Phase II trial of UFT in advanced colorectal and gastric cancer

Clinical Development of new Fluoropyrimidines: A Major Improvement in Colorectal Cancer Treatment?

Aims and background

Colorectal cancer represents an increasing problem and is responsible for about 16,000 deaths per year in Italy. Fluorouracil represents the most widely used agent, but therapeutic responses have remained consistently discouraging. The overall response rates for fluorouracil as a single agent range from 5% to 15%, and the addition of biochemical modulators, although able to improve response rate, has not been shown conclusively to prolong survival.

Methods

In recent years, several new compounds characterized by a high therapeutic index, optimal absorption through the gastrointestinal tract when administered orally and selective hepatic metabolization have been synthesised. In this review we analyzed published data on new fluoropyrimidines in an attempt to better define their role and to evaluate any significant improvement over fluorouracil.

Results

Athough no sure advantage over fluorouracil has been detected, interesting results have been reported for fluorouracil analogs with alternative routes of administration such as oral or intra-arterial chemotherapy.

Conclusions

Further studies, possibly randomized, should also measure quality of life and treatment-related costs in order to define their real advantage over fluorouracil in the palliation of advanced colorectal cancer.

Fluoropyrimidines in the Treatment of Advanced Neoplastic Diseases: Role and Advantages of UFT

The fluoropyrimidine antimetabolites were employed in a wide range of neoplastic diseases. In particular, 5-fluorouracil in association with other chemotherapeutic agents, or biochemical modulators was successfully used in the treatment of colorectal, gastric, breast, head and neck cancers. With this type of chemotherapy, a response rate ≤ 20% was obtained in gastrointestinal tumors, without a statistically significant impact on the overall survival.

UFT is a combination of tegafur an uracil, which has the important advantage of an improved oral bioavailability, if we compare it with 5-fluorouracil. Uracil, avoiding the fluoropyrimidine degradation inside the tumor cells, increases the permanence of the metabolically active fluropyrimidine into the target cell, so having an improvement in the therapeutic activity.

A very large spectrum of cancers were treated with this molecule. In particular, a response rate in the range of 20–40% was observed in the treatment of patients with metastatic colorectal cancer.

Phase III trials are ongoing to evaluate the advantage on 5-FU of this new fluoropyrimidine in terms of clinical efficacy, and quality of life, considering the possibility to administer it orally.

Chemotherapy for advanced gastric cancer

BACKGROUND

Gastric cancer is the fifth most common cancer worldwide. In "Western" countries, most people are either diagnosed at an advanced stage, or develop a relapse after surgery with curative intent. In people with advanced disease, significant benefits from targeted therapies are currently limited to HER-2 positive disease treated with trastuzumab, in combination with chemotherapy, in first-line. In second-line, ramucirumab, alone or in combination with paclitaxel, demonstrated significant survival benefits. Thus, systemic chemotherapy remains the mainstay of treatment for advanced gastric cancer. Uncertainty remains regarding the choice of the regimen.

OBJECTIVES

To assess the efficacy of chemotherapy versus best supportive care (BSC), combination versus single-agent chemotherapy and different chemotherapy combinations in advanced gastric cancer.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials, MEDLINE and Embase up to June 2016, reference lists of studies, and contacted pharmaceutical companies and experts to identify randomised controlled trials (RCTs).

SELECTION CRITERIA

We considered only RCTs on systemic, intravenous or oral chemotherapy versus BSC, combination versus single-agent chemotherapy and different chemotherapy regimens in advanced gastric cancer.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified studies and extracted data. A third investigator was consulted in case of disagreements. We contacted study authors to obtain missing information.

MAIN RESULTS

We included 64 RCTs, of which 60 RCTs (11,698 participants) provided data for the meta-analysis of overall survival. We found chemotherapy extends overall survival (OS) by approximately 6.7 months more than BSC (hazard ratio (HR) 0.3, 95% confidence intervals (CI) 0.24 to 0.55, 184 participants, three studies, moderate-quality evidence). Combination chemotherapy extends OS slightly (by an additional month) versus single-agent chemotherapy (HR 0.84, 95% CI 0.79 to 0.89, 4447 participants, 23 studies, moderate-quality evidence), which is partly counterbalanced by increased toxicity. The benefit of epirubicin in three-drug combinations, in which cisplatin is replaced by oxaliplatin and 5-FU is replaced by capecitabine is unknown.Irinotecan extends OS slightly (by an additional 1.6 months) versus non-irinotecan-containing regimens (HR 0.87, 95% CI 0.80 to 0.95, 2135 participants, 10 studies, high-quality evidence).Docetaxel extends OS slightly (just over one month) compared to non-docetaxel-containing regimens (HR 0.86, 95% CI 0.78 to 0.95, 2001 participants, eight studies, high-quality evidence). However, due to subgroup analyses, we are uncertain whether docetaxel-containing combinations (docetaxel added to a single-agent or two-drug combination) extends OS due to moderate-quality evidence (HR 0.80, 95% CI 0.71 to 0.91, 1466 participants, four studies, moderate-quality evidence). When another chemotherapy was replaced by docetaxel, there is probably little or no difference in OS (HR 1.05; 0.87 to 1.27, 479 participants, three studies, moderate-quality evidence). We found there is probably little or no difference in OS when comparing capecitabine versus 5-FU-containing regimens (HR 0.94, 95% CI 0.79 to 1.11, 732 participants, five studies, moderate-quality evidence) .Oxaliplatin may extend (by less than one month) OS versus cisplatin-containing regimens (HR 0.81, 95% CI 0.67 to 0.98, 1105 participants, five studies, low-quality evidence). We are uncertain whether taxane-platinum combinations with (versus without) fluoropyrimidines extend OS due to very low-quality evidence (HR 0.86, 95% CI 0.71 to 1.06, 482 participants, three studies, very low-quality evidence). S-1 regimens improve OS slightly (by less than an additional month) versus 5-FU-containing regimens (HR 0.91, 95% CI 0.83 to 1.00, 1793 participants, four studies, high-quality evidence), however since S-1 is used in different doses and schedules between Asian and non-Asian population, the applicability of this finding to individual populations is uncertain.

AUTHORS' CONCLUSIONS

Chemotherapy improves survival (by an additional 6.7 months) in comparison to BSC, and combination chemotherapy improves survival (by an additional month) compared to single-agent 5-FU. Testing all patients for HER-2 status may help to identify patients with HER-2-positive tumours, for whom, in the absence of contraindications, trastuzumab in combination with capecitabine or 5-FU in combination with cisplatin has been shown to be beneficial. For HER-2 negative people, all different two-and three-drug combinations including irinotecan, docetaxel, oxaliplatin or oral 5-FU prodrugs are valid treatment options for advanced gastric cancer, and consideration of the side effects of each regimen is essential in the treatment decision. Irinotecan-containing combinations and docetaxel-containing combinations (in which docetaxel was added to a single-agent or two-drug (platinum/5-FUcombination) show significant survival benefits in the comparisons studied above. Furthermore, docetaxel-containing three-drug regimens have increased response rates, but the advantages of the docetaxel-containing three-drug combinations (DCF, FLO-T) are counterbalanced by increased toxicity. Additionally, oxaliplatin-containing regimens demonstrated a benefit in OS as compared to the same regimen containing cisplatin, and there is a modest survival improvement of S-1 compared to 5-FU-containing regimens.Whether the survival benefit for three-drug combinations including cisplatin, 5-FU, and epirubicin as compared to the same regimen without epirubicin is still valid when second-line therapy is routinely administered and when cisplatin is replaced by oxaliplatin and 5-FU by capecitabine is questionable. Furthermore, the magnitude of the observed survival benefits for the three-drug regimens is not large enough to be clinically meaningful as defined recently by the American Society for Clinical Oncology (Ellis 2014). In contrast to the comparisons in which a survival benefit was observed by adding a third drug to a two-drug regimen at the cost of increased toxicity, the comparison of regimens in which another chemotherapy was replaced by irinotecan was associated with a survival benefit (of borderline statistical significance), but without increased toxicity. For this reason irinotecan/5-FU-containing combinations are an attractive option for first-line treatment. Although they need to be interpreted with caution, subgroup analyses of one study suggest that elderly people have a greater benefit form oxaliplatin, as compared to cisplatin-based regimens, and that people with locally advanced disease or younger than 65 years might benefit more from a three-drug regimen including 5-FU, docetaxel, and oxaliplatin as compared to a two-drug combination of 5-FU and oxaliplatin, a hypothesis that needs further confirmation. For people with good performance status, the benefit of second-line chemotherapy has been established in several RCTs.

