Robert P. Hasserjian¹

¹Department of Pathology, Massachusetts General Hospital, Boston, MA, USA

 

While the initial diagnostic criteria for myeloid neoplasms are codified in formal classification schemes such as the International Consensus Classification and 5^th edition World Health Organization Classification, these schemes provide little guidance on how to diagnose myeloid neoplasms that have progressed or been altered by therapy. Aside from increases and decreases in blast percentages, which are incorporated into published treatment response guidelines for acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS), these diseases may show alterations in blast morphology, hematopoietic maturation, and dysplasia.  Genetic aberrations found at the time of initial diagnosis may disappear, increase or decrease in variant allele fraction (VAF), or new abnormalities may appear. Moreover, many novel therapies are currently being used for which little data exists on their effect on morphology and genetics.  When evaluating myeloid neoplasms after the initial diagnosis, it is recommended to express the diagnosis in comparison to the initial presentation and provide information that allows application of current treatment response guidelines. Data in pathology reports should be presented as objectively and quantifiably as possible.  It is hoped that accumulated data, particularly on effects of novel therapies, can inform diagnosticians on the interpretation of changes in morphology and genetics, and how these changes can be used to guide therapy. 

 

 

References:

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2.     Zeidan AM, Platzbecker U, Bewersdorf JP, et al. Consensus proposal for revised International Working Group 2023 response criteria for higher-risk myelodysplastic syndromes. Blood. 2023 Apr 27;141(17):2047-2061.

3.     Faria C and Tzankov A. Progression in myeloid neoplasms: beyond the myeloblast. Pathobiology 2024;91:55-75.