. CONCLUSION: FOLFOX4 led to superior RR, time to progression, and overall survival compared with rIFL. The survival benefit for FOLFOX4 observed in the earlier stage of the study was preserved with equal use of either irinotecan or oxaliplatin as second-line therapy.

Adult↗
PubMedDate not supplied

Release behaviour of 5-fluorouracil from chitosan-gel microspheres immobilizing 5-fluorouracil derivative coated with polysaccharides and their cell specific recognition.

In order to provide a device releasing drugs in a controlled manner and having targetability to specific organs or cells, chitosan-gel microspheres, CMS, crosslinked with glutaraldehyde, immobilizing 1-[N-(5-aminopentyl) carbamoyl]-5-fluorouracil, 1, coated with anionic polysaccharides, such as 6-O-carboxymethyl-N-acetyl-alpha-1,4-polygalactosamine (CM-NAPGA), 6-O-carboxymethyl-chitin, alginic acid and heparin, by polyelectrolyte complex membrane formation were prepared. When chitosan was crosslinked with glutaraldehyde, 1 was simultaneously immobilized into CMS by Schiff's base formation. Average diameter of CMS obtained was estimated to be about 0.5-1.0 micron by SEM observation. In physiological saline media, only free 5-FU was released from the CMS but 1 and any 5-FU derivative was not. Release rate of 5-FU from the CMS was reduced by coating with polyelectrolyte complex membrane of cationic chitosan and anionic polysaccharides. CMS coated with CM-NAPGA showed a lectin-mediated specific aggregation phenomenon by addition of Abrus precatorius agglutinin. Moreover, the CMS immobilizing 1 coated with CM-NAPGA showed higher growth-inhibitory effect against SK-Hep-1 (human hepatoma) cells in vitro than the CMS coated with other polysaccharides.

Carcinoma, Hepatocellular↗
PubMed1994

Double modulation of 5-fluorouracil in the treatment of advanced colorectal carcinoma: report of a trial with sequential methotrexate, intravenous (loading dose) folinic acid, 5-fluorouracil, and a literature review.

5-Fluorouracil (5-FU) modulation with either folinic acid (FA) or methotrexate (MTX) has improved 5-FU's potential cytoreductivity. We combined MTX and FA with 5-FU to further augment 5-FU's cytoreductivity. Patients (n = 34) with advanced colorectal carcinoma were first given intravenous MTX (escalated from 30 mg/m2 to 70 mg/m2). FA (100 mg/m2) was infused 17-24 hr later, followed by 5-FU (600 mg/m2). Oral rescue doses of FA were begun 24 hr after MTX. Patients were treated every 2 weeks. No previously treated patient (n = 6) responded. Eight of the remaining 28 (29%) (95% confidence interval, 15-47%) patients achieved a PR. Median survival was 9.3 months. Toxicity (primarily gastrointestinal) necessitated dosage modification in 10 patients (29%). These results, in addition to a literature review, reveal that the manipulation of 5-FU by two modulating agents does not improve the response rate seen with single-agent modulation.

Adult↗
PubMed1998

Activation of MAP kinases by 5-fluorouracil in a 5-fluorouracil-resistant variant human cell line derived from a KT breast cancer cell line.

To investigate the mechanism of the acquired resistance of human cells to an anticancer drug, 5-fluorouracil (5-FU), a drug-resistant clone, KTFU-4, was isolated from a human KT breast carcinoma cell line, treated with ethylmethanesulfonate and then with 5-FU. The viability of the KT cells, analyzed using an MTT assay, was suppressed by 5-FU in a dose-dependent manner, while that of the KTFU-4 cells was enhanced by it at concentrations between 0.1 and 1.0 microgram/ml. Treatment of KTFU-4 cells with 5-FU resulted in increased amounts of activated phosphorylated ERK1/2 and p38 MAP kinases, but not in the parent KT cells. It is thus possible that 5-FU stimulated the proliferation of KTFU-4 cells by activating a signal transduction pathway leading to cell growth.