A pilot study of mRNA expressions of 5-fluorouracil pathway genes in peripheral blood mononuclear cells and tumor tissues in patients with lung adenocarcinoma

To assess whether early lung cancer prediction might be informed by an mRNA assay for 5-fluorouracil pathway genes in peripheral blood mononuclear cells (PBMNCs), we examined specimens taken from 51 adenocarcinoma patients and 38 controls (including six patients with benign tumors). PBMNCs and tumor-tissue specimens were taken for measurement of the mRNAs of various 5-fluorouracil pathway genes [thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), thymidine phosphorylase (TP), and orotate phosphoribosyl transferase (OPRT)]. By quantitative RT-PCR, all four mRNAs were detected in both PBMNCs and tumor tissues. In PBMNCs, TS mRNA/GAPDH mRNA levels were significantly higher in adenocarcinoma patients than in the controls, and significantly higher for pathological stages 2-4 and lymph-node involvement pN1-pN3 than for pathological stage 1 and pN0, respectively. No correlation between PBMNCs and tumor-tissue specimens was found for the level of any mRNA. Thus, the measurement of TS mRNA in PBMNCs might aid the diagnosis of lung adenocarcinoma.

Chemotherapy for advanced gastric cancer

BACKGROUND

Gastric cancer currently ranks second in global cancer mortality. Most patients are either diagnosed at an advanced stage, or develop a relapse after surgery with curative intent. Apart from supportive care and palliative radiation to localized (e.g. bone) metastasis, systemic chemotherapy is the only treatment option available in this situation.

OBJECTIVES

To assess the efficacy of chemotherapy versus best supportive care, combination versus single agent chemotherapy and different combination chemotherapy regimens in advanced gastric cancer.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE up to March 2009, reference lists of studies, and contacted pharmaceutical companies and national and international experts.

SELECTION CRITERIA

Randomised controlled trials on systemic intravenous chemotherapy versus best supportive care, combination versus single agent chemotherapy and different combination chemotherapies in advanced gastric cancer.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data. A third investigator was consulted in case of disagreements. We contacted study authors to obtain missing information.

MAIN RESULTS

Thirty five trials, with a total of 5726 patients, have been included in the meta-analysis of overall survival. The comparison of chemotherapy versus best supportive care consistently demonstrated a significant benefit in overall survival in favour of the group receiving chemotherapy (hazard ratios (HR) 0.37; 95% confidence intervals (CI) 0.24 to 0.55, 184 participants). The comparison of combination versus single-agent chemotherapy provides evidence for a survival benefit in favour of combination chemotherapy (HR 0.82; 95% CI 0.74 to 0.90, 1914 participants). The price of this benefit is increased toxicity as a result of combination chemotherapy. When comparing 5-FU/cisplatin-containing combination therapy regimens with versus without anthracyclines (HR 0.77; 95% CI 0.62 to 0.95, 501 participants) and 5-FU/anthracycline-containing combinations with versus without cisplatin (HR 0.82; 95% CI 0.73 to 0.92, 1147 participants) there was a significant survival benefit for regimens including 5-FU, anthracyclines and cisplatin. Both the comparison of irinotecan versus non-irinotecan (HR 0.86; 95% CI 0.73 to 1.02, 639 participants) and docetaxel versus non-docetaxel containing regimens (HR 0.93; 95% CI 0.75 to 1.15, 805 participants) show non-significant overall survival benefits in favour of the irinotecan and docetaxel-containing regimens.

AUTHORS' CONCLUSIONS

Chemotherapy significantly improves survival in comparison to best supportive care. In addition, combination chemotherapy improves survival compared to single-agent 5-FU. All patients should be tested for their HER-2 status and trastuzumab should be added to a standard fluoropyrimidine/cisplatin regimen in patients with HER-2 positive tumours. Two and three-drug regimens including 5-FU, cisplatin, with or without an anthracycline, as well as irinotecan or docetaxel-containing regimens are reasonable treatment options for HER-2 negative patients.

UFT (tegafur and uracil) as postoperative adjuvant chemotherapy for solid tumors (carcinoma of the lung, stomach, colon/rectum, and breast): clinical evidence, mechanism of action, and future direction

UFT (tegafur and uracil) is an oral anticancer drug that has been developed in Japan. Owing to its mild toxicity profile, UFT can be suitable in an adjuvant setting following a complete tumor resection, whereas its direct antitumor effect achieved may be insufficient for advanced unresectable disease. Therefore, a variety of adjuvant chemotherapy trials with UFT have been conducted, and results of well-designed randomized controlled trials have recently shown a survival benefit of postoperative UFT treatment in resected lung, gastric, colorectal, and breast cancer. In the present article, postoperative adjuvant trials with UFT-containing chemotherapy are reviewed, and the mechanism of action and future directions are also discussed.

Synergistic antitumor activity of capecitabine in combination with irinotecan

5-Fluorouracil (5-FU) and capecitabine alone and in combination with irinotecan/oxaliplatin are clinically active in the treatment of colorectal and other solid tumors. Studies of the antitumor activity and toxicity of capecitabine or irinotecan alone and in combination with each other, were compared with 5-FU and raltitrexed in human tumor xenografts of colorectal and squamous cell carcinoma of the head and neck using clinically relevant schedules. Antitumor activity and toxicity were evaluated in nude mice bearing human colon carcinomas of HCT-8 and HT-29 and in head and neck squamous cell carcinomas of A253 and FaDu xenografts using the maximum tolerable dose of single-agent capecitabine, 5-FU, or raltitrexed, or each of the drugs in combination with irinotecan. Mice were treated with capecitabine and irinotecan alone or in combination using 2 different schedules: (1) capecitabine orally once a day for 7 days and a single dose of irinotecan (50 mg/kg intravenously [I.V.]), with each drug alone or in combination, and (2) capecitabine orally 5 days a week for 3 weeks and irinotecan 50 mg/kg (I.V. injection) once a week for 3 weeks, with each drug alone or in combination. For comparative purposes, the antitumor activity of single-agent capecitabine, 5-FU, or raltitrexed, or each drug in combination with irinotecan was carried out at its maximum tolerated dose (MTD) using a 3-week schedule. Results indicated that HT-29 and A253 xenografts were de novo resistant (no cure) to capecitabine and irinotecan alone at the MTD, whereas HCT-8 and FaDu xenografts were relatively more sensitive, yielding 10%-20% cures. The combination of irinotecan/capecitabine was much more active than either drug alone against all 4 tumor models. The cure rates were increased from 0 to 20% in A253 and HT-29 xenografts and from 10%-20% to 80%-100% in HCT-8 and FaDu tumor xenografts, respectively. Irinotecan/capecitabine had clear advantage over irinotecan/5-FU and irinotecan/raltitrexed in efficacy and selectivity in that they were more active and less toxic. The extent of synergy with irinotecan/capecitabine appears to be tumor-dependent and independent of the status of p53 expression. The potential impact of the preclinical results on clinical practice for the use of these drugs in combination needs clinical validation.

