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2008 112: 3527-doi:10.1182/blood-2008-05-160010 About reporting clinical trials
Jean-Louis Bernard, Julie Berbis, Laurent Boyer and Vincent Pradel
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major thrombosis and platelet number in this untreated group. Results Correspondence: Tiziano Barbui, Divisione di Ematologia, Ospedali Riuniti, have shown a hazard ratio (HR) of 0.65 (95% confidence interval [CI] Largo Barozzi 1, 24100 Bergamo, Italy; e-mail: tbarbui@ospedaliriuniti.
bergamo.it. 0.31-1.25; P ϭ .15) for patients with a platelet count more than1000 ϫ 109/L. Thus, a clear, albeit not significant, trend toward “moreplatelets, less thrombosis” can be observed also in these patients.
Overall, we are happy to share with Dr Tefferi the belief that thrombocy- References
tosis, per se, should not be taken as a good reason to give cytotoxic Barbui T, Barosi G, Grossi A, et al. Practice guidelines for the therapy of essen- chemotherapy to otherwise low-risk ET patients.
tial thrombocythemia. A statement from the Italian Society of Hematology, theItalian Society of Experimental Hematology and the Italian Group for Bone Mar- Tiziano Barbui, Alessandra Carobbio, and Guido Finazzi
row Transplantation. Haematologica. 2004;89:215-232.
Tefferi A, Gangat N, Wolanskyj AP. Management of extreme thrombocytosis in Conflict-of-interest disclosure: The authors declare no competing financial otherwise low-risk essential thrombocythemia; does number matter? [letter] About reporting clinical trials
As members of a French research ethics committee, a recent paper treatment intensification for the population included in this on the treatment of multisystem Langerhans cell histiocytosis study despite encouraging results for patients with risk or- (MS-LCH) by Gadner et al1 was brought to our attention. The gan involvement. Despite the low number of controlled studies authors’ efforts to conduct an international randomized controlled in this disease, a systematic review4 of all the available trials trial on this orphan disease are worthy but this report leads us to could be useful to consolidate the conclusion.5 We advocate reporting conclusions of clinical trials for themselves with The title and the conclusion of the abstract (“intensified accurate title and abstract in order to prevent any confusion treatment significantly increases rapid response and reduces among physicians and offer patients the best return benefits mortality in risk MS-LCH”) do not reflect the main findings of the LCH-II study, albeit adequately presented in the results anddiscussion sections of the article. This study showed no Jean-Louis Bernard, Julie Berbis, Laurent Boyer, and Vincent Pradel
significant difference for risk patients (ie, with risk organ This work was supported by the Research ethics committee Sud-Me´diterrane´e involvement or age of onset younger than 2 years) between conventional and intensified treatment for the primary (rapidresponse) and the secondary endpoints (survival probability, Contribution: V.P., J.B., and L.B. performed the critical analysis of methodology, disease reactivation frequency, and sequelae). The quality of the and J.-L.B., V.P., and J.B. wrote the paper. trial is not in question; it was adequately designed and Conflict-of-interest disclosure: The authors declare no competing financial conducted to detect a 20% difference in rapid response between the 2 arms, but was underpowered to detect a difference as small Correspondence: Pr Jean-Louis Bernard, CPP Sud-Me´diterrane´e II, 249 Bd de Sainte Marguerite, 13274 Marseille cx 09, France; e-mail: jean-louis. The abstract’s conclusion is based on 2 exploratory analyses.
(1) The reduction of mortality in LCH-II arm B versus arm A issuedfrom a subgroup analysis (patients with risk organ involvement) ona secondary end point with an adjustment on the risk organs References
involved. The justification of this adjustment is not given in the Gadner H, Grois N, Po¨tschger U, et al. Improved outcome in multisystem Lang- article and the high P value (.049) does not exclude a chance erhans cell histiocytosis is associated with therapy intensification. Blood. 2008; result.2 (2) The pooled analysis of LCH-I3 and LCH-II1 studies is not justified in the article; we do not know whether this pooled Brookes ST, Whitley E, Peters TJ, et al. Subgroup analyses in randomised con-trolled trials: quantifying the risks of false-positives and false-negatives. Health analysis was planned a priori or not. Moreover, the tests used in this pooled analysis implicitly assume that there is a continuous Gadner H, Grois N, Arico M, et al. A randomized trial of treatment for multisys- intensification of treatment from arm A LCH-I to arm B LCH-II.
tem Langerhans’ cell histiocytosis. J Pediatr. 2001;138:728-734.
This assumption is not established: LCH-I compared 2 drugs Crumley ET, Wiebe N, Cramer K, et al. Which resources should be used toidentify RCT/CCTs for systematic reviews: a systematic review. BMC Med Res (vinblastine vs etoposide) without any notion of intensification, and Methodol. 2005;5:24; DOI: 10.1186/1471-2288-5-24.
the affirmation that arm A LCH-II was more intensive than arm B Shrier I, Boivin JF, Platt RW, et al. The interpretation of systematic reviews with LCH-I is debatable, at least in relation with the main criterion meta-analyses: an objective or subjective process? BMC Med Inform Decis Mak. 2008;8:19; DOI: 10.1186/1472-6947-8-19.
Bernard JL, Aubert-Fourmy C. La publicite´ des travaux et la publication des The main message of the LCH-II trial is correctly pre- re´sultats des recherches en pe´diatrie, une question d’e´thique. Arch Pediatr.
sented in the discussion: there was no significant effect of

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