, proposed and designed the study

B. H. , J. H. , J. D. , A. N. , F. L. et al.,

B. H. , J. H. , Z. A. , J. H. , and L. A. , planned the evaluations

B. H. and J. ,

B. H. and L. A. ,

V. M. and V. T. , studied biopsy specimens

F. C. and J. E. , reviewed all the biopsy specimens

J. E. and V. ,

B. H. , J. H. , L. A. , F. C. , J. E. et al., wrote the manuscript; and all authors approved the final manuscript. A list of members of the French Histiocytoses Study Group appears in "Appendix

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