1,721,021 research outputs found
Initial dose intensity has limited impact on the outcome of ABVD chemotherapy for advanced Hodgkin's Lymphoma (HL): Data from UKLG LY09 (ISRCTN97144519)
No full textBackground. Response-adjusted therapy is attractive in the treatment
of HL, to avoid over-treatment of patients with a good prognosis and to
maximise the chance of cure. However, it is not clear whether the intensity
of initial therapy prior to early response assessment is critical to the
outcome, or whether subsequent intensification may compensate for
less intense initial treatment. We investigated whether dose intensity in
the first two cycles of standard ABVD chemotherapy is predictive of progression-
free survival (PFS).Methods. Data for 379 eligible patients allocated to receive ABVD in
the UKLG LY09 trial and who received at least two cycles of chemotherapy
were included. All patients were planned to have 6 cycles of
chemotherapy, extended to 8 where there was evidence of continuing
response at 6. Growth factor support was permitted following delays or
reductions in treatment. Radiotherapy was recommended for residual
masses or at the sites of prior bulk disease. Patients were recruited
between 1998 and 2002 with median follow-up of 52 months. Observed
dose was standardised by dividing by expected dose for the first two
cycles. Dose intensity was defined as standardised dose divided by
[observed duration for two cycles divided by expected duration for two
cycles]. These were calculated separately for doxorubicin, bleomycin,
dacarbazine and vinblastine and averaged. Landmark analyses were
timed from the start of cycle 3. The analyses include 96 PFS events: disease
progression or death from HL.Results. 93/397 (25%) of patients received treatment at >97% intended
DI (averaged across all 4 drugs) for cycles 1-2, whilst 137 (37%)
received 86-97% and 147 (39%) less than 86%. Dose and dose intensity
in cycles 1-2 correlated well with dose and dose intensity in the
remaining cycles 3-6 for all drugs. There was no good evidence from
unadjusted univariate analyses of the four drugs individually and their
average, that higher dose intensity in the first two cycles was associated
with better PFS. Adjusting for baseline IPI score, the strongest effect of a 10% increase in DI in cycles 1-2 was from Doxorubicin. This was associated
with a hazard ratio of 0.90 (95%CI 0.78, 1.02); bleomycin HR=0.90
(95%CI 0.78, 1.05), dacarbazine HR=0.92 (95%CI 0.79, 1.06), vinblastine
HR=0.94 (95%CI 0.81, 1.09). Among 82 patients who had cycles 3-6
delivered at over 97% DI on average, patients who received average DI
below 86% in cycles 1-2 had the same long-term PFS as those patients
who received average DI over 97% in cycles 1-2. Poorer DI in cycles 1-2
was associated with increased use of G-CSF during subsequent cycles.Discussion. We have found no evidence of improved PFS with higher
dose intensity in the first two cycles of ABVD. This is a non-randomised
comparison and caution is needed in the interpretation of such retrospective
data. However, the data comes from a large cohort of patients following
a standard treatment regimen, ABVD, in the context of a randomised
controlled trial. It is possible that following initial low dose
intensity, growth factors were effectively used to restore the efficacy of
treatment and/or chemotherapy was continued for more cycles and/or
consolidation radiotherapy used. This does not appear to support the
introduction of a policy of maximising initial dose intensity without
testing in a further prospective study
Consolidation radiotherapy in patients with advanced Hodgkin lymphoma: survival data from the UKLG LY09 randomised controlled trial (ISRCTN97144519)
No full textPurpose: this study analyzed the outcomes of nonrandomized consolidation radiotherapy (RT) given after chemotherapy in the initial treatment of advanced Hodgkin's lymphoma (HL). The results were collected prospectively within a randomized controlled trial of induction chemotherapy.Patients and methods: patients were randomly assigned between doxorubicin, bleomycin, vinblastine, and dacarbazine and one of two prespecified multidrug regimens. At least six cycles of chemotherapy were planned, with up to eight for patients showing slower response. Involved-field RT was recommended for incomplete response to chemotherapy or bulk disease at presentation. The primary outcome measure was progression-free survival (PFS), landmarked from the end of chemotherapy.Results: among 807 patients randomly assigned, 702 achieved objective response. Postchemotherapy RT for consolidation was reported in 300 (43%). With median follow-up of 6.9 years, 161 PFS events and 83 deaths were reported. Baseline characteristics showed more patients with bulk disease having RT (190 [63%] v 111 [28%]) and only partial response after chemotherapy (150 [50%] v 36 [9%]). Other baseline characteristics were similar. PFS was superior for patients having RT (hazard ratio [HR], 0.43; 95% CI, 0.30 to 0.60) with 5-year PFS 71% without RT, 86% with RT. A similar advantage was seen for overall survival (HR, 0.47; 95% CI, 0.29 to 0.77). There was no evidence of heterogeneity of treatment effect across subgroups.Conclusion: patients who received consolidation RT apparently had better outcomes, consistently across all prognostic groups which persisted in multivariate analysis. This suggests that RT contributes significantly to the cure rate for advanced HL, although patient selection for combined modality treatment requires better definition in prospective trials
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
An international evaluation of CODOX-M and CODOX-M alternating with IVAC in adult Burkitt's lymphoma: results of United Kingdom Lymphoma Group LY06 study
No full textBackground: Burkitt’s lymphoma (BL) is a rare and rapidly progressive form of B-cell non-Hodgkin’s lymphoma. Cyclophosphamide, vincristine, doxorubicin, high-dose methotrexate (CODOX-M)/ifosfamide, etoposide and high-dose cytarabine (IVAC) is a highly effective alternating non-cross-resistant regimen developed by Magrath et al. (Magrath I., Adde M., Shad A. et al. J Clin Oncol 1996; 14: 925–934) at the US National Cancer Institute. The aim was to confirm these results in a larger, international, multi-centre study using International Prognostic Index-based criteria to assign prognostic groups, whilst slightly simplifying the protocol.Patients and methods: a phase II study where: (i) low risk (LR) patients were treated with three cycles of modified CODOX-M; and (ii) high risk (HR) patients received treatment with four cycles of alternating modified CODOX-M and IVAC chemotherapy. Target of 60 patients, fit for protocol treatment, from 16 to 60 years of age with locally diagnosed, non-HIV-related, non-organ-transplant-related BL.Results: results are given for 52 of 72 registered patients whose pathological eligibility was confirmed by central pathology review: 12 LR plus 40 HR. The majority of patients (n = 41) completed protocol treatment, but toxicity was severe, especially myelosuppression and mucositis. Overall, 2-year event-free survival (EFS) was 64.6% (95% CI 50.4% to 78.9%) and 2-year overall survival (OS) was 72.8% (95% CI 59.4% to 86.3%). For LR, 2-year EFS was 83.3% and OS was 81.5%. For HR, 2-year EFS was 59.5% and OS was 69.9%.Conclusions: this study confirms high cure rates with this CODOX-M/IVAC approach
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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