Ann Lab Med.  2019 May;39(3):311-316. 10.3343/alm.2019.39.3.311.

Reclassification of Acute Myeloid Leukemia According to the 2016 WHO Classification

• Jung J
• Cho BS
• Kim HJ
• Han E
• Jang W
• Han K
• Lee JW
• Chung NG
• Cho B
• Kim M
• Kim Y

• KMID: 2431609
• DOI: http://doi.org/10.3343/alm.2019.39.3.311

Abstract

We reviewed our leukemia database to reclassify 610 patients previously diagnosed as having acute myeloid leukemia (AML) according to the updated 2016 WHO classification. Nine patients were categorized as having myelodysplastic syndrome and myeloid neoplasms with germline predisposition. AML with recurrent genetic abnormalities accounted for 57.4% (345/601) of the patients under the 2016 WHO classification. AML with mutated NPM1 was the most common form (16.5%), with the majority associated with monocytic differentiation (63.6%). AML with double CEBPA mutations accounted for 8.3% of these cases, and the majority were previously diagnosed as AML with/without maturation (78.0%). These newly classified mutations were mutually exclusive without overlapping with other forms of AML with recurrent genetic abnormalities. AML with mutated NPM1 and AML with myelodysplasia-related changes comprised the oldest patients, whereas AML with RUNX1-RUNX1T1 included the youngest patients. The leukocyte count was highest in AML with mutated NPM1, and the percentage of peripheral blood blasts was the highest in AML with double CEBPA mutations. Our results indicate that implementation of the 2016 WHO classification of AML would not pose major difficulties in clinical practice. Hematopathologists should review and prepare genetic tests for the new classification, according to their clinical laboratory conditions.

Keyword

2016 WHO classification; Acute myeloid leukemia; NPM1; CEBPA

MeSH Terms

Classification*
Humans
Leukemia
Leukemia, Myeloid, Acute*
Leukocyte Count
Myelodysplastic Syndromes

Figure

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  Fig. 1 Distribution of subtypes in AML patients classified according to 2016 WHO classification.Abbreviations: AML, acute myeloid leukemia; N, number of patients (%); dm, double mutation; MRC, AML with myelodysplasia-related changes; M0, AML with minimal differentiation; M1, AML without maturation; M2, AML with maturation; M4, acute myelomonocytic leukemia; M5, acute monoblastic and monocytic leukemia; APMF, acute panmyelosis with myelofibrosis; TAM, transient abnormal myelopoiesis associated with Down syndrome; TRMN, therapy-related myeloid neoplasms.

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