401 research outputs found

    Phase I study of intermittent and chronomodulated oral therapy with capecitabine in patients with advanced and/or metastatic cancer

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    BACKGROUND: The combination of capecitabine and gemcitabine at Fixed Dose Rate (FDR) has been demonstrated to be well tolerated, with apparent efficacy in patients with advanced cancers. FDR gemcitabine infusion leads to enhanced intracellular accumulation of drug and possible augmented clinical effect. The goals of this phase I study were to determine the maximum-tolerated dose (MTD) of chronomodulated capecitabine in patients with advanced cancer and to describe the dose-limiting toxicities (DLT), the safety profile of this way of administration. METHODS: Patients with advanced solid tumours who had failed to response to standard therapy or for whom no standard therapy was available were elegible for this study. Capecitabine was administered orally according to following schedule: 1/4 of dose at 8:00 a.m.; 1/4 of dose at 6:00 p.m. and 1/2 of dose at 11:00 p.m. each day for 14 consecutive days, followed by a 7-day rest period. RESULTS: All 27 patients enrolled onto the study were assessable for toxicity. The most common toxicities during the first two cycles of chemotherapy were fatigue, diarrhoea and hand foot syndrome (HFS). Only one out of the nine patients treated at capecitabine dose of 2,750 mg/m(2 )met protocol-specified DLT criteria (fatigue grade 4). However, at these doses the majority of cycles of therapy were delivered without dose reduction or delay. No other episodes of DLT were observed at the same dose steps and at the lower dose steps of capecitabine (1,500/1,750/2,000/2,250/2,500 mg/m(2)). The dose of 2,750 mg/m(2 )is recommended for further study. Tumor responses were observed in patients with metastatic breast and colorectal cancer. CONCLUSION: High doses of chronomodulated capecitabine can be administered with acceptable toxicity. The evidence of antitumor activity deserves further investigation in phase II combination chemotherapy studies

    Impact of Young Age on Treatment Efficacy and Safety in Advanced Colorectal Cancer: A Pooled Analysis of Patients From Nine First-Line Phase III Chemotherapy Trials

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    Colorectal cancer predominantly occurs in the elderly, but approximately 5% of patients are 50 years old or younger. We sought to determine whether young age is prognostic, or whether it influences efficacy/toxicity of chemotherapy, in patients with advanced disease

    Multi-Jet Event Rates in Deep Inelastic Scattering and Determination of the Strong Coupling Constant

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    Jet event rates in deep inelastic ep scattering at HERA are investigated applying the modified JADE jet algorithm. The analysis uses data taken with the H1 detector in 1994 and 1995. The data are corrected for detector and hadronization effects and then compared with perturbative QCD predictions using next-to-leading order calculations. The strong coupling constant alpha_S(M_Z^2) is determined evaluating the jet event rates. Values of alpha_S(Q^2) are extracted in four different bins of the negative squared momentum transfer~\qq in the range from 40 GeV2 to 4000 GeV2. A combined fit of the renormalization group equation to these several alpha_S(Q^2) values results in alpha_S(M_Z^2) = 0.117+-0.003(stat)+0.009-0.013(syst)+0.006(jet algorithm).Comment: 17 pages, 4 figures, 3 tables, this version to appear in Eur. Phys. J.; it replaces first posted hep-ex/9807019 which had incorrect figure 4

    Multiplicity Structure of the Hadronic Final State in Diffractive Deep-Inelastic Scattering at HERA

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    The multiplicity structure of the hadronic system X produced in deep-inelastic processes at HERA of the type ep -> eXY, where Y is a hadronic system with mass M_Y< 1.6 GeV and where the squared momentum transfer at the pY vertex, t, is limited to |t|<1 GeV^2, is studied as a function of the invariant mass M_X of the system X. Results are presented on multiplicity distributions and multiplicity moments, rapidity spectra and forward-backward correlations in the centre-of-mass system of X. The data are compared to results in e+e- annihilation, fixed-target lepton-nucleon collisions, hadro-produced diffractive final states and to non-diffractive hadron-hadron collisions. The comparison suggests a production mechanism of virtual photon dissociation which involves a mixture of partonic states and a significant gluon content. The data are well described by a model, based on a QCD-Regge analysis of the diffractive structure function, which assumes a large hard gluonic component of the colourless exchange at low Q^2. A model with soft colour interactions is also successful.Comment: 22 pages, 4 figures, submitted to Eur. Phys. J., error in first submission - omitted bibliograph

    Differential (2+1) Jet Event Rates and Determination of alpha_s in Deep Inelastic Scattering at HERA

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    Events with a (2+1) jet topology in deep-inelastic scattering at HERA are studied in the kinematic range 200 < Q^2< 10,000 GeV^2. The rate of (2+1) jet events has been determined with the modified JADE jet algorithm as a function of the jet resolution parameter and is compared with the predictions of Monte Carlo models. In addition, the event rate is corrected for both hadronization and detector effects and is compared with next-to-leading order QCD calculations. A value of the strong coupling constant of alpha_s(M_Z^2)= 0.118+- 0.002 (stat.)^(+0.007)_(-0.008) (syst.)^(+0.007)_(-0.006) (theory) is extracted. The systematic error includes uncertainties in the calorimeter energy calibration, in the description of the data by current Monte Carlo models, and in the knowledge of the parton densities. The theoretical error is dominated by the renormalization scale ambiguity.Comment: 25 pages, 6 figures, 3 tables, submitted to Eur. Phys.

