Book excerpt: Management of tumor patients now relies on new individualized approaches to treatment, requiring extensive knowledge of the molecular makeup of tumors. Updated and expanded, the third edition of Atlas of Differential Diagnosis in Neoplastic Hematopathology examines not only the differential diagnosis but also the detailed morphologic, immunophenotypic, and especially genetic characteristics of the majority of hematolymphoid malignancies. Featuring a new structure and including new chapters, the third edition updates all content and presents considerable expansion on many topics, including: Metaphase cytogenetic and FISH Flow cytometry (overview and detailed analysis of specific tumors) Acute myeloid leukemia and new classification schemes MDS, AML, and B- and T-cell lymphoproliferations Abnormal patterns in the lymph node and bone marrow with detail differential diagnosis based on histologic features and cellular composition Detailed differential diagnosis based on the expression of broad list of antigenic markers (flow cytometry and immunohistochemistry) Extranodal lymphomas Diagnosis of MDS and myeloproliferative neoplasm and their differential diagnosis based on the morphologic, flow cytometric, and chromosomal features The book also provides expanded differential diagnosis of the most common as well as most difficult and rare entities, including morphologic, immunophenotypic, and karyotypic/molecular features. This edition includes updated algorithms for most common diagnoses as well as several new algorithms. The majority of figures have been revised and are in full color.