Asymptomatic patient with lymphocytosis unlikely to die soon
DEAR DR. ROACH: I’m 71 years old. In 2021, lymphocytosis was found during my pre-op workup for breast cancer. I had a successful lumpectomy and radiation, and I am on a five-year course of anastrozole.
After reviewing my prior complete blood counts, lymphocytosis was found leading back to 2018. It was thought to be due to an infection, so no other tests were done at the time. I have now had a flow cytometry done, with findings of the IGHV mutation. I received a “favorable prognosis.” But there was no definitive diagnosis of chronic lymphocytic leukemia (CLL) by my oncologist. As he states, I have “not converted” and have no symptoms of fatigue, an enlarged spleen, or enlarged lymph nodes.
I find myself waiting for the other shoe to drop, and I’m having a difficult time enjoying the breast cancer survival I am so grateful for. Any information you can provide about whether CLL is inevitable in patients with lymphocytosis is very much appreciated. Also, please comment on the expected quality/length of life if CLL is diagnosed, including the need for chemotherapy. — E.B.
ANSWER: “Lymphocytosis” is a condition where the body’s lymphocyte count is increased. There are two big categories of white blood cells: lymphocytes and granulocytes. When the lymphocyte count exceeds 4,000, it’s considered “lymphocytosis.”
There are two major classes of lymphocytes: B cells and T cells. While it is true that a high lymphocyte count can be due to infections, it sounds like yours wasn’t recognized as persistent. With lymphocytosis having been present for five years, there is a concern for a primary bone marrow disease, the most common of which is CLL. With CLL, there is a count of 5,000 or more B cells by definition. Since you have lymphocytosis, but not CLL, you must have at least 4,000 lymphocytes but less than 5,000 B cells.
The word “leukemia” literally means too many white cells in the blood, but leukemias are a large and diverse group of blood cancers. It’s a scary word, but CLL is highly variable. Fifty percent of people with CLL will live more than 10 years from the time of diagnosis, and some will live 30 or more years before dying, often of something unrelated to leukemia.
The prognosis for CLL depends on many factors. Most CLL found now is due to routine blood testing that reveal high white blood cell counts. When a person has no symptoms and, like you, no enlarged spleen or lymph nodes, they are in a favorable prognosis group. If a person does have symptoms, it isn’t as good of a prognosis. Leukemia cells “crowd out” the other healthy cells in the bone marrow, leading to anemia and thrombocytopenia, which are also less-favorable prognoses.
People who have gene mutations in the IGHV region receive a surprisingly improved prognosis compared to people who do not have mutations. These genetic mutations are always looked for, since they affect the choice of chemotherapy, if needed.
For you, you have had lymphocytosis for at least five years and have not progressed to CLL. You have no risk factors due to symptoms, and you haven’t told me about low platelets or red blood cells. Even if you were diagnosed with CLL today, you would be more than 90% likely to have at least a 10-year lifespan. You seem to be in the 30% or so of people with CLL who have a benign course for 10-20 years. Drive carefully, eat well, and get all your vaccines, since you are not likely to die from CLL.