    Measurements of Transverse Energy Flow in Deep-Inelastic Scattering at HERA

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    Measurements of transverse energy flow are presented for neutral current deep-inelastic scattering events produced in positron-proton collisions at HERA. The kinematic range covers squared momentum transfers Q^2 from 3.2 to 2,200 GeV^2, the Bjorken scaling variable x from 8.10^{-5} to 0.11 and the hadronic mass W from 66 to 233 GeV. The transverse energy flow is measured in the hadronic centre of mass frame and is studied as a function of Q^2, x, W and pseudorapidity. A comparison is made with QCD based models. The behaviour of the mean transverse energy in the central pseudorapidity region and an interval corresponding to the photon fragmentation region are analysed as a function of Q^2 and W.Comment: 26 pages, 8 figures, submitted to Eur. Phys.

    Energy Flow in the Hadronic Final State of Diffractive and Non-Diffractive Deep-Inelastic Scattering at HERA

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    An investigation of the hadronic final state in diffractive and non--diffractive deep--inelastic electron--proton scattering at HERA is presented, where diffractive data are selected experimentally by demanding a large gap in pseudo --rapidity around the proton remnant direction. The transverse energy flow in the hadronic final state is evaluated using a set of estimators which quantify topological properties. Using available Monte Carlo QCD calculations, it is demonstrated that the final state in diffractive DIS exhibits the features expected if the interaction is interpreted as the scattering of an electron off a current quark with associated effects of perturbative QCD. A model in which deep--inelastic diffraction is taken to be the exchange of a pomeron with partonic structure is found to reproduce the measurements well. Models for deep--inelastic epep scattering, in which a sizeable diffractive contribution is present because of non--perturbative effects in the production of the hadronic final state, reproduce the general tendencies of the data but in all give a worse description.Comment: 22 pages, latex, 6 Figures appended as uuencoded fil

    Measurement of Leading Proton and Neutron Production in Deep Inelastic Scattering at HERA

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    Deep--inelastic scattering events with a leading baryon have been detected by the H1 experiment at HERA using a forward proton spectrometer and a forward neutron calorimeter. Semi--inclusive cross sections have been measured in the kinematic region 2 <= Q^2 <= 50 GeV^2, 6.10^-5 <= x <= 6.10^-3 and baryon p_T <= MeV, for events with a final state proton with energy 580 <= E' <= 740 GeV, or a neutron with energy E' >= 160 GeV. The measurements are used to test production models and factorization hypotheses. A Regge model of leading baryon production which consists of pion, pomeron and secondary reggeon exchanges gives an acceptable description of both semi-inclusive cross sections in the region 0.7 <= E'/E_p <= 0.9, where E_p is the proton beam energy. The leading neutron data are used to estimate for the first time the structure function of the pion at small Bjorken--x.Comment: 30 pages, 9 figures, 2 tables, submitted to Eur. Phys.

    A novel biweekly multidrug regimen of gemcitabine, oxaliplatin, 5-fluorouracil (5-FU), and folinic acid (FA) in pretreated patients with advanced colorectal carcinoma

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    Previous results suggest that GEM affects 5-fluorouracil (5-FU) metabolism and pharmacokinetics in cancer patients, while combined with oxaliplatin, levo-folinic acid, and 5-FU (GOLF regimen), at doses achievable in cancer patients, determines high cytotoxic and proapoptotic antitumour activity in colon cancer cells in vitro. On these bases we designed a phase I–II clinical trial testing the GOLF regimen in patients with metastatic colorectal carcinoma, who had received at least a prior line of chemotherapy. In total, 29 patients (20 males and nine females) enrolled in the study received every 2 weeks, gemcitabine (patients #1–3 received 600 mgm2; patients # 4–6 received 850 mgm2; while patients # 7–29 received 1000 mgm2) on the day 1, levo-folinic acid (100 mgm2) on the days 1 and 2; 5-fluorouracil (400 mgm2) in bolus injection, followed by a 22-h continuous infusion (800 mgm2) on the days 1 and 2, and oxaliplatin (85 mgm2), 6 h after the 5-FU bolus on day 2. The most frequent side effect was grade I–II haematological toxicity. In total, 28 patients were evaluable for response: three achieved a complete response, nine a partial response, 10 had a stable disease, and six progressed. The average time to progression and overall survival of the patients was, respectively, 7.26 and 22 months. Our GOLF combination is well tolerated and seems promising for the treatment of advanced colorectal cancer
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