Large granular lymphocytic leukemia (LGL) is a rare type of chronic leukemia that affects white blood cells known as lymphocytes. There are three types of large granular lymphocytic leukemia. Two types grow slowly and act like chronic diseases. The third type is more aggressive. Healthcare providers can treat large granular lymphocytic leukemia, but they can’t cure it.
Large granular lymphocytic leukemia (LGL) is a rare type of chronic leukemia that affects white blood cells known as lymphocytes. Lymphocytes fight viruses and make antibodies that help fight infection.
There are two types of large granular lymphocytic leukemia —T-cell large granular lymphocytic leukemia (T-LGL) and chronic lymphoproliferative disorder of NK-cells (CLPD-NK). These conditions start in white blood cells called cytotoxic T-cells or natural killer cells. Both types of large granular lymphocytic leukemia grow slowly. They typically affect people age 60 and older. Healthcare providers can treat LGL, but the condition sometimes comes back and can become a chronic health issue.
LGL is a type of chronic lymphocytic leukemia that occurs when certain T-cells and natural killer cells mutate, becoming abnormal cells that keep your bone marrow from producing normal blood cells. People with LGL often develop neutropenia, meaning they produce low numbers of granulocytes (the most common white blood cells) and have an increased risk of infection. They may also develop anemia, which happens because LGL cells affect red blood cell production.
Who does it affect?
Large granular lymphocytic leukemia is very rare, affecting 1 in 1 million people across the world. Most people are in their 60s when they’re diagnosed.
People may have this condition and never have symptoms. One study showed about one-third of people with LGL didn’t have any symptoms when they were diagnosed. Instead, they learned they had LGL because blood tests showed they had unusually low red blood levels or low levels of neutrophils (a type of granulocyte). In some cases, people are diagnosed with LGL because they’re being treated for blood disorders and they have symptoms that healthcare providers link to large granular lymphocytic leukemia. People who do have symptoms often have the following:
Many people with LGL have autoimmune diseases, particularly rheumatoid arthritis. Other common conditions are:
Healthcare providers aren’t sure what causes the condition, but they believe there’s a link between this type of leukemia and immune responses, autoimmune diseases or other cancers:
Healthcare providers typically do blood tests and genetic analyses to diagnose this condition. Common tests may include:
They may do other tests, including bone marrow examinations, to rule out conditions including immunodeficiency, rheumatoid arthritis, myelodysplasia and myeloid mutations. They may also check immunoglobulin levels and monoclonal protein levels.
If you have T-LGL or CLPD-NK leukemia but don’t have symptoms, your provider may recommend watchful waiting. In watchful waiting, providers monitor your health, typically taking blood tests every few months and watching for signs of symptoms.
People who do have symptoms may receive immunosuppressive therapy and steroids. Healthcare providers may use one treatment after another or use low-intensity forms of treatment. Because LGL is a rare condition, people often seek out doctors who specialize in this disease.
No, you can’t. Healthcare providers don’t know the exact cause of large lymphocytic granular leukemia, so they can’t say how you might avoid it. That said people who have autoimmune diseases have an increased risk of developing this condition. If you have an autoimmune disease, ask your healthcare provider whether you should be concerned about developing LGL.
Most of the time, large granular lymphocytic leukemia is a chronic illness that isn’t fatal. About 75% of people with T-LGL leukemia and CLPD-LGL leukemia are alive five years after diagnosis. About 10% of people with these types of leukemia die of severe infections that are complications of leukemia.
If you have a type of large granular lymphocytic leukemia, you may not have symptoms but you should take steps like monitoring your overall health and having regular checkups. Regardless of whether you have symptoms, the following suggestions may be helpful:
In general, people treated for LGL can typically live normal lives and have the same lifespan as people who don’t have the condition. It’s important to remember that some people who have LGL already have serious blood disorders that affect their quality of life.
You should see your healthcare provider if you develop symptoms that may be signs your condition is getting worse. If you have symptoms and are receiving treatment, you should see your provider if you notice changes in your body, such as symptoms that are getting worse.
Large granular lymphocytic leukemia is a very rare illness. Here are some suggested questions that may help you learn more about LGL:
A note from Cleveland Clinic
Large granular lymphocytic leukemia (LGL) is a rare blood cancer that affects your white blood cells. You can have this condition but not notice any changes in your body that may be LGL symptoms. In some cases, people may not have symptoms for several years. Healthcare providers can’t cure the condition, but they have treatments to manage its symptoms. It may be alarming to hear you have an incurable illness. Your healthcare providers will understand why you may worry about what’s next. They’ll be glad to explain what you can do now to support your health and what you can expect when you do have symptoms. Knowing what to expect may help you feel more confident about living with LGL.
Last reviewed by a Cleveland Clinic medical professional on 09/03/2022.
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