Chemotherapy for advanced gastric cancer

BACKGROUND

Gastric cancer currently ranks second in global cancer mortality. Most patients are either diagnosed at an advanced stage, or develop a relapse after apparently curative operation. Apart from supportive measures, systemic chemotherapy is the only treatment option available in this situation.

OBJECTIVES

To assess the effect of chemotherapy versus best supportive care, combination versus single agent chemotherapy and different combination chemotherapy regimens in advanced gastric cancer.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 1, 2004), MEDLINE and EMBASE up to February 2004 and reference lists of articles. We also contacted pharmaceutical companies as well as national and international experts.

SELECTION CRITERIA

Randomised controlled trials on systemic intravenous chemotherapy versus best supportive care, combination versus single agent chemotherapy and different combination chemotherapies in advanced gastric cancer.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data. A third investigator was consulted in case of disagreements. We contacted study authors to obtain missing information.

MAIN RESULTS

Chemotherapy versus best supportive care consistently demonstrated a significant benefit in terms of overall survival in favour of the group receiving chemotherapy (Hazard Ratios (HR) 0.39; 95% confidence intervals (CI) 0.28 to 0.52). Combination versus single-agent chemotherapy provides evidence for a survival benefit in favour of combination chemotherapy (HR 0.85; 95% CI 0.76 to 0.96). Numbers included in these comparisons were 184 and 1338 participants respectively. This benefit is achieved at the price of increased toxicity in the combination chemotherapy arms. When comparing 5-FU/cisplatin-containing combination therapy regimens with anthracyclines versus those without anthracyclines (HR 0.77; 95% CI 0.62 to 0.95 based on 501 participants) and 5-FU/anthracycline-containing combinations with cisplatin versus those without cisplatin (HR 0.83; 95% CI 0.76 to 0.91 based on 1147 participants), there was a significant survival benefit for regimens including 5-FU, anthracyclines and cisplatin.

AUTHORS' CONCLUSIONS

Chemotherapy significantly improves survival in comparison to best supportive care. In addition, combination chemotherapy improves survival compared to single-agent 5-FU, but the effect size is much smaller. Among the combination chemotherapy regimens studied, best survival results are achieved with regimens containing 5-FU, anthracyclines and cisplatin. In this category, ECF (epirubicin, cisplatin and continuous infusion 5-FU) is tolerated best.

The role of uracil-tegafur (UFT) in elderly patients with colorectal cancer

5-Fluorouracil (5-FU) administered in several schedules since its introduction in 1957 continues to be an integral part of standard first-line therapy for colorectal cancer. Continuous intravenous (i.v.) infusion appears to yield improved response rate and overall survival, with fewer adverse effects compared with i.v. bolus dosing. However, these protracted infusions require portable infusion pumps and central venous lines, which are associated with complications (i.e. increased risk of infection and clotting and/or dislodgement of the catheter, increased risk of venous thrombosis). Colorectal carcinoma is the second cause of death for tumour after lung cancer. About 70% of cases occur over 65 years and 50% or more affects people over 70. In clinical research age was a common exclusion criteria and little information is available about the efficacy, safety and toxicity of chemotherapy in elderly patients because few studies focused on the treatment of cancer in that part of population. The goal of this article is to review the literature concerning the treatment of elderly patients with UFT, an orally administered dihydropyrimidine dehydrogenase (DPD) inhibitory fluoropyrimidine.

Comparison of the efficacy, toxicity, and pharmacokinetics of a uracil/tegafur (UFT) plus oral leucovorin (LV) regimen between Japanese and American patients with advanced colorectal cancer: joint United States and Japan study of UFT/LV

PURPOSE

To compare the efficacy, toxicities, and pharmacokinetics of an oral regimen consisting of uracil/tegafur (UFT) and leucovorin (LV) between Japanese patients and patients in the United States with previously untreated metastatic colorectal cancer.

PATIENTS AND METHODS

Forty-four Japanese patients and 45 patients in the United States were enrolled in concurrent nonrandomized phase II trials. UFT 300 mg/m2/d and leucovorin 75 mg/d were administered orally for 28 days followed by a 7-day rest period. The total daily dose of each drug was divided into three equal doses. Treatment was repeated every 5 weeks until disease progression. Blood samples for the pharmacokinetic study were obtained after the initial dose on day 1 of the first course.

RESULTS

The response rate for the Japanese patients and the patients in the United States was 36.4% (95% CI, 22.4% to 52.2%) and 34.1% (95% CI, 20.5% to 49.9%), respectively. The only major toxicity was diarrhea, and other toxicities were mild in both populations. The incidence of grade 3 or higher diarrhea in the Japanese and Americans was 9% and 22%, respectively. Although the area under the curve and maximum concentration of fluorouracil were found to be slightly higher in the Japanese patients than the patients in the United States, and area under the curve-adjusted body surface area appeared to be comparable between the two groups.

CONCLUSION

The efficacy and pharmacokinetic parameters of UFT and LV are comparable in Japanese and American patients; however, a difference in toxicity profile, specifically diarrhea, was noted. This oral regimen of UFT and LV is considered to have similar activity against metastatic colorectal cancer and to have acceptable toxicity in patients in both countries.

Adjuvant immunochemotherapy with oral Tegafur/Uracil plus PSK in patients with stage II or III colorectal cancer: a randomised controlled study

Intravenous fluorouracil and leucovorin is the standard adjuvant treatment for stage III colon cancer. However, oral adjuvant chemotherapy is attractive because it has low toxicity and greater convenience. We investigated the benefits of oral protein-bound polysaccharide K (PSK) with tegafur/uracil (UFT) as an adjuvant in stage II and III colorectal cancer. Patients were assigned to groups that received either 3 g PSK plus 300 mg UFT, or 300 mg UFT alone orally each day for a 2-year period following intravenous mitomycin C. Of 207 registered patients, 205 with stage II (n=123) or III (n=82) were analysed. The 5-year disease-free survival was 73.0% (95% CI 65.6-80.4%) with PSK (n=137) and 58.8% (95% CI 47.1-70.5%) in the controls (n=68) (P=0.016). Polysaccharide K reduced the recurrence by 43.6% (95% CI 4.5-66.7%) and mortality by 40.2% (95% CI -12.5 to 68.3%). The 5-year survival was 81.8% (95% CI 75.3-88.2%) in the PSK group and 72.1% (95% CI 61.4-82.7%) in the control group (P=0.056). In stage III patients, disease-free and overall survivals in patients receiving PSK were increased significantly: 60.0% (95% CI 47.1-72.9%) and 74.6% (95% CI 63.0-86.1%) in the PSK group as compared with 32.1% (95% CI 14.8-49.4%) and 46.4% (95% CI 28.0-64.9%) in the controls (P=0.002 and 0.003, respectively). Polysaccharide K prevented recurrence, particularly lung metastases (P=0.02; odds ratio 0.27; 95% CI 0.09-0.77). In the models, the presence of regional metastases (relative risk, 2.973; 95% CI 1.712-5.165; P<0.001), omission of PSK (relative risk, 2.106; 95% CI 1.221-3.633; P=0.007), and higher primary tumour (relative risk, 4.398; 95% CI 1.017-19.014; P=0.047) were each significant indicators of recurrence. Adverse effects were mild and compliance was good. Oral PSK with UFT reduced recurrence in stage II and III colorectal cancer, and increased survival in stage III.