Antimetabolites, Antineoplastic↗
PubMed2004

Leucovorin and fluorouracil vs levamisole and fluorouracil as adjuvant chemotherapy in rectal cancer.

The aim of this study was to evaluate the effectiveness of 6-month therapy with leucovorin (LV) + 5-fluorouracil (5-FU) vs 12 months of therapy with levamisole (LVZ) + 5-FU, as adjuvant chemotherapy in patients with completely resected Dukes' stage B2 or C rectal cancer. One hundred and fifty patients with surgically resected rectal carcinoma, were enrolled in the present study; Dukes' stage B2 (n=70) or C (n=80), were randomly assigned to chemotherapy with 5-FU + LV x 6 months or 5-FU + LVZ x 12 months. Patient characteristics were equally balanced between the examined groups. Adjuvant CT consisted of LV 20 mg/m(2) intravenously (i.v.) plus 5-FU 450 mg/m(2) i.v., on days 1-5 every 4 weeks for 6 cycles or 5-FU 450 mg/m(2) i.v. every week plus LVZ 50 mg t.i.d x 3 days for 1 year. All patients received radiotherapy with a three-field technique to a total dose of 45 Gy, over 5 weeks. After a median follow-up of 7.4 years there were no significant differences between the two treatment groups with respect to the recurrence rates (P=0.821). Moreover, there was no difference in disease-free survival for patients stage Dukes' B2 (log-rank p=0.73); median for LV group 90 (8-131) months, and for LVZ group 86.5 (3-129) months. No difference was noted in disease-free survival for patients stage Dukes' C (log-rank p=0.73); median for LV group 60 (17-128) months, and for LVZ group 64 (2-123) months. There was no difference in overall survival for patients stage Dukes' B2 (log-rank p=0.75); median for LV group 90 (22-131) months, and for LVZ group 86 (10-129) months. For stage Dukes' C (log-rank p=0.73); median for LV group 67 (17-128) months, and for LVZ group 64 (5-123) months. Toxicities were as follows in the 5-FU + LVZ vs 5-FU + LV group; myelosuppression (leucopenia grade 3, 12% vs 4%, p<0.04), diarrhea (grade 0, 60% vs 76%, p<0.02), and liver toxicity (increase of transaminases >3-fold, 12 patients vs 2, p<0.03), were more frequent in LVZ group. None of the patients stopped chemotherapy because of the toxicity, and there were no toxicity-related deaths. In conclusion, adjuvant chemotherapy in RC with LV + 5-FU for 6 months is equally effective and less toxic than LVZ + 5-FU for 12 months.

Adult↗
PubMed2004

[Potentiation of 5-fluorouracil efficacy. Molecular mechanisms playing a role in the cytotoxic action of 5-fluorouracil and 5-ethyl-2'-deoxyuridine (EUdR) combination].

UNLABELLED: Pharmacologic modulation of 5-fluorouracil (5-FU) metabolism provides a possibility for the enhancement of its clinical efficacy. AIM: The purpose of the present work was to study the effect of 5-ethyl-2'-deoxyuridine (EUdR), a potent 5-FU modulator, on different molecular mechanisms, influenced by 5-FU itself, and to obtain further data about the mode of action of the combination. MATERIALS AND METHODS: SW620 cell line was used for the experiments. Cytotoxicity was studied by MTT test, cell kinetic changes by FACStar flow cytometer, apoptosis by fluorescent microscope after staining the cells with acridine orange and ethydium bromide, DNA fragmentation by PAGE electrophoresis after RNase and proteinase-K digestion, thymidine incorporation with 3H-thymidine, p53 and PCNA protein expression by Western blotting. RESULTS: The cytotoxicity of 5-FU was potentiated dose dependently by EUdR. One hundred muM concentration of EUdR resulted in a 40% decrease of the IC50 value of 5-FU. Cell cycle arrest in the G2/M transition phase was most pronounced after combined treatment with 5-FU+EUdR. EUdR potentiated the incorporation of 3Hthymidine into DNA. In addition to the increase of apoptosis rate, the expression of p53 protein, caused by 5-FU was further potentiated by UdR. CONCLUSION: This study demonstrated a potential novel approach to increase the efficacy of 5-FU by EUdR, which incorporated two complementary molecular actions, the selective modulation of TS inhibition and potentiation of the p53 protein expression, consequently leading to an increase in the apoptotic rate.

