Who-HEM5 and ICC(2022) Classifications for Myeloid Neoplasms

The latest 5th edition of the World Health Organization classification of hematolymphoid neoplasms (WHO-HEM5) (2022) and the International Consensus Classification (ICC) (2022) of myeloid neoplasms provide the basic framework and guidance for sub-classification of various myeloid proliferations and neoplasms. The updated biological information defined by the underlying genetic abnormalities has been given due consideration in the current classifications of myeloid neoplasms. Although the broad underlying principles of the WHO-HEM5 and ICC classifications of myeloid neoplasms are similar, however, there are minor differences. So, in addition to enumerating the WHO-HEM5 and ICC sub-classes of myeloid neoplasms, the key differences of these classifications have been highlighted in this chapter. The differences leading to the diagnostic challenges have also been highlighted with the help of a few clinical scenarios, particularly for acute myeloid leukemia (AML) and myelodysplastic neoplasms (MDS).