Phase I trial of UFT/leucovorin and irinotecan in patients with advanced cancer

UFT (BMS-200604, Uftoral) is an oral fluoropyrimidine that combines uracil and the 5-fluorouracil (5-FU) prodrug, ftorafur, in a 4:1 molar ratio with single-agent activity in breast and gastrointestinal cancers. In vitro studies have shown that irinotecan downregulates thymidylate synthase (TS) expression in tumour cells, leading to synergy between irinotecan and 5-FU that is maximal when irinotecan is given 24 h prior to 5-FU. Given this observed synergy and the confirmatory clinical activity of combination therapy with 5-FU, leucovorin (LV) and irinotecan, we performed a phase I trial to determine the maximum tolerated doses (MTD) of UFT, LV, and irinotecan. Treatment consisted of irinotecan administered as a 90-min intravenous (i.v.) infusion on day 1 followed by twice daily oral UFT/LV on days 2-15, repeated every 21 days. Initial doses were irinotecan 200 mg/m(2) and UFT 200 mg/m(2)/day, with LV dose fixed at 60 mg/day. 31 patients received a total of 130 cycles of UFT/LV and irinotecan. 3 of 9 patients experienced grade 3/4 diarrhoea at the highest dose level of irinotecan 310 mg/m(2) and UFT 300 mg/m(2)/day. Other toxicities included neutropenia, anaemia, alopecia, nausea/vomiting and fatigue. Further dose escalation was not pursued since this level of toxicity was appropriate for future phase II study. One patient with colorectal cancer experienced a partial response and 9 patients with non-small cell lung, colorectal and gastro-oesophageal junction carcinomas had disease stabilisation lasting 4-26 (median 6) cycles. Methylenetetrahydrofolate reductase (MTHFR) C677T genotype was analysed in peripheral mononuclear cells (PMNs) obtained from 24 patients. 2 patients had the homozygous TT polymorphism and 1 of them had grade 3 diarrhoea at the first dose level. Irinotecan on day 1 followed by a 14-day course of oral UFT/LV beginning on day 2 is well tolerated, and suitable for testing in several tumour types. Doses recommended for further study on this schedule are irinotecan 310 mg/m(2) and UFT 300 mg/m(2)/day, with LV 60 mg/day.

Clinical studies of three oral prodrugs of 5-fluorouracil (capecitabine, UFT, S-1): a review

Although 5-fluorouracil (5-FU) was first introduced in 1957, it remains an essential part of the treatment of a wide range of solid tumors. 5-FU has antitumor activity against epithelial malignancies arising in the gastrointestinal tract and breast as well as the head and neck, with single-agent response rates of only 10%-30%. Although 5-FU is still the most widely prescribed agent for the treatment of colorectal cancer, less than one-third of patients achieve objective responses. Recent research has focused on the biomodulation of 5-FU to improve the cytotoxicity and therapeutic effectiveness of this drug in the treatment of advanced disease. As all the anticancer agents, 5-FU leads to several toxicities. The toxicity profile of 5-FU is schedule dependent. Myelotoxicity is the major toxic effect in patients receiving bolus doses. Hand-foot syndrome (palmar-plantar erythrodysesthesia), stomatitis, and neuro- and cardiotoxicities are associated with continuous infusions. Other adverse effects associated with both bolus-dose and continuous-infusion regimens include nausea and vomiting, diarrhea, alopecia, and dermatitis. All these reasons explain the need for more effective and less toxic fluoropyrimidines. In the first part of this review, we briefly present the metabolic pathways of 5-FU responsible for the efficacy and toxicity of this drug. This knowledge is also necessary to understand the target(s) of biomodulation. The second part is devoted to a review of the literature on three recent prodrugs of 5-FU, i.e., capecitabine, UFT (ftorafur [FTO] plus uracil), and S-1 (FTO plus 5-chloro-2,4-dihydroxypyridine plus potassium oxonate). The pharmacological principles that have influenced the development of these new drugs and our current knowledge of the clinical pharmacology of these new agents, focusing on antitumor activity and toxicity, are presented. The literature was analyzed until March 2002. This review is intended to be as exhaustive as possible since it was conceived as a work tool for readers wanting to go further.

Multicenter phase III study of uracil/tegafur and oral leucovorin versus fluorouracil and leucovorin in patients with previously untreated metastatic colorectal cancer

PURPOSE

This phase III study was designed to demonstrate equivalence in survival of oral uracil/tegafur (UFT) and oral leucovorin (LV) to conventional intravenous (IV) fluorouracil (5-FU) and LV in previously untreated metastatic colorectal carcinoma. Safety was also compared.

PATIENTS AND METHODS

Eight hundred sixteen patients were randomized to receive either UFT (300 mg/m(2)/d) and LV (75 or 90 mg/d) for 28 days every 35 days or IV bolus 5-FU (425 mg/m(2)/d) and LV (20 mg/m(2)/d) for 5 days every 28 days.

RESULTS

UFT/LV produced survival comparable to the IV 5-FU/LV regimen. Median survival was 12.4 months (95% confidence interval [CI], 11.2 to 13.6 months) with UFT/LV and 13.4 months (95% CI, 11.6 to 15.4 months) with 5-FU/LV (P =.630). The hazard ratio for survival was 0.964 (95.6% CI, 0.826 to 1.125), supporting equivalent survival. The overall response rate did not differ between treatment arms (UFT/LV, 11.7%; 5-FU/LV, 14.5%; P =.232). Median time to progression favored 5-FU/LV (UFT/LV, 3.5 months; 5-FU/LV, 3.8 months; P =.011), but tumor assessment schedules differed between arms. UFT/LV significantly improved safety compared with 5-FU/LV. Diarrhea, nausea and vomiting, and stomatitis and mucositis were significantly less frequent with UFT/LV, as was myelosuppression. Patients treated with UFT/LV had fewer episodes of febrile neutropenia (P <.001) and documented infections (P <.05). Increased bilirubin, without other liver function abnormalities, was observed more often with UFT/LV (P <.001). Concomitant medications were more frequent with 5-FU/LV, including use of antibiotics, growth factors, and antiemetics.

CONCLUSION

UFT/LV provided a safer, more convenient oral alternative to a standard bolus IV 5-FU/LV regimen for metastatic colorectal cancer while producing equivalent survival.

Randomized comparative study of tegafur/uracil and oral leucovorin versus parenteral fluorouracil and leucovorin in patients with previously untreated metastatic colorectal cancer

PURPOSE

This phase III study compared the time to progression (TTP) of an oral regimen of dihydropyrimidine dehydrogenase inhibitory fluoropyrimidine composed of a fixed combination of tegafur and uracil in a 1:4 molar ratio (UFT) and leucovorin (LV) to intravenous (IV) fluorouracil (5-FU) and LV in previously untreated metastatic colorectal carcinoma (CRC) patients. Secondary end points were survival, tumor response, safety, and quality of life.

