The CBC, white blood cell differential, and blood smear examination are what initially alert us to the possibility of a leukemia diagnosis in the laboratory. The laboratory professional will typically note elevated white counts, immature cells and cell morphologies, and possibly abnormal red cell or platelet counts. The white cell differential can give a clue as to whether the leukemia is acute or chronic, and myeloid or lymphocytic.
Cell staging and differentiation between myeloid and lymphocytic is an important first step, as is determining if the leukemia is acute or chronic.
Further laboratory samples will then be evaluated. Samples will include bone marrow biopsy and aspirations, and less commonly cerebrospinal fluid or tissue samples. Bone marrow morphologic evaluation is typically done by a pathologist; thereafter, flow cytometry, cytogenetic analysis, and genetic studies will be performed for the definitive diagnosis.