Antimetabolites, Antineoplastic↗
PubMed1998

[Primary chemotherapy of metastatic breast carcinoma with bendamustine hydrochloride, methotrexate and fluorouracil versus cyclophosphamide, methotrexate and fluorouracil].

The combination bendamustine/methotrexate/fluorouracil (BMF) was proven versus cyclophosphomide/methotrexate/fluorouracil (CMF) in a stratified randomized pilot study as primary chemotherapy in 61 patients with metastatic breast cancer. Bendamustine was given in a dose of 240 mg/m2 and cyclophosphamide in a dose of 960 mg/m2 per therapy-cycle. The doses of methotrexate (40 mg/m2 i.v., day 1 and 8) and fluorouracil (500 mg/m2 i.v., day 1 and 8) were identical in both groups. 25 patients in the BMF- and 24 patients in the CMF-group were evaluable. The remission rates were 52% vs. 46%. The median duration of remission was 15.2 months (ranging from 8.1 to 19.7 months) in the BMF-group and 6.2 months (ranging from 1.9 to 11.1 months) in the CMF-group. The aim of this study was to identify the main criterion for further randomized studies. The results of this pilot study indicate, that it is possible to prolong the median duration of remission without changing the antineoplastic activity by replacing cyclophosphamide with bendamustine.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

Irinotecan versus infusional 5-fluorouracil: a phase III study in metastatic colorectal cancer following failure on first-line 5-fluorouracil. V302 Study Group.

In a multicenter phase III trial, 267 patients with nonbulky metastatic colorectal cancer who had failed first-line 5-fluorouracil (5-FU) therapy were randomized to receive second-line treatment with either the new topoisomerase agent, irinotecan (Rhône-Poulenc Rorer, Antony, France), or a high-dose infusional 5-FU regimen. Patients treated with irinotecan survived significantly longer than those treated with infusional 5-FU. The 1-year survival rate was 45% for patients receiving irinotecan compared with 32% for patients receiving 5-FU. There also was a significant difference in median progression-free survival (4.2 months v 2.9 months; P = .03) favoring irinotecan. Irinotecan administered at a dose of 350 mg/m2 every 3 weeks was associated with manageable toxicities (the main toxicities were neutropenia and diarrhea). The incidence of these adverse events and of vomiting was higher with irinotecan than with the comparator regimens of infusional 5-FU. However, the incidence of grade 3-4 asthenia was the same in the two treatment arms and mucositis and cutaneous adverse events were more common with 5-FU. Overall, mean global quality of life scores were similar in the two arms of the study throughout the period of treatment and follow-up, demonstrating that the more effective disease control achieved by irinotecan at least maintains quality of life. Indeed, deterioration in quality of life (defined as >50% decrease from baseline score) occurred significantly later in irinotecan-treated patients. In light of these data, irinotecan should be considered the reference treatment for patients with 5-FU-refractory advanced colorectal cancer.

Antimetabolites, Antineoplastic↗
PubMedDate not supplied

Possible regulation of 5-fluorouracil-induced neuro- and oral toxicities by two biochemical modulators consisting of S-1, a new oral formulation of 5-fluorouracil.