PATIENTS AND METHODS

Between May 1996 and July 1997, 380 patients were randomized to receive either UFT (300 mg/m(2)/d) and LV (90 mg/d), administered for 28 days every 35 days, or 5-FU (425 mg/m(2)/d) and LV (20 mg/m(2)/d), given IV for 5 days every 35 days.

RESULTS

No statistically significant difference in TTP was observed between treatments. With 320 events assessed, the median TTP was 3.4 months (95% Confidence interval [CI], 2.6 to 3.8) on UFT/LV and 3.3 months (95% CI, 2.5 to 3.7) on 5-FU/LV (P =.591, stratified log-rank test). There were no statistically significant differences in survival, tumor response, duration of response, and time to response. Substantial safety benefits were observed in patients treated with UFT/LV. They experienced significantly less stomatitis/mucositis (P <.001) and myelosuppression, resulting in fewer episodes of febrile neutropenia (P <.001) and less documented infection (P =.04). Concomitant medication usage was significantly greater on 5-FU/LV (P =.010). With respect to quality of life, after correcting for baseline imbalances, there were no significant differences between treatments for any scale, except diarrhea.

CONCLUSION

The oral UFT/LV regimen failed to achieve improved TTP; however, the study confirms significant safety improvements compared with bolus IV 5-FU/LV for the first-line treatment of metastatic CRC.

Oral tegafur/uracil

Tegafur is a prodrug of the antineoplastic agent fluorouracil, and is administered in a 1:4 molar ratio with the fluorouracil modulator uracil. Oral tegafur/uracil 300 mg/m(2)/day plus calcium folinate 75 or 90 mg/day for 28 days every 35 days was as effective as intravenous (IV) fluorouracil 425 mg/m(2)/day plus folinic acid 20 mg/m(2)/day for 5 days every 28 or 35 days in the treatment of patients with metastatic colorectal cancer in two large, randomised, nonblind, multicentre trials (n = 816 and 380). Median survival time among patients treated with tegafur/ uracil or fluorouracil was approximately 12 months in both trials. Results from both trials also demonstrated no significant between-group differences in overall response rates among patients treated with oral tegafur/uracil (12 and 11%) or IV fluorouracil (15 and 9%). In elderly patients (aged > or = 70 years) with metastatic colorectal cancer, results from small noncomparative studies showed that treatment with oral tegafur/uracil afforded overall response rates of 12.5 to 29% and was well tolerated. During preoperative treatment with oral tegafur/uracil plus calcium folinate as an adjunct to radiotherapy in patients with stage II or III rectal cancer, the maximum tolerated dosage of tegafur/uracil was 350 mg/m(2)/day (administered 5 days per week for 5 weeks). Among the 15 patients who were followed for 5 to 8 months, three had a complete response to treatment. Treatment with tegafur/uracil was also given postoperatively. The most common adverse events associated with oral tegafur/uracil were anaemia, nausea/vomiting, diarrhoea, thrombocytopenia, mucositis, neutropenia, asthenia, anorexia and abdominal pain. Oral tegafur/uracil was associated with a significantly more favourable tolerability profile than IV fluorouracil in the two large randomised trials. In particular, stomatitis and most adverse haematological events were less frequent.

UFT and leucovorin in first-line chemotherapy for patients with metastatic gastric cancer. An Early Clinical Studies Group (ECSG)/European Organization for Research Treatment of Cancer (EORTC) phase II trial

A phase II study was performed to evaluate 1-(2-tetrahydrofuryl)-5-fluorouracil and uracil (UFT) and leucovorin as first-line chemotherapy in European patients with advanced gastric cancer. From 38 patients, 25 were evaluable for response and 36 for toxicity. Patients received UFT at 300 mg/m(2)/day for 28 days, every 35 days and leucovorin at 90 mg/day on an identical schedule. Overall response rate was 10.5% (95% confidence interval (CI): 3.7-22.5%) in intent-to-treat analysis and 16% (95% CI: 5.7-33%) in evaluable patients. Grade 3-4 common toxicity criteria (CTC) toxicities were diarrhoea (28%; 10/36), nausea (11%; 4/36), vomiting (8%; 3/36) and asthenia (11%; 4/36). 23 patients in 44% (42/96) of the courses had to skip days of treatment due to toxicity or to non-compliance. In conclusion, UFT+leucovorin has a definitive, but low, efficacy in advanced gastric cancer patients. Toxicities were mainly gastrointestinal and treatment needs to be withheld if grade 2 diarrhoea occurs.

The oral fluorinated pyrimidines

The fluorinated pyrimidines have played a major role in the treatment of many common tumors since 5-fluorouracil (5FU) was first introduced. Studies of the cellular and clinical pharmacology of 5FU have led to an improved understanding of the mechanisms of action of this agent. This knowledge has allowed the optimal and rational development of fluoropyrimidine therapy, with significant therapeutic advances in recent years. Efforts to improve the therapeutic index of 5FU have included alteration of schedule, and the addition of biochemical modulators such as folinic acid. Although protracted continuous infusion of 5FU has led to better response rates and decreased toxicity, the administration of 5FU by protracted infusion is not only costly, but also inconvenient to the patient. Furthermore it is often associated with infectious and thrombotic complications related to the required indwelling intravenous catheter. Protracted oral administration is a rational route for administering 5FU, being preferred by the patient and the pharmaco-economist. The unpredictable and low oral bioavailability of 5FU initially discouraged this form of treatment. This problem has now been overcome by the new generation of oral fluoropyrimidines. Two main strategies have been pursued: 1) The administration of an inactive prodrug of 5FU, which is absorbed intact, and subsequently converted to 5FU. Capecitabine is converted to 5FU by a 3 step enzymatic process. 2) The administration of 5FU with an inhibitor of dihydropyrimidine dehydrogenase (DPD) to minimise the erratic absorption and variable clearance of 5FU: the preparations UFT, S1, and ethinyluracil/5FU contain an oral fluoropyrimidine co-administered orally with inhibitors of this enzyme. The development and characteristics of these agents are discussed.

Dual modulation of UFT with leucovorin and hydroxyurea in metastatic colorectal cancer

The aim of the study was to investigate the possibility of dual modulation of UFT with leucovorin and hydroxyurea in a phase II trial of metastatic colorectal cancer. A total of 77 patients with measurable disease were included. UFT (300 mg/m2) was given with a fixed dose of 1-leucovorin (22.5 mg daily) and hydroxyurea (0.5 g daily) for 28 days followed by a 7 days' rest period. Treatment continued until progression or unacceptable toxicity. Sixty-three patients were evaluable for response. One patient (1.6%) had a complete remission and 13 (20.6%) a partial response for an overall response rate of 22.2%. The treatment was well tolerated. No significant bone marrow depression occurred. Grade 2 gastrointestinal toxicity was recorded in 28.5% of the patients, and grade 3 in 12.9%. The median time to progression was 6.8 months and the median crude survival was 11 months. In conclusion, hydroxyurea did not appear to increase either the response rate or the toxicity. Phase III trials along the same line cannot be recommended.

