What is CLL?

Although I have already posted about possible Chronic Lymphocytic Leukemia (CLL) treatments, I have left out some background information on what CLL is, who it affects, and what the requirements for remission are.

CLL is the most common form of leukemia in Europe and North America, and is mostly only found in older adults, the median age for diagnosis being seventy years in males and seventy-four in females. Since it is a chronic disease, it almost never affects children, and is fairly uncommon for individuals under fifty years old. CLL can start when there is a mutation in the DNA of one marrow cell and then this marrow cell matures into a B lymphocyte. This malignant B lymphocyte or B cell begins to proliferate uncontrollably, which is called lymphocytosis, and hinders the production of other blood cells, such as red blood cells, causing anemia. The cluster of lymphocytes is what causes lymph node swelling because lymph nodes are areas of high lymphocyte concentration. In order for a patient to be diagnosed with CLL, there must be at least 5x10^9 B lymphocytes in a sample of the patient’s peripheral blood and there are other ways to diagnose a patient.

In a previous blog post, I went over various CLL treatments and their general mechanism of action and those treatments are of course to try to achieve cancer remission. As a patient continues through their long battle with cancer, he or she has blood drawn regularly and that blood is examined in a lab to monitor blood cell count. Since CLL is a proliferation of leukemic B cells, the main goal of treatment is to lower the amount of B cells in a patient’s peripheral blood back to normal amounts. For a patient to have complete remission, he or she must have a lymphocyte count in peripheral blood below 4x10^9, neutrophil count above 1.5x10^9, platelet count above100x10^9 hemoglobin above 100 G/ L, lymph nodes no bigger than 1.5 cm in diameter, and a non-significant enlargement of the spleen two months after active therapy has been completed. Many patients don’t ever reach complete remission, and instead have relapsed or refractory CLL. Refractory CLL means that the patient had treatment failure and a recurrence of symptoms within six months of treatment completion and relapse refers to a patient who had reached complete or partial remission, yet begins to develop symptoms more than six months of treatment completion.

Thank you for taking time out of your day to read my blog once again! If you have any questions about what CLL is, please leave a comment below. Have a great day!