*Department of Pathology, Robert J. Tomsich Pathology and Laboratory Medicine Institute, Cleveland Clinic, Cleveland, OH

†Sarcoma Unit, The Royal Marsden Hospital, London

§Department of Musculoskeletal Pathology, University Hospitals Birmingham, Birmingham UK

‡Department of Pathology, University of Pittsburgh, Pittsburgh, PA

Departments of ∥Quantitative Health Sciences

¶Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN

Conflicts of Interest and Source of Funding: The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article.

Correspondence: Karen J. Fritchie, MD, Department of Anatomic Pathology, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (e-mail: [email protected]).