S-1 is a new oral formulation of 5-fluorouracil (5-FU) containing 1 M tegafur and 0.4 M 5-chloro-2,4-dihydroxypyridine (CDHP) and 1 M potassium oxonate (Oxo). It has been reported to have a high antitumor activity and low gastrointestinal toxicity in rats bearing murine and human tumors. We further studied the possible inhibition of the toxicities caused by the products of 5-FU metabolism with the use of CDHP, a new inhibitor of 5-FU degradation and Oxo, an inhibitor of 5-FU phosphorylation. In a model of pentylenetetrazole-induced convulsions in mice, intravenous injection of fluoroacetate (3 mg/kg), 2-fluoro-b-alanine (30 mg/kg) and 5-FU (over 300 mg/kg) significantly augmented the occurrence of convulsion. However coadministration of an equivalent dose of CDHP with 5-FU almost completely suppressed the 5-FU-augmented convulsions, suggesting that inhibition of 5-FU catabolism by CDHP may lead to a decreased risk of development of 5-FU neurotoxicity. Another advantage of the use of S-1 was protection through Oxo against the development of 5-FU-induced mucositis, which occurs frequently in cancer patients. When 6 mg/kg of S-1 was administered orally to beagle dogs for 5 days, the incidence of stomatitis decreased markedly compared to that in dogs receiving the same dose of S-1 not containing Oxo, in which severe stomatitis was frequently observed. One of the possible mechanisms of the decreased incidence of mucositis associated with oral S-1 administration is the decreased formation of 5-fluoronucleotides from 5-FU in the mucosal tissues of the oral cavity. These results suggest that oral S-1 could be employed for the treatment of cancer patients with marked reduction in the incidence of toxicities including encephalopathy, stomatitis and diarrhea.

Animals↗
PubMedDate not supplied

Different pathways of 5-fluorouracil metabolism after continuous venous or bolus injection in patients with colon carcinoma: possible predictive value of thymidylate synthetase mRNA and ribonucleotide reductase for 5-fluorouracil sensitivity.

BACKGROUND: The mode of action of 5-fluorouracil (5-FU) was evaluated in patients with advanced colon cancer treated preoperatively with 5-FU. PATIENTS AND METHODS: After obtaining informed consent, 30 patients were randomized into three groups: untreated controls (n = 16), continuous intravenous infusion of 5-FU for 5 days at a dose of 320 mg/m2 (CIV group, n = 6), or bolus intravenous injection of 5-FU for 5 days at the same dose (bolus group, n = 8). Surgically-resected samples were analyzed by 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay to detect sensitivity to 5-FU. Samples were also assayed for thymidylate synthetase (TS) activity, levels of 5-FU RNA (F-RNA), ribonucleotide reductase (RNR) activity, and TS mRNA levels expressed as the ratio of TS mRNA to beta-actin mRNA. RESULTS: While similar levels of TS inhibition were observed in the civ and bolus groups, F-RNA levels were significantly increased in the bolus group. The TS mRNA ratio was significantly higher in the 5-FU-resistant group than 5-FU-sensitive group. In the control group, the 5-FU-sensitive group showed higher RNR enzymatic activity compared to the 5-FU-resistant group. CONCLUSION: Our results suggested that the method of administration resulted in the induction of different 5-FU metabolic pathways. High TS mRNA and low RNR activity may be concerned with 5-FU-resistance in patients with advanced colon carcinoma.

Colonic Neoplasms↗
PubMedDate not supplied

A phase II study of weekly methotrexate, cisplatin, and 24-hour infusion of high-dose 5-fluorouracil and leucovorin (MP-HDFL) in patients with metastatic and recurrent esophageal cancer-improving toxicity profile by infusional schedule and double biochemical modulation of 5-fluorouracil.

