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Cytogenetic Testing—Checking for Philadelphia Chromosomes

Cytogenetic Tests

• Achieving and maintaining a complete cytogenetic response (CCyR) is the goal of treatment
• Cytogenetic testing is important because it examines your cells for the Philadelphia chromosome—the telltale sign of chronic myeloid leukemia (CML)
• Cytogenetic testing is more sensitive than hematologic testing. There are 2 types of cytogenetic testing:
• Conventional cytogenetic testing uses a bone marrow sample
• Fluorescence in situ hybridization (FISH) is a more sensitive test of a blood or bone marrow sample
• Two types of procedures—aspiration and biopsy—are available to take samples of your bone marrow. Bone marrow testing is important because it can detect changes that cannot be seen in blood samples. Ask your nurse or doctor about these procedures
• Samples are examined under a microscope to count the number of Philadelphia chromosomes and to detect other changes to your chromosomes
• Cytogenetic tests can determine if you have chronic myeloid leukemia (CML) and measure your response to treatment

Complete Hematologic Response (CHR)

Complete Cytogenetic Response (CCyR)

Complete Molecular Response

Adapted from Löwenberg B, et al. Minimal residual disease in chronic myeloid leukemia. N Engl J Med. 2003:1399-1401.

• As you continue treatment and achieve a complete cytogenetic response, picture the reduction in the number of CML leukemia cells by using this triangle

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