Hematopoietic Neoplasms: Controversies in Diagnosis and Classification
P re f a c e Why Is Hematopathology so Complicated?
Daniel A. Arber, MD
Tracy I. George, MD
Editors
the diagnosis of classic diseases such as Hodgkin lymphoma, discussed in article 7. In article 9, the differential diagnosis of eosinophilia in hematopathology is described, including diagnostic algorithms useful in identifying these rare neoplasms and the clinical implications of specific genetic abnormalities with respect to treatment. In the final article, the challenges of integrating ancillary testing into a comprehensive report is discussed and the importance of developing such a report is highlighted. We hope this issue will serve as a practical guide for pathologists that can be used in daily practice. While we cannot make the classification of these tumors less complicated, we hope this series of articles will help the readers understand the selected disorders better. As with most tasks, it is the people that make such a series possible and we commend the authors on eloquently sharing their expertise with outstanding images, salient tables, and clear summaries. Daniel A. Arber, MD Department of Pathology Stanford University Stanford, CA 94305, USA Tracy I. George, MD Hematopathology Section University of New Mexico School of Medicine Albuquerque, NM 87131, USA E-mail addresses:
[email protected] (D.A. Arber)
[email protected] (T.I. George)
Surgical Pathology 6 (2013) ix http://dx.doi.org/10.1016/j.path.2013.08.004 1875-9181/13/$ – see front matter Ó 2013 Elsevier Inc. All rights reserved.
surgpath.theclinics.com
Hematopathology is well known for its complicated classification systems that seem to change every few years. Unfortunately, this trend will only continue and has spread to other areas of diagnostic pathology as we learn more about the complex diseases that we diagnose. Changes in classification systems, however, are usually driven by advances in the field. This volume of Surgical Pathology Clinics highlights selected topics in hematopathology that have seen critical advances in recent years and pose diagnostic challenges for the practicing pathologist. The first article focuses on the clonal link between malignant lymphoma and histiocytic tumors; a discovery that has further confirmed the plasticity of hematopoietic progenitor cells. In the second article, the clues to assist in the separation of reactive from leukemic large granular lymphocyte proliferations are discussed. This is followed by articles on erythroleukemia, myeloid neoplasms with inv(3)/t(3;3), and updates on myelodysplastic syndrome. These three articles highlight the difficulty of separating myelodysplastic syndromes from acute leukemia, the importance of specific genetic abnormalities in establishing these diagnoses and the role of genetic abnormalities in prognosis. Two “new” categories of acute leukemia, early precursor T-cell acute leukemia and blastic plasmacytoid dendritic cell tumors, are described and how to distinguish these acute leukemias from morphologic and immunophenotypic mimics, and the therapeutic implications of these diagnoses are reviewed. As new immunohistochemical markers and technology are used in pathology, this brings difficulties in