Tegafur and uracil plus leucovorin in advanced colorectal cancer: a phase II trial

The objective of this study was to evaluate the activity and toxicity of tegafur and uracil (UFT; 1:4 molar ratio) plus leucovorin (LV) in patients with advanced colorectal cancer. One hundred forty-one patients were entered into the study. The treatment schedule consisted of UFT 300 mg/m2/day (in three divided doses) plus oral LV 150 mg/day (50 mg t.i.d.) over 28 days. The treatment cycle was repeated every 5 weeks until progression or unacceptable toxicity was observed. The treatment was interrupted if grade 3/4 toxicity appeared and was resumed at the same dosage on recovery. One hundred thirty-six patients were evaluable for response and 141 were evaluable for toxicity. The response rate was 19.9% (95% confidence interval: 12%-28%). The total number of patients without progression (objective response + stable disease) was 76 (55.9%). The median time to progression was 5.6 months, and the overall survival was 11.6 months. The toxicity profile was low, with 11% of patients experiencing grade 3/4 nausea and vomiting, while 17% had grade 3/4 diarrhea. Oral administration of UFT modulated with LV is a comfortable regimen of chemotherapy for patients with advanced colorectal cancer.

Phase I assessment of the pharmacokinetics, metabolism, and safety of emitefur in patients with refractory solid tumors

PURPOSE

To determine the toxicities, dose-limiting toxicities (DLT), maximum-tolerated dose, and pharmacokinetic profile of emitefur (BOF-A2) in patients with advanced solid tumors.

METHODS

This was a phase I dose-escalating trial in which cohorts of patients received BOF-A2 (cohort 1, 300 mg/m(2) orally [PO] tid; cohort 2, 200 mg/m(2) PO tid; cohort 3, 200 mg/m(2) bid; and cohort 4, 250 mg/m(2) bid) for 14 consecutive days followed by 1 week of rest (cycle 1). Pharmacokinetics, toxicity, and tumor response were monitored.

RESULTS

Nineteen patients received 110 cycles (three patients in cohort 1, three patients in cohort 2, 10 patients in cohort 3, and three patients in cohort 4). DLT (grade 3 stomatitis, diarrhea, leukopenia) was observed in cohorts 1, 2, and 4. Pharmacokinetics indicated that prolonged systemic expression of fluorouracil (5-FU) is maintained after administration of BOF-A2 at a dose of 200 mg bid for 14 days. The mean steady-state concentration of plasma 5-FU was > or = 24 ng/mL, which was 184-fold greater than the minimum effective cytotoxic concentration in vitro. Lack of variation of 5-FU trough levels within a day at steady-state indicates suppression of circadian variation. One patient in cohort 3 achieved a partial response and five patients maintained stable disease in excess of 6 months.

CONCLUSION

BOF-A2 at a dose of 200 mg PO bid for 14 days followed by 7 days of rest is well tolerated. Prolonged exposure to 5-FU above the predicted preclinical minimum effective concentration is maintained, without evidence of circadian variation. Furthermore, evidence of antitumor activity is suggested.

Synergistic antitumoral activity of combined UFT, folinic acid and oxaliplatin against human colorectal HT29 cell xenografts in athymic nude mice

This study was designed to assess the inhibition of tumor growth by oxaliplatin combined with UFT and folinic acid (FA). Growth inhibition was studied in nude mice transplanted with human colorectal HT29 tumor cell xenografts and treated for 28 days with oral UFT (20 mg/kg/day) and FA (4 mg/kg/day), i.p. oxaliplatin (10 mg/kg on day 1) or a combination of oxaliplatin, UFT and FA, or else not treated (controls). Tumor surface area and weight were recorded twice a week, and mice were sacrificed at day 28. Two separate experiments were performed for each group of 25 mice. At day 28, mean tumor weights (g) were 2.89+/-0.22 (controls), 2.03+/-0.14 (oxaliplatin), 2.02+/-0.21 (UFT/FA) and 1.23+/-0.17 (oxaliplatin+UFT/FA). For the three treatment groups, tumor weight decreases were 30.1% (p<0.05), 29.9% (p<0.05) and 57.5% (p<0.001), respectively. Combined treatment (UFT/FA+oxaliplatin) reduced tumor weight by 39% compared to oxaliplatin alone (p<0.05) or UFT/FA (p<0.05). These results demonstrate the synergistic effect of the combination of oxaliplatin, UFT and FA in this HT29 cell xenograft model, and warrant further investigations in patients with metastatic colorectal cancer.

Phase II study of S-1, a novel oral fluorophyrimidine derivative, in patients with metastatic colorectal carcinoma. S-1 Cooperative Colorectal Carcinoma Study Group

This study set out to evaluate, in patients with metastatic colorectal carcinoma, the efficacy and toxicity of S-1, which contains tegafur, 5-chloro-2,4-dihydroxypyridine (CDHP) and potassium oxonate, based on a biochemical modulation of 5-fluorouracil (5-FU) targeted at inhibition of dihydropyrimidine dehydrogenase (DPD). Sixty-three patients with measurable metastatic colorectal carcinoma were enrolled into the study. None of the patients had received prior chemotherapy except for adjuvant setting. S-1 was administered orally twice daily at a standard dose of 80 mg m(-2) day(-1) for 28 days followed by a 14-day rest. This agent is continued until disease progression, unaccepted toxicity, or patient refusal. Twenty-two (35%) of the 62 eligible patients achieved PR with a 95% confidence interval of 25-48%. Five of the 10 patients with a history of adjuvant chemotherapy achieved partial remission. The median survival time was 12 months. Major adverse reactions included myelosuppressive and gastrointestinal toxicities, though their incidence of grade 3 or 4 being 13% in neutropenia and less than 10% in the others. None of the 53 patients treated as outpatients required hospitalization due to adverse reactions: These results suggest that S-1 achieves similar responses to those of infusional 5-FU plus leucovorin and shows the potential of another biochemical modulation with easily manageable toxicity.

Recent developments in oral chemotherapy options for gastric carcinoma

The incidence of carcinoma of the stomach is low in the United States, Canada, and Australia but is a significant health problem in Asia, South America, Eastern Europe, and countries of the previous Soviet Union. For patients with advanced disease, chemotherapy remains palliative. With the increasing emphasis on patients' quality of life, convenience, and cost containment, oral chemotherapy has come into increasing focus. We review oral chemotherapy agents for use in patients with advanced gastric carcinoma. Etoposide, given intravenously, has modest activity in gastric carcinoma. We studied oral etoposide, which was administered to 28 patients at the starting dose of 50 mg/m2/day for 21 days followed by a 7-day rest period. Five patients achieved a partial response and 4 patients achieved a minor response. The drug was well tolerated. Common toxicities included myelosuppression, alopecia, and nausea. Oral etoposide thus shows evidence of modest activity against gastric carcinoma. In Japan, considerable advances have been made in the oral chemotherapy of gastric carcinoma. The second generation fluorouracil prodrug tegafur/uracil (UFT) has been extensively evaluated in Japan, Korea, and Spain. Data predominantly from Japan indicate that tegafur/uracil has a response rate of approximately 20% in treatment naive patients with advanced gastric carcinoma. When combined with other active agents, tegafur/uracil has a response rate of more than 30% in these patients. The available data also suggest that tegafur/uracil is well tolerated and that patient acceptance is high. In conclusion, future clinical research is likely to focus on the development of convenient outpatient regimens with efficacy equal to that of intravenous regimens.