BACKGROUND: Patients with advanced esophageal cancer are frequently not indicated for intensive chemotherapy due to aero-digestive tract complications. In order to improve the therapeutic index of systemic chemotherapy for these patients, we designed a weekly MP-HDFL protocol, which took advantage of the low toxicity of the infusional dosing schedule for cisplatin and 5-fluorouracil (5-FU), and double biochemical modulation of 5-FU by methotrexate and leucovorin. PATIENTS AND METHODS: Between April 1997 and April 2001, a total of 26 patients (M:F = 22:4) with a median age of 59.5 (range: 43-81) years were enrolled into this phase II clinical trial prospectively. There were 12 patients with de novo metastatic disease, 13 with recurrent disease (including 7 relapsed from previous concurrent chemoradiotherapy incorporating cisplatin and 5-FU), and one with locally advanced disease. The weekly MP-HDFL protocol was composed of methotrexate 40 mg/m2, i.v., on days 1, 8, 15; cisplatin 35 mg/m2, 24-hour IVF, on days 2, 9, 16; and 5-FU 2,600 mg/m2 and leucovorin 300 mg/m2, 24-hour IVF, on days 2, 9, 16; repeated every 28 days. RESULTS: A total of 97 courses were given with an average of 3.7 courses per patient (range: 1-19). All of the patients were assessable for evaluation of toxicity. Grades 3/4 leukopenia and thrombocytopenia were noted in 13 (14%) and 17 (18%) of the treatment courses, respectively. There were 3 episodes of febrile neutropenia in 2 patients, and lethal sepsis in one patient. The Grades 3/4 non-hematological toxicities were infrequent. Among 25 patients with recurrent or metastatic disease, 7 had partial response and 12 had stable disease. The response rate for the intent- to treat group was 28% (95% C.I.:12%-49%). The median survival was 5 months (range: 1-28 months). CONCLUSION: Weekly MP-HDFL combination chemotherapy is associated with mild and acceptable toxicity, and has modest palliative activity in a portion of advanced esophageal cancer patients. However, a more active and better tolerated anticancer drug combination is needed to improve the outcome of these patients.

Adenocarcinoma↗
PubMedDate not supplied

A randomized, comparative study of combination chemotherapies in advanced gastric cancer: 5-fluorouracil and cisplatin (FP) versus 5-fluorouracil, cisplatin, and 4'-epirubicin (FPEPIR). Kyoto Research Group for Chemotherapy of Gastric Cancer (KRGCGC).

Sixty patients with inoperable or recurrent gastric cancers were randomly assigned into 2 treatment regimens: the FP regimen, consisting of cisplatin (CDDP, 50 mg/body, d1) + 5-fluorouracil (5-FU, 250 mg/body, d2-d5), or the FPEPIR regimen, CDDP+5-FU (FP) + 4'-epirubicin (EPIR, 30 mg/m2, d2), administered intravenously every 2 weeks. The objective responses were evaluated in 43 patients (FP: 21; FPEPIR: 22). The response rates were 24% (5PR/21) for FP and 27% (6PR/22) for FPEPIR. Objective responses were seen in 1 primary lesion and 4 metastatic lesions in patients on the FP regimen, and in 3 primary lesions and 4 metastatic lesions in patients on the FPEPIR regimen. The 6 month and 1 year survival rates were 34% and 13% for FP, and 55% and 27% for FPEPIR, respectively (not significant). Significantly higher survival rates were demonstrated in those patients with recurrent cancers (p < 0.01) and those who responded to the FPEPIR regimen (p < 0.05). Drug toxicities were assessed in 56 patients, and were in general mild and well tolerated. However, the FP regimen induced significantly less neutropenia (p < 0.01) and less complete alopecia (p < 0.01) than the did FPEPIR regimen. These results suggest that FPEPIR may be a more beneficial regimen for the treatment of gastric cancer than FP, and may be indicated for further clinical trials.

Aged↗
PubMed2004

[Influence on 5-fluorouracil metabolism by combination of interferon-alpha and 5-fluorouracil against human hepatocellular carcinoma xenografts].

To investigate the effect of biochemical modulation on antitumor activity shown by the combination of 5-Fluorouracil (5-FU) and interferon-alpha (IFN-alpha), experimental therapy was performed on human hepatocellular carcinoma cell (HuH7, PLC/PLF/5) xenografts inoculated into nude mice, using 5-FU and IFN-alpha, either alone or in combination. These agents showed antitumor activity in different degrees. Although IFN-alpha, given as 100,000 units/mouse/3 times/week subcutaneously x 6, and 5-FU, given as 0.5 mg/mouse/3 times/week intraperitoneally, showed addititive antitumor effect against HuH7 and PLC/PLF/5, the activities of thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), thymidine phosphorylase (TP), orotate phosphoribosyltransferase (OPRT), uridine phosphorylase (UP) and uridine kinase (UK) were not significantly influenced in the tumors treated with the 5-FU/IFN-alpha combination, compared with those treated with 5-FU or IFN-alpha alone. This suggested that antitumor activity of 5-FU and IFN-alpha in combination was not significantly involved in 5-FU metabolism in two human hepatocellular carcinoma cell lines examined.

