Normal blood cells (left) vs. those affected by leukemia.

You’re feverish and fatigued. Your joints ache, and your lymph glands have swollen. Sounds like you have signs of the flu or any number of infections. But they’re also common leukemia symptoms.

In general terms, leukemia is cancer of your body’s blood-forming tissues, such as the bone marrow. Signs of leukemia vary, depending on the type of cancer you have; in some cases, leukemia causes no symptoms early on.

Since many leukemia symptoms are vague and may be caused by other conditions—cancerous and non-cancerous—it’s important to have them evaluated by your physician. A prompt, accurate diagnosis means an earlier start to treatment that may save your life.

What Is Leukemia?

Leukemia results in overproduction of cancerous white blood cells that don’t function properly. Eventually, leukemia cells crowd out and inhibit the formation of normal red blood cells, platelets, and healthy white blood cells, which fight infection.

Acute forms of leukemia include two main subtypes: acute lymphocytic leukemia and acute myeloid leukemia. The acute forms progress more rapidly and, left untreated, can result in death in weeks or months. However, some acute leukemias may respond more favorably to treatment and, in many cases, can be cured.

Chronic leukemias tend to advance more slowly and may not cause problems until later stages—oftentimes, patients can live for many years—but they tend to be more difficult to cure than acute forms. The two main subtypes are chronic lymphocytic leukemia and chronic myeloid leukemia.

Know the Signs: Common Leukemia Symptoms

Leukemia symptoms vary depending on whether you have an acute or chronic form of the disease. Early acute leukemia symptoms may resemble those of the flu, and include fever, achy joints, fatigue, and swollen lymph glands.

As acute leukemia progresses and platelet production wanes, clotting problems may develop, causing easier bruising or bleeding, or the formation of tiny red spots on the skin known as petechiae. Declines in healthy white blood cells may reduce your ability to fight infections.

Many people with chronic leukemias, particularly those in the early stages, have no symptoms and are diagnosed incidentally on the basis of an elevated white blood cell count on blood tests performed for another reason. Chronic lymphocytic leukemia symptoms include fever, dizziness, fatigue, infections, excessive sweating, night sweats, swollen lymph glands, loss of appetite and related weight loss, and excessive bruising and bleeding.

Chronic myeloid leukemia symptoms include fever, fatigue, night sweats, weight loss, and bone pain. Also, patients with either form of chronic leukemia may develop a sense of fullness in the belly, even after eating little food, as well as pain or pressure in the upper left side of the abdomen caused by an enlarged spleen.

Finding the Cause

Your physician will review your medical history, perform a physical exam to look for leukemia symptoms, and order blood tests to measure levels of white blood cells and platelets. If the test results are abnormal, your doctor may recommend a bone marrow biopsy to help identify the type of leukemia you have and to guide treatment decisions. In some cases, a lumbar puncture may be necessary to determine if leukemia cells have spread to the cerebrospinal fluid, which nourishes the spinal cord and brain.

All people with chronic myeloid leukemia and about one-quarter of adults with acute lymphocytic leukemia have a genetic abnormality known as BCR-ABL, which leads to production of a protein that promotes cancer growth. As such, if testing reveals that you have one of these forms of leukemia, your doctor will probably order genetic testing to identify BCR-ABL. This testing is important because your physician can prescribe treatments that specifically target BCR-ABL and its related protein.

Originally published in 2016, this post is regularly updated.