Oral fluoropyrimidines: a closer look at their toxicities

Patient preferences, quality of life issues, and economic considerations are driving the development of orally administered chemotherapy. Oral fluorinated pyrimidines, which have been used in Japan, are attracting increasing interest as a means to provide convenient, less toxic treatment without compromising efficacy. The oral fluoropyrimidines provide prolonged 5-fluorouracil (5-FU) exposure at lower peak concentrations than those observed with bolus intravenous administration. Moreover, depending on the dose schedule, the pharmacokinetics of the oral fluoropyrimidines may mimic the pharmacokinetics of continuous-infusion 5-FU. This review focuses on the toxicity profiles of five emerging oral fluoropyrimidine antineoplastic drugs: combined uracil and tegafur (UFT), capecitabine, eniluracil, S-1, and emitefur (BOF-A2). Different patterns of toxicities emerge from an analysis of the clinical trials of these agents relative to 5-FU administered as an intermittent intravenous bolus or as continuous infusion. The results of ongoing phase III trials comparing the oral fluoropyrimidines with conventional regimens of 5-FU plus leucovorin and 5-FU by continuous intravenous infusion are necessary before their therapeutic role in the management of colorectal carcinoma can be defined.

Phase II study of radiochemotherapy with UFT and low-dose oral leucovorin in patients with unresectable rectal cancer

PURPOSE

To determine the activity and evaluate the toxicity of uracil and tegafur in a 4:1 molar concentration (UFT) plus low-dose leucovorin administered concomitantly with pelvic irradiation in patients with unresectable or recurrent rectal cancer.

METHODS AND MATERIALS

Thirty-five patients (22 with primary unresectable tumors and 13 with locally recurrent tumors) were enrolled in the trial. Thirty-five patients were evaluable for toxicity and 32 of these were evaluable for clinical response. Patients received 300 mg/m2/day UFT and 30 mg/day leucovorin on days 8-35 concomitantly with pelvic radiotherapy, to a total dose of 45 Gy.

RESULTS

Eight of the 35 (23%) patients developed Grade 3 diarrhea and were treated with radiotherapy alone after this event. Of the 22 patients with unresectable primary tumors, 17 underwent surgery, and resection was feasible in 15 cases (88%). Of the 32 patients evaluable for clinical response, 4 (13%) had a complete clinical response (CR) and 22 (69%) a partial response (PR). A complete pathologic response was observed in 3 cases (18%) and, a PR in 11 cases (65%).

CONCLUSION

The response rates achieved with this schedule seem comparable to those obtained with 5-FU and radiotherapy. These results warrant further evaluation of this combination in patients with unresectable or locally advanced tumors.

Chemosensitivity of micrometastases and circulating tumor cells to uracil and tegafur as evaluated using LacZ gene-tagged Lewis lung carcinoma cell

The chemosensitivity of the sequence of steps responsible for metastasis formation including circulating tumor cells and micrometastases to a 5-fluorouracil derivative (UFT) was examined with a novel micrometastasis model featuring Lewis lung carcinoma cells tagged with the bacterial LacZ gene and hygromycinR gene (hygR). Metastases in the lung could be specifically detected at the single-cell level by X-Gal staining after inoculation of LacZ-transfected tumor cells. Spontaneous metastasis in mice bearing subcutaneous primary tumors was significantly inhibited by UFT at doses of 15-20 mg/kg when it was orally administered from day 14, during the early stage of micrometastasis formation, but not by late administration from day 22. Experimental pulmonary metastasis was also inhibited without significant toxic side effects by oral administration of UFT at a daily dose of 20 mg/kg from day 4, when the tumor cells start new growth in the lung, but not by daily treatment from 8 days after intravenous injection. Oral administration of UFT had no effect on tumor cell arrest in the lung as detected by X-Gal staining. Furthermore, PCR analysis revealed that circulating tumor cells in the peripheral blood of mice bearing primary tumors after subcutaneous injection of hygR-tagged tumor cells were significantly reduced by the oral administration of UFT for 7 days in a dose-dependent manner. These results indicate that circulating tumor cells in the peripheral blood and micrometastases in the initial growth phase in the lungs are sensitive to this chemotherapeutic agent, and suggest that micrometastasis formation can be effectively inhibited by long-term oral administration of anticancer agents with minimal toxic side effects.

Effects of systemic and regional chemotherapy after hepatic resection for colorectal metastases

BACKGROUND

Although the survival benefit of hepatic resection for colorectal metastasis has been established, some controversy remains regarding the significance of adjuvant chemotherapy after hepatic resection.

METHODS

One hundred thirty-two consecutive patients who had liver resection for colorectal metastasis at our hospital between 1980 and 1997 were studied. After curative hepatic resection, 37 patients underwent systemic chemotherapy, administered orally or intravenously, and 38 patients underwent regional chemotherapy, given intra-arterially or intraportally. Forty patients had no adjuvant chemotherapy. The chemotherapeutic agents used for oral administration were uracil and Tegafur or Tegafur alone. Mitomycin C (MMC) or 5-FU was used for IV chemotherapy. Combinations of 5-FU/leucovorin or MMC/5-FU (doxorubicin) were used for regional chemotherapy. Univariate and multivariate analyses were applied to test the significance of adjuvant chemotherapy for patient survival or disease-free survival.

RESULTS

Overall 5-year survival was 42.2% (95% CL: 31.2%, 53.2%). Among the possible prognostic factors studied, univariate analysis showed a significant difference in survival based on the number of tumors and lymph node metastases in the hepatic hilum. There was a significant difference in disease-free survival based on adjuvant chemotherapy and lymph node metastasis. The multivariate analysis for patient survival selected four prognostic factors (P < .05), including adjuvant chemotherapy, lymph node metastasis, disease-free interval, and tumor size. The multivariate analysis for disease-free survival selected adjuvant chemotherapy, lymph node metastasis, and disease-free interval as significant factors. The most common recurrence site was remnant liver, regardless of adjuvant chemotherapy.

CONCLUSIONS

Adjuvant chemotherapy significantly improved survival and disease-free survival after hepatic resection for colorectal metastases. It did not decrease recurrence rate in the remnant liver.

Experimental chemotherapeutic agents for the treatment of colorectal carcinoma

Colorectal cancer is the third leading cause of cancer mortality for men and women in the United States. For the past 40 years fluorouracil has been the only agent with significant activity in this disease. More recently, advances in our understanding of the molecular biology of cancer have permitted the development of effective new agents for this disease. This article examines the current and future status of these new agents.

Cisplatin and UFT modulated with leucovorin for the treatment of Advanced non-small-cell lung cancer

We performed a phase II study to assess the efficacy and toxicity of the cisplatin-UFT-leucovorin (LV) combination in patients with advanced non-small-cell lung cancer (NSCLC). Twenty-five patients with measurable disease who had not received prior chemotherapy were entered into the trial. The therapeutic regimen consisted of cisplatin 90 mg/m(2) and i.v. LV 500 mg/m(2) on day 1, followed by oral UFT 390 mg/m(2)/day (in two doses on days 1 through 14. Patients also received oral LV 15 mg/12 h on days 2 through 14. Seventeen patients required reduced doses of UFT (200 mg/m(2) due to toxicity. Courses were repeated every 28 days for a minimum of three per patient. Three of 25 patients (12%) achieved a partial response (95% CI: 2.6 to 32.2%), two with 390 mg/m(2)/day and one with 200 mg/m(2)/day of UFT. The main side effects were hematological and gastrointestinal. In the courses including 390 mg/m(2)/day of UFT, grade 3-4 toxicity was leucopenia in 18% of the courses, nausea/vomiting in 27%, and diarrhea and epigastralgia in 13% each. Grade 3-4 toxicities for 200 mg/m(2)/day of UFT were leucopenia 2%, nausea/vomiting 9% and diarrhea 7%. In conclusion, this regimen cannot be recommend for the treatment of advanced NSCLC due to its low response rate and high toxicity.

