Complete Blood Count (CBC) Test Overview

The complete blood count, or CBC, is a common blood test that measures the different cells in your blood, including red blood cells, white blood cells, and platelets, and helps your healthcare team evaluate your overall health.

The BCL6 gene rearrangement test is a specialized genetic test that looks for changes in the BCL6 gene. BCL6 (B-cell lymphoma 6) is a gene that helps control how B-cells (a type of white blood cell) grow and function. Sometimes this gene can become rearranged, which means its structure has changed. This test uses a technique called Fluorescence In Situ Hybridization (FISH) to detect whether these rearrangements are present in your blood or tissue sample.

The test is performed by drawing a small sample of blood, usually from a vein in your arm, using a thin needle. The procedure takes only a few minutes, and the sample is then sent to a laboratory for analysis.

For this test, a sample of your blood or tissue (often from a lymph node biopsy) will be collected. In the laboratory, scientists use special fluorescent probes that attach to the BCL6 gene. If the gene is rearranged, these probes will show a different pattern under a fluorescence microscope compared to a normal gene. The test does not use radiation and is generally safe with minimal risks.

Your doctor may order this test as part of a routine checkup, to help investigate symptoms such as fatigue, weakness, fever, or unusual bruising, or to monitor an existing condition such as anemia, infection, or a blood disorder.

Your doctor may order this test if you have symptoms or findings suggesting a B-cell lymphoma, such as enlarged lymph nodes, unexplained weight loss, fever, or night sweats. The test helps confirm the diagnosis and determine the specific type of lymphoma. It may also be used to help predict how the disease might behave and guide treatment choices.

Results within the normal reference ranges usually show no signs of blood-related problems. Abnormal values may suggest conditions such as anemia, infection, inflammation, or clotting disorders, and your doctor will explain what your specific results mean for you.

Results are typically reported as either 'rearranged' (positive) or 'not rearranged' (negative). A positive result means a BCL6 gene rearrangement was detected in your sample. This finding is associated with certain types of B-cell lymphomas, most commonly diffuse large B-cell lymphoma (DLBCL). Your doctor will interpret these results along with other test findings to make a complete diagnosis and determine the best treatment plan.