What laboratory tests are used to monitor Chronic Lymphocytic Leukemia (CLL)?

From the Guidelines

Monitoring of Chronic Lymphocytic Leukemia (CLL) should include regular complete blood counts (CBCs) with differential, comprehensive metabolic panels, lactate dehydrogenase (LDH) and beta-2 microglobulin levels, immunoglobulin levels, and genetic testing for markers like del(17p) and TP53 mutations, as these parameters help assess disease progression, potential complications, and guide therapy selection, as recommended by the international workshop on chronic lymphocytic leukemia 1.

Key Laboratory Tests for CLL Monitoring

• Complete blood counts (CBCs) with differential to track lymphocyte counts, hemoglobin levels, and platelet counts, which is essential for assessing disease progression and potential complications like anemia or thrombocytopenia 1
• Comprehensive metabolic panels to evaluate liver and kidney function, particularly important when patients are on treatment
• Lactate dehydrogenase (LDH) and beta-2 microglobulin levels as prognostic markers, with elevated values often indicating more aggressive disease, as noted in the national cancer institute-sponsored working group guidelines for chronic lymphocytic leukemia 1
• Immunoglobulin levels to monitor for hypogammaglobulinemia, which increases infection risk in patients with CLL
• Genetic testing for markers like del(17p) and TP53 mutations to influence therapy selection, as recommended by the international workshop on chronic lymphocytic leukemia 1

Additional Monitoring Considerations

• Bone marrow examinations are typically done at diagnosis and when assessing response to therapy, as outlined in the guidelines for the diagnosis and treatment of chronic lymphocytic leukemia 1
• For patients on specific therapies, additional monitoring may be required, such as regular ECGs for those on BTK inhibitors like ibrutinib due to potential cardiac effects
• Monitoring should occur every 3-6 months for stable patients, but more frequently during active treatment or disease progression, to allow for timely intervention when disease status changes or treatment-related complications arise 1

From the Research

Laboratory Tests for Monitoring Chronic Lymphocytic Leukemia (CLL)

The following laboratory tests are used to monitor CLL:

• Blood counts, including complete blood cell count (CBC) to assess hemoglobin and platelet levels 2, 3, 4, 5
• Blood smears to identify clonal B-cell population 4, 5
• Immunophenotyping of circulating B-lymphocytes to identify CD5 antigen and B-cell markers 2, 4, 5
• Flow cytometry to confirm the expression of typical surface markers CD5, CD19, and CD23 2
• Direct antiglobulin test (DAT) to predict the development of autoimmune hemolytic anemia (AHA) 6

Imaging Studies

Imaging studies used to assess the degree of lymphadenopathy or organomegaly include:

• X-ray of the chest 2
• Ultrasound of the abdomen 2
• CT scan 2

Staging Systems

Two prognostic staging systems exist:

• Rai staging system 3, 4, 5
• Binet staging system 2, 3, 4, 5

Biomarkers

Various biological and genetic markers have prognostic value, including:

• Deletions of the short arm of chromosome 17 (del(17p)) 4, 5
• TP53 mutation 4, 5
• CD38, CD25, and double-positive CD56/CD117 expression 3
• Platelet/lymphocyte ratio (PLR) 3
• Neutrophil/lymphocyte ratio (NLR) 3