What are the specific stages of chronic lymphocytic leukemia (CLL), and how does CLL progress? Dr. Matthew Davids details the stages of CLL and indications for when it’s time to treat the condition.
Dr. Matthew Davids is Director of Clinical Research in the Division of Lymphoma at Dana-Farber Cancer Institute. Learn more about Dr. Davids here.
Okay. So, how does CLL progress? When do you know when it’s time to treat?
The stages of CLL involve the progression of the disease. When we first meet patients, often they only have cells circulating in the blood, and that’s called stage 0 disease. It’s one of the few cancers where there’s actually a Stage 0 before even Stage I, and the reason for that is that many patients can go for years on Stage 0 disease. But as the burden of the CLL cells begin to accumulate in the body they can start to collect in their lymph nodes, and the lymph nodes can start to swell up whether it’s in the neck or the armpits or elsewhere. That’s stage I disease.
They can accumulate in the spleen, which is an organ in the abdomen. It’s kind of a big filter for your bloodstream, and as the filter traps more of these lymphocytes the spleen can slowly enlarge over time. That’s stage II disease.
And then finally, the CLL cells can get into the bone marrow, which is like the factory for making your blood cells. And if the factory floor gets all gummed up with CLL cells it can’t make the normal red cells, that’s called anemia. Or it can’t make the normal platelet cells, that’s called thrombocytopenia. And when we start to see those more advanced stages III and IV of CLL, that usually does require treatment. And what the treatment does is it clears out the factory floor and it allows for the normal machinery to make the normal blood cells again. So, that’s one of the more common reasons why treatment is needed is due to anemia and low platelets. Second reason can be if the lymph nodes or spleen get so bulky that they’re uncomfortable or threatening organs internally. We want to treat before that becomes a real threat.
And then, the third thing that usually happens as the disease progresses, patients can develop some symptoms, what we call constitutional symptoms. These can be things like unintentional weight loss, drenching night sweats that are happening on a consistent basis, and those sorts of things. So, if that’s happening at the same time as these other factors are progressing, those would be reasons to treat.
And notice that one thing I did not say is the white blood cell count itself.
That’s a common misconception. Some people think that as the white blood cell count goes higher – and people use all different thresholds, 100, 200 – that by crossing that threshold you need to start treatment. And in fact, that’s not the case. We have many patients whose white blood cell count can get very high but then it can kind of level off and plateau for a period of several years, and as long as they don’t meet those other treatment indications, they don’t need to be treated just based on the white count alone.