We can learn a lot about CLL just by blood tests. Even from a basic blood count, which is done routinely in primary doctor's offices. Looking at those numbers, we can get a pretty strong suspicion that CLL is present. we can get a pretty strong suspicion that CLL is present. To confirm it, though, we have to do some more advanced testing on blood cells. There's a test called the flow cytometry where cells are sorted by surface proteins and other markers that allow the machine to recognize one cell from another
and to recognize an abnormal population of lymphocytes. So it's a question of having more lymphocytes than expected, but also having them be slightly different than than healthy lymphocytes. When these tests make it clear—the nature of the CLL, We can sometimes really know all we need to know without doing the next, the more advanced tests, which would be a bone marrow biopsy. All blood cells originate from bone marrow. And so to really understand some blood cancers, we need to look at the source and we need to take a sample from the inside of of a bone. Usually the pelvic bone, just because it's a very big one and it's safe and fairly easy to take a sample from. So some patients with CLL will end up having this procedure and that just depends on, you know, what questions remain unanswered after we do all the testing we can on the blood. But in some cases that's not necessary. But it all starts with blood tests, and that's the majority of the the monitoring we do for this disease is just from blood. People get referred for suspicion of CLL often from just having too many white blood cells, just a high white blood count. When we, and certainly in a hematology clinic, when we do those blood counts, we also ask for the differential, when we do those blood counts, we also ask for the differential, which is looking at the subcategories of white blood cells. And it's the lymphocytes that we're talking about in this disease. And there's a cutoff. So if you you need to have a lymphocyte count above a certain number So if you you need to have a lymphocyte count above a certain number to even be considered for having CLL. But then, that's not, that doesn't confirm it. We would, it would lead to the next test which would be flow cytometry. Chronic lymphocytic leukemia can be confirmed on the basis of blood tests alone. You sent the blood for a test called flow cytometry that looks at a panel of antigens present on the cells to make the diagnosis. You do not usually need to do a bone marrow biopsy to establish the diagnosis. So you can essentially get first a complete blood count, which shows that the type of white cell called lymphocytes are elevated above the normal range. And then you send the blood off to a specialized hematology lab where they look at the antigen expression on these lymphocytes by a technique called flow cytometry. And that is the confirmatory test. Then if we're talking about SLL which is found more in lymph nodes, we need to take a sample from a lymph node and that's also a form of a biopsy. These are done with needles generally. So this is a very tiny sample of tissue. And in cases where we don't get enough information from that, then we can ask a surgeon to take a larger biopsy. So SLL, you would do a lymph node biopsy usually and do the same flow cytometry test.
HealthTree • May 1, 2023
