Leukemia is a type of cancer that affects the blood cells, so it doesn’t cause tumors to form like in other cancers. It usually impacts white blood cells.
There are several types of leukemia. All types of leukemia can affect people of any age, but some types are more common in older adults. Diagnosis, treatments, and outlook may also be different in older adults with leukemia than in children or younger adults with leukemia.
There are four main types of leukemia. The types are based on whether the leukemia spreads slowly (chronic leukemias) or quickly (acute leukemias) and where the leukemia starts.
The four main types are:
- Acute lymphocytic leukemia (ALL). ALL forms in immature lymphocytes, a type of white blood cell found in bone marrow. ALL tends to grow and spread quickly. It’s relatively rare and mostly affects children.
- Acute myeloid leukemia (AML). AML starts in the bone marrow in nonlymphocytic white blood cells. It often grows and spreads quickly. AML is a common type of leukemia in older adults, but it’s still relatively rare compared to other forms of cancers. The average age of diagnosis is about 68 years old, and people under age 45 are very rarely diagnosed with AML.
- Chronic lymphocytic leukemia (CLL). CLL starts in the lymphocytes and usually progresses slowly over time. It’s the most common type of leukemia in adults. CLL is usually diagnosed in people around age 70 and is very rarely diagnosed in people under 40 years old.
- Chronic myeloid leukemia (CML). CML occurs when your bone marrow makes too many myeloid white blood cells. CML is slow-growing. The average age at diagnosis is 64 years old, and about half of the cases are found in people 65 years and older.
AML is more common in older adults because it’s often caused by genetic mutations. These mutations may not cause cancer at first, but they can build up over time and lead to acute leukemia.
Chronic leukemias are more commonly diagnosed in older adults, mainly because they don’t often cause symptoms in early stages. They are also slow-growing, and cancerous cells typically build up gradually over time as people age. Therefore, people tend to be older when they’re diagnosed with chronic leukemia.
Some of the most common symptoms of leukemia in older adults include:
- weight loss
- night sweats
- loss of appetite
- shortness of breath
- bruising easily
- chronic infections
- bleeding easily, such as nosebleeds or bleeding gums
- swelling or feeling fullness in your abdomen
- joint and bone pain
- enlarged lymph nodes
Again, it’s important to remember that chronic leukemia may not show symptoms until much later in the course of the disease.
A healthcare professional may be able to identify leukemia through a blood test called a complete blood count. This is a routine test, so they may identify an issue even before you have symptoms. In this case, the test will show too many white blood cells or cells that look out of the ordinary.
If your doctor suspects you have leukemia, they might recommend some of these additional tests:
- physical exam to see if your lymph nodes, liver, or spleen are swollen (enlarged)
- bone marrow biopsy, in which tissue is taken from bone marrow in your hip to see if there are leukemia cells in your bone marrow and to figure out what type of leukemia you may have
- chest X-ray
- PET scan to stage the leukemia, which means finding out how much the cancer has spread and progressed
- chest CT scan
- cytogenetics, which looks at chromosomes in blood or bone marrow samples and can indicate the type of leukemia you have
- spinal tap, which checks spinal fluid for leukemia cells
- ALL doesn’t have stages like other types of cancer, but the doctor will take into account your type ALL (B cell or T cell) when thinking about treatment options.
- AML is classified in subtypes, rather than symptoms, using the French-American-British classification system. It includes eight subtypes based on certain blood cell characteristics, such as number of leukemia cells and type of genetic mutations.
- In the United States, CLL is usually staged using the Rai system, which includes stages 0 to IV. The stages are based on the amount of lymphocytes in your blood and bone marrow, as well as spleen, lymph nodes, and liver involvement.
- CML has three stages — chronic, accelerated, and blast. These stages are based on:
- blood cell counts
- the number of blast cells you have
The type of treatment you receive will be based on several factors, including your overall health, the type of leukemia, and your age.
Leukemia in older adults is often harder to treat than leukemia in younger people. This is because:
- Older people tend to have more comorbidities, or coexisting conditions.
- Higher doses of chemotherapy are too harsh for older adults.
- People become more prone to infections as they age.
- Older people have more cellular mutations.
However, leukemia in older adults can still be successfully treated and even cured. Treatment options are discussed in the following sections.
Watch and wait
If you have a chronic type of leukemia and are relatively healthy, your doctor may recommend watching and waiting before beginning treatment. Because some treatments may be harmful to older adults, this helps make sure you’re not treated until you need to be.
Chemotherapy is a common treatment for leukemia in people of all ages. If you’re otherwise healthy and have the necessary social support, your doctor may recommend intensive chemotherapy, which has a higher chance of curing your leukemia. However, low-intensity chemotherapy can have very good results as well and may be used if you have other health issues.
Stem cell transplant
Stem cell transplants may not be offered to older people often, but they can be very successful in preventing leukemia relapse. A relapse is when your leukemia returns after treatment has ended. You need to be generally healthy (besides the leukemia) to have a stem cell transplant.
In many cases, stem cell transplants are used for people whose cancer is caused by many genetic mutations. This is because cancers with fewer mutations or with other causes are more likely to respond well to chemotherapy, which is usually less risky.
There are several types of medications available for treating leukemia, including immunotherapies and kinase inhibitors. Immunotherapies help your immune system kill cancer cells, while kinase inhibitors help stop the cancer from growing.
The outlook for people with leukemia depends on many factors, including:
- the stage at which you’re diagnosed
- your age
- the type of leukemia you have
- other health issues you have
Targeted therapies such as immunotherapies can increase survival rates of people with acute leukemias. While some research suggests targeted therapies can increase survival rates to approximately 10 months after diagnosis, these therapies are new, so less is known about them.
Different types of drugs are approved for different types of leukemia. Because these drugs work on specific pathways in your body, they may be safer than other therapies. Your doctor may also recommend adding a medication to chemotherapy for better results.
For chronic leukemias, treatment is usually used to control the spread of cancer and manage your symptoms. It’s generally not expected to cure the leukemia, although you can live for many years with chronic leukemia. If you go into remission after treatment, a stem cell transplant can further increase your survival rate.
Here is a breakdown by age of the 5-year survival rates for people with CLL, according to the advocacy group Cancer Research UK:
- ages 60 to 69: nearly 90 percent
- ages 70 to 79: more than 80 percent
- ages 80 and older: about 65 percent
Leukemia is more commonly diagnosed in older adults than in adults of other ages. Your doctor will take into account your overall health, type of leukemia, age, and other factors when forming a treatment plan.
While the median survival rate for acute leukemia can be daunting, there are new treatments being tested that may improve survival rates. People with chronic leukemia can live many years with this disease and successfully manage their symptoms. Talk with your doctor about your treatment goals to find what options are best for you.