The Northside Hospital Department of Pathology includes eighteen board-certified pathologists with a broad range of subspecialty expertise. Six fellowship-trained hematopathologists and one fellowship-trained molecular pathologist are part of the pathology group. These physicians specialize in the diagnosis of hematolymphoid diseases, with acute leukemia being among the most critical of these diagnoses.

The diagnosis of acute leukemia requires integration of morphologic, immunophenotypic, cytogenetic, molecular genetic, and clinical findings. These data are all essential in providing the patient with the correct diagnosis, adding important prognostic information, and, increasingly, impacting therapeutic decisions. The NH-Leukemia Program routinely tests for a number of different gene mutations that may impact diagnosis, prognosis, and therapy as part of the initial workup of new acute leukemia patients. Depending on the patient’s presumptive diagnosis, these may include;

• PCR-based mutational analysis for FLT3-ITD and FLT3-TKD.

• FISH studies for large scale rearrangements of PML-RARA, BCR-ABL1, MLL, and others

• Next-generation sequencing, which covers a large panel of gene mutations,

The hematopathologists work to expediently evaluate and integrate data in order to proceed with important clinical decisions.

In the process of making a diagnosis of acute leukemia, the hematopathologists:

• Review the morphology of peripheral blood, bone marrow aspirate, and bone marrow core biopsy samples, looking for increased numbers of immature cells (blasts and blast equivalents) as well as other essential morphologic findings, including dyspoiesis.

• Look for morphologic clues that may impact immediate clinical decision-making or suggest alternative testing that may be needed.

• Review flow cytometric immunophenotyping data, integrating this information into the diagnostic algorithm.

• Utilize special studies, including immunohistochemistry, in-situ hybridization, and cytochemistry, as needed for appropriate disease categorization.

• Review cytogenetic and molecular genetic data that may impact the diagnosis or prognosis.

Ongoing monitoring of the blood and bone marrow of patients with acute leukemia is also an important role for the hematopathologists. All of the techniques discussed above may be essential in the follow-up setting. Hematopathologists recognize morphologic and immunophenotypic changes that may be induced by therapy and/or early signs of recurrent disease. Understanding these findings is critical in separating therapeutic impact and marrow recovery from residual or relapsed disease.