Animals↗
PubMed1992

[Significance of measuring 5-fluorouracil incorporated into RNA of tumor tissue as a parameter for the antitumor activity of 5-fluorouracil and its analogs].

A sensitive method for determination of incorporation of non-radiolabeled 5-fluorouracil (FUra) into RNA (F-RNA) of tumor tissue samples was established and was shown to be applicable to clinical materials. RNA fractions containing incorporated FUra were extracted from perchloric acid precipitates of tissue sonicates by KOH hydrolysis. FUra in RNA fractions was released by HCl hydrolysis at 100 degrees C and its levels were determined by GC-MS. The sensitivity of this method was 100 fold higher than that of HPLC method. F-RNA levels were dose dependent and correlated well with antitumor efficacy of the drugs. F-RNA levels in FUra resistant murine tumors were significantly lower than that in parent tumors despite of the lack of difference in FUra concentrations in tumor tissue. Based on these results, it is suggested that measurement of F-RNA levels together with the determination of FUra concentration and the inhibition rate of thymidylate synthase should be considered as a good parameters of the evaluation of antitumor efficacy of FUra and its analogs both in experimental and clinical settings.

Administration, Oral↗
PubMed2005

A multicenter randomized study comparing 5-fluorouracil continuous infusion (ci) plus 1-hexylcarbamoyl-5-fluorouracil and 5-FU ci alone in colorectal cancer.

To verify the effectiveness of oral 1-hexylcarbamoyl-5-fluorouracil (HCFU) in improving the surgical cure rate in advanced colorectal cancer, a multicenter randomized comparative study was conducted. A total of 429 patients who had had curative resection for stage II and III colorectal cancer were randomly assigned to a study group receiving a 14-day course of 5-FU continuous infusion (320 mg/m2/day) followed by oral HCFU for a year (300 mg/day), or to the control group receiving a 14-day course of 5-FU continuous infusion alone. In terms of background factors, no significant differences were found between the 214 patients in the study group and the 215 in the control group. Adverse reactions during the treatment were more frequently seen in the study group. But with few exceptions, the toxicities were mild and the compliance was acceptable. The 5-year overall survival rate of the study group was similar to that of the control group. The 5-year disease-free survival rate of the study group was better than that of the control group in the patients with colon cancer (hazard ratio=1.87; 95% confidence interval 1.03-3.38; p=0.037). However, this benefit was not seen in the patients with rectal cancer. A significant improvement in the disease-free survival rate was demonstrated through the addition of HCFU to 5-FU continuous infusion for the patients with colon cancer. The usefulness of oral fluoropyrimidine as an adjuvant for curative surgery for colon cancer was further warranted.

Adult↗
PubMed2006

Plasma level of a 5-fluorouracil metabolite, fluoro-beta-alanine correlates with dihydropyrimidine dehydrogenase activity of peripheral blood mononuclear cells in 5-fluorouracil treated patients.

5-fluorouracil (5-FU) is mostly metabolized after administration, and the metabolizing enzyme, dihydropyrimidine dehydrogenase (DPD), seems to be the rate-limiting factor. However, there are few reports on the final metabolite, fluoro-beta-alanine (FBAL). We report here the results of determination of the FBAL level in 5-FU treated patients and the correlation between the FBAL level and the DPD activity in peripheral blood mononuclear cells (PBMCs). Blood samples were collected from 20 patients, who had received continuous intravenous infusion (CIV) of 5-FU (320 mg/m2/24 hr) after resection of colorectal cancer, and the FBAL level was determined by high performance liquid chromatography (HPLC), after derivatizing into o-phthalaldehyde (OPA) and detecting fluorescence. DPD activity was measured in cytosol prepared from PBMCs using HPLC radioassay. The average FBAL plasma level during CIV of 5-FU was 911.0 ng/ml (521.0 to approximately 1834.6 ng/ml) and that of DPD activity in PBMCs was 282.6 pmol/min/mg-protein (145.0 to approximately 568.0 pmol/min/mg-protein). There was a significant correlation between the FBAL level and the DPD activity (r=0.805, p<0.0001). FBAL level in plasma may be useful in predicting the DPD activity in PBMCs, however, further studies are required considering the small number of cases in this study.

