What is the diagnostic workup for leukemia (leukemia is a type of cancer that affects the blood and bone marrow)?

From the Guidelines

The diagnostic workup for leukemia should begin with a complete blood count (CBC) with differential, followed by a peripheral blood smear, bone marrow aspiration, and biopsy, as these procedures provide essential information for diagnosis, classification, and risk stratification 1. The workup for leukemia typically involves a combination of laboratory tests, imaging studies, and molecular analyses.

• Initial laboratory tests should include a CBC with differential, which often shows abnormal white blood cell counts, anemia, or thrombocytopenia.
• A peripheral blood smear should be examined for abnormal cells, and bone marrow aspiration and biopsy are essential diagnostic procedures, providing material for morphologic evaluation, flow cytometry, cytogenetic analysis, and molecular studies 1.
• Additional tests include comprehensive metabolic panel, lactate dehydrogenase (LDH), uric acid levels, and coagulation studies.
• Imaging studies such as chest X-ray or CT scan may be performed to assess for lymphadenopathy or organomegaly.
• Lumbar puncture is indicated in acute lymphoblastic leukemia or if neurological symptoms are present.
• Specific molecular tests like PCR for BCR-ABL1 in chronic myeloid leukemia or FLT3, NPM1, and CEBPA mutations in acute myeloid leukemia help determine prognosis and guide therapy.
• HLA typing should be performed early if stem cell transplantation is being considered, as recommended by the College of American Pathologists and American Society of Hematology guideline 1. This comprehensive evaluation allows for accurate diagnosis, classification, risk stratification, and treatment planning for patients with suspected leukemia, ultimately improving morbidity, mortality, and quality of life outcomes.
• The use of multicolor comprehensive flow cytometry panel to cover a diagnosis of B- or T-ALL, AML, or MPAL, as well as conventional karyotyping and FISH techniques, can provide valuable information for diagnosis and prognosis 1.
• The selection of specific molecular tests should be based on the subtype of acute leukemia, and the use of next-generation sequencing (NGS) may be considered in certain cases 1.

From the Research

Diagnostic Workup for Leukemia

The diagnostic workup for leukemia involves several steps, including:

• A complete blood count (CBC) to reveal leukocytosis and other abnormally elevated or depressed cell lines 2
• Examination of the bone marrow or peripheral blood to confirm the diagnosis 2
• Morphologic evaluation, immunophenotyping, and karyotype analysis, as well as molecular genetic testing, to establish a complete diagnosis of acute leukemia 3
• Bone marrow core biopsy, which may be essential or helpful in the workup of patients with chronic myeloid leukemia (CML) or acute myeloid leukemia (AML) 4, 5

Role of Bone Marrow Evaluation

Bone marrow evaluation plays a crucial role in the diagnosis and monitoring of leukemia, including:

• Documenting hypocellularity in response to induction chemotherapy in AML patients 5
• Assessing response to treatment and evaluating measurable residual disease in AML patients 5
• Identifying the disease phase or myelofibrosis in CML patients 4
• Characterizing bone marrow findings after treatment with arsenic trioxide in acute promyelocytic leukemia (APL) patients 6

Laboratory Testing and Reporting

The College of American Pathologists and the American Society of Hematology have established guidelines for the diagnostic and prognostic evaluation of acute leukemia samples, including:

• Recommendations on what clinical and laboratory information should be available as part of the diagnostic and prognostic evaluation 3
• Guidelines on what types of testing should be performed routinely, where such testing should be performed, and how the results should be reported 3