Enzyme stains, also known as histochemical stains, are utilized for myeloid and monocytic cellular differentiation in acute leukemia. Application of histochemical stains by the pathologist can change the classification of the disease. The classification is either acute myelomonocytic leukemia (AMML) or acute myeloid leukemia (AML). Currently, the classification of acute leukemia is made with the aid of immunophenotyping and cytogenetics. Laboratories that do not readily have access to immunophenotyping may choose to utilize histochemical staining instead. Examples of histochemical stains include:
- Napthol-ASD chloroacetate esterase
- Acid phosphatase
- α-Napthyl acetate esterase
- Myeloperoxidase
- α-Napthyl butyrate esterase
