Since the publication of the Revised European-American Classification of Lymphoid Neoplasms in 1994, subsequent updates of the classification of lymphoid neoplasms have been generated through iterative international efforts to achieve broad consensus among hematopathologists, geneticists, molecular scientists, and clinicians. Significant progress has recently been made in the characterization of malignancies of the immune system, with many new insights provided by genomic studies. They have led to this proposal. We have followed the same process that was successfully used for the third and fourth editions of the World Health Organization Classification of Hematologic Neoplasms. The definition, recommended studies, and criteria for the diagnosis of many entities have been extensively refined. Some categories considered provisional have now been upgraded to definite entities. Terminology for some diseases has been revised to adapt nomenclature to the current knowledge of their biology, but these modifications have been restricted to well-justified situations. Major findings from recent genomic studies have impacted the conceptual framework and diagnostic criteria for many disease entities. These changes will have an impact on optimal clinical management. The conclusions of this work are summarized in this report as the proposed International Consensus Classification of mature lymphoid, histiocytic, and dendritic cell tumors.
Bibliographical noteFunding Information:
E.S.J., L.M.S., and J.I.C. were supported by the intramural research programs of the Center for Cancer Research, National Cancer Institute (E.S.J., ZIA SC 000550; L.M.S., ZIABC011780) and the National Institute of Allergy and Infectious Diseases (J.I.C., ZIAAI000058). Funding for the work of the CAC was received from many sources as previously cited. 5
We dedicate this report to the memory of Paul Kleihues (21 May 1936–17 March 2022), former director of the International Agency for Research on Cancer (IARC) (1994-2003), a visionary leader who created the modern WHO Blue Book series for the classification of tumors. E.S.J. L.M.S. and J.I.C. were supported by the intramural research programs of the Center for Cancer Research, National Cancer Institute (E.S.J. ZIA SC 000550; L.M.S. ZIABC011780) and the National Institute of Allergy and Infectious Diseases (J.I.C. ZIAAI000058). Funding for the work of the CAC was received from many sources as previously cited.5
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