Aged↗
PubMed2006

[Plasma concentrations of 5-fluorouracil and F-beta-alanine following oral administration of S-1, a dihydropyrimidine dehydrogenase inhibitory fluoropyrimidine, as compared with protracted venous infusion of 5-fluorouracil].

The pharmacokinetics and pharmacodynamics of oral S-1, a dihydropyrimidine dehydrogenase (DPD) inhibitory fluoropyrimidine, were compared with those of protracted venous infusion (PVI) of 5-fluorouracil (5-FU). In all, 10 patients with gastric cancer received PVI of 5-FU at a dose of 250 mg/m2/day for 5 days. After a washout period of 9 days, the 10 patients received two divided doses daily for 28 days. S-1 was administered orally at about 9 a.m. and 7 p.m. Plasma concentrations of 5-FU and F-beta-alanine (FBAL) were measured for pharmacokinetic analysis, and the plasma uracil concentration was monitored as a surrogate marker of DPD inhibition in the same 10 patients on days 1-5 of PVI of 5-FU and on days 1-5 of oral S-1. The area under the curve (AUC0-10h) of 5-FU on day 5 was 728 +/- 113 ng x hr/ml for PVI of 5-FU and 1,364 +/- 374 ng x hr/ml for S-1. The median 5-FU PVI: S-1 ratio of the AUC0-10h of 5-FU was 1.9. The AUC0-10h of FBAL on day 5 of PVI of 5-FU was 9,465 +/- 3,225 ng x hr/ml, AUC0-10h, as compared with 1,725 +/- 605 ng x hr/ml on day 5 of S-1 treatment. The AUC0-10h of uracil on day 5 was 252 +/- 60 ng x hr/ml with PVI of 5-FU and 12,582 +/- 3,060 ng x hr/ml with S-1. The AUC0-10h of FBAL was markedly lower and plasma uracil concentrations were significantly higher for S-1 than for PVI of 5-FU, clearly demonstrating the effect of DPD inhibition.

Dihydrouracil Dehydrogenase (NADP)↗
PubMedDate not supplied

Hepatic arterial infusion (HAI). Comparison of 5-fluorouracil, folinic acid, interferon alpha-2b and degradable starch microspheres versus 5-fluorouracil and folinic acid in patients with non-resectable colorectal liver metastases.

BACKGROUND: The prognosis of patients with advanced colorectal tumor is poor. Therefore, other therapy regimes for non-resectable hepatic metastases are necessary. In this prospective study, two regional chemotherapy protocols were compared. PATIENTS AND METHODS: An arterial port system was implanted in 64 patients. Sixty patients were assigned to the two therapy protocols for hepatic arterial infusion (HAI): protocol A (n=24): 5-FU/FA (300 mg/m2 folinic acid and 600 mg/m2 5-fluorouracil daily for 5 days with a 14-day interval); protocol B (n=36): 5-FU/FA/IFN/DSM (450 mg starch microspheres (DSM) with 5 million IU recombinant interferon (IFN), alpha 2b 500 mg/m2 FA and 600 mg/m2 5-FU). RESULTS: The response rate was 50% in protocol A patients and 69.4% in protocol B. The median times for disease progression were 11 months for protocol A and 20 months for protocol B (p = 0.038), while median survival times of 14 months and 26 months, respectively, were obtained (p = 0.015). There were no significant differences in terms of toxic side-effects. Major toxicity problems were observed in 12% of the protocol A-treated patients and in 11% of the protocol B-treated patients. CONCLUSION: Combination therapy with HAI-5-FU/FA/IFN/DSM was superior to HAI-5FU/FA, with a high response rate (69% vs. 55%) and few toxic side-effects. These findings suggest that these combinations should be evaluated in larger studies as first- or second-line therapy in patients with hepatic metastases of colorectal cancer.

Aged↗