American Society for Clinical Pathology (ASCP) Technologist in Cytogenetics certification (ASCP CG) Practice Test

In the context of AML types, which statement about differentiation is accurate?

1. Both M0 and M1 exhibit clear differentiation between cells

2. M0 shows complete differentiation while M1 is undifferentiated

3. M0 is minimally differentiated while M1 is not differentiated

4. M1 is known for its unique differentiating characteristics

The correct answer is: M0 is minimally differentiated while M1 is not differentiated

In acute myeloid leukemia (AML), the classification of different subtypes frequently addresses the degree of differentiation of the malignant cells. In this context, M0 and M1 represent two subtypes of AML that differ notably in their level of differentiation. M0 is characterized as minimally differentiated, meaning that the leukemic cells exhibit a very primitive appearance and do not show significant signs of maturation. These cells are largely undifferentiated, making it difficult to determine the lineage of the cells under light microscopy, and they do not exhibit the specific characteristics associated with more differentiated myeloid cells. On the other hand, M1 is classified as poorly differentiated, but it typically shows some more features of myeloid differentiation compared to M0. M1 cells may sometimes present with certain characteristics typical of myeloid lineage, such as the presence of myeloperoxidase activity, although they also largely lack complete differentiation. The distinguishing aspect of these classifications lies in the degree of cell maturation, where M0 represents a higher level of immaturity than M1. Therefore, the accurate statement regarding differentiation is that M0 is minimally differentiated while M1 shows some signs of myeloid differentiation, aligning with the correct answer. Understanding this distinction is crucial