NCCN Guidelines for Patients® | Chronic Lymphocytic Leukemia
16 NCCN Guidelines for Patients ® : Chronic Lymphocytic Leukemia, 2019 2 Treatment planning Genetic tests LDH LDH ( l actate d e h ydrogenase) is a protein that is in most cells. Dying cells release LDH into blood. Fast- growing cells also release LDH. High levels may be a sign that treatment may be needed now or soon. Quantitative immunoglobulins Immunoglobulins (also called antibodies) are Y-shaped proteins made by immune cells. They help your body detect germs and other threats. Quantitative immunoglobulins measure the amount of 3 types––IgG, IgA, and IgM––in blood. Some people with CLL have low levels of antibodies before cancer treatment. They may be sick often. Levels can also drop during cancer treatment. Lab results are used to decide if you need treatment to prevent or cure infections. Uric acid Uric acid is released by cells when they break down and die. Too much uric acid in the body is called hyperuricemia. You may have a high level of uric acid before starting treatment. Levels can be high due to kidney disease or other health problems. Genetic tests Genetic tests assess for abnormal changes in genes and chromosomes in CLL cells. Such changes are not present at birth. Genetic tests are performed by pathologists. It often takes several days before the lab results are known. Results are used to assess the outcome (prognosis) of CLL and plan treatment. FISH It is very common for CLL cells to have abnormal chromosomes. Chromosomes that commonly have defects are chromosomes 11, 12, 13, and 17. FISH is a test that detects abnormal chromosomes and genes. It can be done using either blood or bone marrow cells. Missing (deleted) parts of chromosomes 11 or 17 used to be signs of a poor outcome, but now treatment is better. A good outcome is linked to deleted parts of chromosome 13, if it is the only abnormal chromosome. Three copies of a chromosome instead of the normal two is called trisomy. Trisomy 12 is linked to neither a poor nor a good outcome. Karyotype A karyotype is a picture of chromosomes. It shows if there is a defect in the size, shape, and number of chromosomes. See Figure 4 . A blood or bone marrow sample can be used. This lab test adds chemicals to the sample to start cell growth. For CLL, a chemical called CPG should be used. A “complex karyotype” is linked to a poorer outcome. A complex karyotype is 3 or more unrelated defects in chromosomes that occur in more than one cell. The presence of a complex karyotype may affect your treatment options. Pathology report All lab results are included in a pathology report. This report will be sent to your doctor. Ask him or her for a copy. Your doctor will review the results with you. Take notes and ask questions.