Adélaïde Doussau

Organ preservation for rectal cancer (GRECCAR 2): a prospective, randomised, open-label, multicentre, phase 3 trial

BACKGROUND Organ preservation is a concept proposed for patients with rectal cancer after a good clinical response to neoadjuvant chemotherapy, to potentially avoid morbidity and side-effects of rectal excision. The objective of this study was to compare local excision and total mesorectal excision in patients with a good response after chemoradiotherapy for lower rectal cancer. METHODS We did a prospective, randomised, open-label, multicentre, phase 3 trial at 15 tertiary centres in France that were experts in the treatment of rectal cancer. Patients aged 18 years and older with stage T2T3 lower rectal carcinoma, of maximum size 4 cm, who had a good clinical response to neoadjuvant chemoradiotherapy (residual tumour ≤2 cm) were centrally randomly assigned by the surgeon before surgery to either local excision or total mesorectal excision surgery. Randomisation, which was done via the internet, was not stratified and used permuted blocks of size eight. In the local excision group, a completion total mesorectal excision was required if tumour stage was ypT2-3. The primary endpoint was a composite outcome of death, recurrence, morbidity, and side-effects at 2 years after surgery, to show superiority of local excision over total mesorectal excision in the modified intention-to-treat (ITT) population (expected proportions of patients having at least one event were 25% vs 60% for superiority). This trial was registered with ClinicalTrials.gov, number NCT00427375. FINDINGS From March 1, 2007, to Sept 24, 2012, 186 patients received chemoradiotherapy and were enrolled in the study. 148 good clinical responders were randomly assigned to treatment, three were excluded (because they had metastatic disease, tumour >8 cm from anal verge, and withdrew consent), and 145 were analysed: 74 in the local excision group and 71 in the total mesorectal excision group. In the local excision group, 26 patients had a completion total mesorectal excision. At 2 years in the modified ITT population, one or more events from the composite primary outcome occurred in 41 (56%) of 73 patients in the local excision group and 33 (48%) of 69 in the total mesorectal excision group (odds ratio 1·33, 95% CI 0·62-2·86; p=0·43). In the modified ITT analysis, there was no difference between the groups in all components of the composite outcome, and superiority was not shown for local excision over total mesorectal excision. INTERPRETATION We failed to show superiority of local excision over total mesorectal excision, because many patients in the local excision group received a completion total mesorectal excision that probably increased morbidity and side-effects, and compromised the potential advantages of local excision. Better patient selection to avoid unnecessary completion total mesorectal excision could improve the strategy. FUNDING National Cancer Institute of France, Sanofi, Roche Pharma.

Dose-finding design using mixed-effect proportional odds model for longitudinal graded toxicity data in phase I oncology clinical trials.

Phase I oncology clinical trials are designed to identify the optimal dose that will be recommended for phase II trials. This dose is typically defined as the dose associated with a certain probability of severe toxicity during the first cycle of treatment, although toxicity is repeatedly measured over cycles on an ordinal scale. We propose a new adaptive dose-finding design using longitudinal measurements of ordinal toxic adverse events, with proportional odds mixed-effect models. Likelihood-based inference is implemented. The optimal dose is then the dose producing a target rate of severe toxicity per cycle. This model can also be used to identify cumulative or late toxicities. The performances of this approach were compared with those of the continual reassessment method in a simulation study. Operating characteristics were evaluated in terms of correct identification of the target dose, distribution of the doses allocated and power to detect trends in the risk of toxicities over time. This approach was also used to reanalyse data from a phase I oncology trial. Use of a proportional odds mixed-effect model appears to be feasible in phase I dose-finding trials, increases the ability of selecting the correct dose and provides a tool to detect cumulative effects.

Diagnostic and Prognostic Value of BCL2 Rearrangement in 53 Patients With Follicular Lymphoma Presenting as Primary Skin Lesions

OBJECTIVES To study the diagnostic value of BCL2 rearrangement in follicle center lymphoma (FCL) presenting as primary skin lesions, evaluate its prevalence and the prognostic value in primary cutaneous FCL (PCFCL), and assess prognostic factors in PCFCL. METHODS Fifty-three patients with a cutaneous presentation of FCL without a history of nodal lymphoma were selected retrospectively. Clinical and histologic data were collected together with staging and follow-up data. A fluorescence in situ hybridization (FISH) test for BCL2 split probes was performed on skin biopsy specimens. RESULTS Initial staging procedures identified 47 PCFCLs and six cases of secondary skin involvement of FCL (SSIFCL). FISH detected seven cases carrying a BCL2 rearrangement: four (8.5%) of 47 PCFCLs and three (50%) of six SSIFCLs. These seven cases coexpressed BCL2 and CD10. In PCFCL, cutaneous relapse rate was 42.6%. A small/medium centrocytic cell population was associated with a higher probability of skin relapse in univariate (P = .008) and multivariate (P = .028) analysis, and BCL2 rearrangement detection was associated with secondary extracutaneous spreading (P = .05). CONCLUSIONS We observed that BCL2 rearrangement in PCFCL is rare, associated with initial positivity of staging (diagnostic value) or with secondary extracutaneous spreading (prognostic value). In selected cases with BCL2-CD10 coexpression, FISH testing could detect patients with poor outcome and require closer monitoring.