Efficacy of oral tegafur modulation by uracil and leucovorin in advanced colorectal cancer. A phase II study

A phase II study was performed to assess the efficacy and toxicity of UFT (tegafur-uracil in the molar ratio 1:4) modulated with leucovorin (LV) in previously untreated patients with advanced colorectal carcinoma (CRC). 79 patients with measurable advanced colorectal cancer (CRC) and no prior chemotherapy were included. 75 patients were evaluable for toxicity and response. The regimen consisted of LV 500 mg/m2 administered intravenously on day 1, followed by oral UFT 390 mg/m2 on days 1-14. Patients received oral LV 15 mg every 12 h on days 2-14. Treatment was repeated every 28 days for a minimum of four courses per patient. Three hundred and ninety-eight cycles of chemotherapy were delivered (median five per patient). 7 patients (9%) had a complete response, and 22 a partial response for an overall response rate of 39%. Mild gastrointestinal toxicity was dose limiting: grade 3-4 diarrhoea appeared in 9% of patients. Other grade 3-4 toxicities were nausea/vomiting and mucositis in 4% of patients, gastric pain and leucopenia in 3%. Oral UFT modulated by oral LV is active in advanced CRC and can be administered on an outpatient basis with no significant toxicity requiring hospitalisation. Given its excellent tolerance profile and low toxicity, the regimen should be thoroughly studied and compared with 5-fluorouracil modulated by LV.

Randomized study with mitomycin C + 5-fluorouracil+cytosine arabinoside (MFC)+5-fluorouracil, MFC+tegafur and uracil (UFT), and MF+UFT in advanced gastric cancer: interinstitutional differences in a multicenter study in Japan

In a phase III randomized trial of adjuvant chemotherapy for gastric cancer, interinstitutional differences were analyzed. A trial of three regimens: mitomycin C, 5-fluorouracil(5-FU) and CA (MFC) + continuous oral 5-FU (Group C); MFC + continuous oral UFT(tegafur and uracil) (Group B); and MF + UFT (Group C) after operation was conducted in 466 patients with gastric cancer (stage II and III) at four hospitals in Japan (CIH, CAD, ACC and NCC). Patients were stratified by the institution, stage, and tumor size (8 cm ><). The 5-year survival rates were in the order of Group A (79.0%) > B (70.0%) > C (61.0%) (P = 0.1228) in total, A (95.0%) > B (80.0%) > C (58.0%) (P < 0.05) at CAD (82 patients), A > C > B at CIH (215), C > A > B at ACC (95), and B > A > C at NCC (78). The survival rate of patients with S2(serosal exposure), 8 cm < and N0-1 cancer was higher at CIH than at the other institutions. The interinstitutional differences in patient characteristics and surgical technique were more powerful than the differences among the three groups.

A phase II trial of oral tegafur and uracil plus cisplatin in patients with inoperable nonsmall cell lung cancer

BACKGROUND

The combination of uracil and tegafur in a 4:1 molar concentration (UFT) has a greater antitumor activity than 5-fluorouracil (5-FU) and tegafur. Because the combination of 5-FU and cisplatin has been proven to have a synergistic antitumor effect in many experimental and clinical studies, a Phase II study was conducted using the combination of UFT and cisplatin in patients with inoperable nonsmall cell lung cancer.

METHODS

Thirty-one patients with measurable disease were entered into the study; all were evaluable for toxicity and response. Their median age was 61 years (range, 36-75 years). There were 13 patients with Stage III and 17 with Stage IV disease. Twenty-two (71%) patients had received no prior treatment. UFT (400 mg/m2) was administered orally on days 1 through 21 and cisplatin (80 mg/m2) was injected intravenously on day 8. This treatment was repeated every 4 weeks.

RESULTS

The median number of treatment cycles was two (range, 1-4 cycles). There were 11 partial responses (35%; 95% confidence interval, 19%-52%). The median response time was 6 months (range, 3-13 months). The median survival time was 11 months (range, 4-27+ months) for Stage III and 8 months (range, 2-22 months) for Stage IV. This chemotherapy regimen was well tolerated. The hematologic toxicities, such as leukopenia and thrombocytopenia of grades 3 and 4, occurred in only 2 of 31 (6%) patients. Nonhematologic toxicities of grades 3 or 4 were not observed.

CONCLUSIONS

Oral UFT plus cisplatin administration demonstrated an activity comparable with that of other combinations based on cisplatin and an extremely low incidence of side effects. These observations suggest that this chemotherapy regimen is worthy of further investigation in a multi-institutional trial to determine the antitumor effect and the quality of life of patients.

1-(Tetrahydro-2-furanyl)-5-fluorouracil (Ftorafur) determined in rat hair as an index of drug exposure

The fluorescence derivatization of 1-(tetrahydro-2-furanyl)-5-fluorouracil (Ftorafur, FT) with 4-bromomethyl-6,7-dimethoxycoumarin (BrMdmc) with 18-crown-6 as catalyst was utilized for a sensitive and selective liquid chromatographic method to determine the concentration of FT in hair. Hair samples collected from rats, which had received FT intraperitoneally for 1 to 4 weeks, were dissolved in 1 M NaOH by heating at 80 degrees C for 30 min. A three-step extraction procedure for FT in the dissolved hair was used before and after the derivatization of FT with BrMdmc. The detection limit achieved was < 0.16 ng/mg hair. A dose-dependent accumulation of FT was evident in the rat hair (r = 0.914, p < 0.001): 0.24 +/- 0.07, 1.35 +/- 0.39, and 2.85 +/- 0.74 ng/mg hair (mean +/- SD, n = 4-5) at the doses of 5, 15, and 50 mg/kg/day for 4 weeks, respectively. In the rats that had received the highest dose of FT, the accumulation of FT in the hair depended also on the duration of FT administration: 0.82 +/- 0.33 (1 week), 1.52 +/- 0.38 (2 weeks), and 2.85 +/- 0.74 (4 weeks) ng/mg hair (n = 4-5). These findings suggest that the analysis of an oral antineoplasmic FT in the hair may be useful for assessing the degree of exposure to the drug.

Prophylactic oral UFT therapy for superficial bladder cancer

BACKGROUND

A randomized prospective trial was performed to determine whether long-term oral UFT (a 1:4 mixture of tegafur and uracil) (Taiho Pharmaceutical Co., Tokyo, Japan) therapy was effective in preventing the intravesical recurrence of superficial bladder cancer.

METHODS

A total of 112 patients with newly diagnosed superficial transitional cell carcinoma of bladder (Ta, T1 and G1 or G2) were randomized into a UFT-treated group (300-400 mg/d for 2 years) and a control group.

RESULTS

After a median follow-up period of 24.5 months, the recurrence rate was 25.7% for the UFT group and 43.3% for the control group (P = 0.015, log-rank test). Side effects of UFT administration were acceptably low.

CONCLUSIONS

These results suggest that long-term UFT administration after transurethral resection is effective in preventing the recurrence of superficial bladder cancer.