Fresh‐frozen plasma transfusion did not reduce 30‐day mortality in patients undergoing cardiopulmonary bypass cardiac surgery with excessive bleeding: the PLASMACARD multicenter cohort study

During on‐pump cardiac surgery, hemorrhagic complications occur frequently. Fresh‐frozen plasma (FFP) is widely transfused to provide coagulation factors. Yet, no randomized clinical trial has demonstrated its benefits on mortality. We assessed the relationship between therapeutic transfusion of FFP and 30‐day mortality in cardiac surgery patients suffering from excessive bleeding in a prospective cohort study.

Dose finding with longitudinal data: simpler models, richer outcomes

Phase I oncology clinical trials are designed to identify the optimal dose that will be recommended for phase II trials. This dose is typically defined as the dose associated with a certain probability of severe toxicity at cycle 1, although toxicity is repeatedly measured over cycles on an ordinal scale. Recently, a proportional odds mixed-effect model for ordinal outcomes has been proposed to (i) identify the optimal dose accounting for repeated events and (ii) to provide some framework to explore time trend. We compare this approach to a method based on repeated binary variables and to a method based on an under-parameterized model of the dose-time toxicity relationship. We show that repeated binary and ordinal outcomes both improve the accuracy of dose-finding trials in the same proportion; ordinal outcomes are, however, superior to detect time trend even in the presence of nonproportional odds models. Moreover, less parameterized models led to the best operating characteristics. These approaches are illustrated on two dose-finding phase I trials. Integration of repeated measurements is appealing in phase I dose-finding trials.

Accelerating clinical development of HIV vaccine strategies: methodological challenges and considerations in constructing an optimised multi-arm phase I/II trial design.

BackgroundMany candidate vaccine strategies against human immunodeficiency virus (HIV) infection are under study, but their clinical development is lengthy and iterative. To accelerate HIV vaccine development optimised trial designs are needed. We propose a randomised multi-arm phase I/II design for early stage development of several vaccine strategies, aiming at rapidly discarding those that are unsafe or non-immunogenic.MethodsWe explored early stage designs to evaluate both the safety and the immunogenicity of four heterologous prime-boost HIV vaccine strategies in parallel. One of the vaccines used as a prime and boost in the different strategies (vaccine 1) has yet to be tested in humans, thus requiring a phase I safety evaluation. However, its toxicity risk is considered minimal based on data from similar vaccines. We newly adapted a randomised phase II trial by integrating an early safety decision rule, emulating that of a phase I study. We evaluated the operating characteristics of the proposed design in simulation studies with either a fixed-sample frequentist or a continuous Bayesian safety decision rule and projected timelines for the trial.ResultsWe propose a randomised four-arm phase I/II design with two independent binary endpoints for safety and immunogenicity. Immunogenicity evaluation at trial end is based on a single-stage Fleming design per arm, comparing the observed proportion of responders in an immunogenicity screening assay to an unacceptably low proportion, without direct comparisons between arms. Randomisation limits heterogeneity in volunteer characteristics between arms. To avoid exposure of additional participants to an unsafe vaccine during the vaccine boost phase, an early safety decision rule is imposed on the arm starting with vaccine 1 injections. In simulations of the design with either decision rule, the risks of erroneous conclusions were controlled <15%. Flexibility in trial conduct is greater with the continuous Bayesian rule. A 12-month gain in timelines is expected by this optimised design. Other existing designs such as bivariate or seamless phase I/II designs did not offer a clear-cut alternative.ConclusionsBy combining phase I and phase II evaluations in a multi-arm trial, the proposed optimised design allows for accelerating early stage clinical development of HIV vaccine strategies.

Dose Finding Methods in Oncology: From the Maximum Tolerated Dose to the Recommended Phase II Dose

Phase I oncology clinical trials are designed to identify the optimal dose that will be recommended for phase II trials. This dose is typically defined as the dose associated with a certain probability of dose limiting toxicity (DLT) during the first cycle of treatment, although toxicity is repeatedly measured over cycles on an ordinal scale. We present the main dose finding methods developed in the era of cytotoxic agents. We illustrate their properties and limitations in different scenarios. We also explore different implementations of these methods that have been proposed in a Bayesian or likelihood framework or that can rely on several dose-toxicity models. We highlight the fact that the binary nature of the primary outcome (DLT or no DLT) drastically limits the performances of any methods. We then present adaptive dose-finding designs that use toxicity measurements at all cycles of treatment and not only the first one; some authors have proposed to consider the DLT as a time to event variable while others have analyzed the longitudinal measurements of toxic side events. This however raises the delicate issue of the definition of the optimal dose. These approaches are illustrated on two dose finding phase I trials; data are reanalysed and results are compared and discussed. Integration of richer information appears appealing in phase I dose-finding trials, as it gives more accurate estimates of the risk of toxicity and increases the ability of selecting the correct dose. Use of longitudinal data in addition allows for detecting cumulative or delayed effects of strong magnitude. Model-based methods give a flexible framework for using more complete data.