Leukemia, or leukaemia, is a kind of blood cancer that begins in cells of the bone marrow, the spongy tissue inside bones.

Bone marrow contains stem cells. In a healthy body, the stem cells develop into:

• Red blood cells, which help carry oxygen throughout the body
• White blood cells, which help fight infections
• Platelets, which help blood clot

Sometimes, those cells change and become leukemia cells, called blasts. As blasts multiply, they can affect the ability of normal cells to grow and function normally. Over time, leukemia can take over the bone marrow.

This means the body has fewer and fewer healthy white blood cells, red blood cells and platelets. That is what causes the symptoms of leukemia.

How is leukemia classified?

Leukemia is classified in two ways. First, the disease can be either chronic (slow-growing) or acute (more aggressive).

Second, leukemia is classified based on the types of leukemia cells present. This is determined by where the disease started. Lymphocytic leukemias start in lymphoid cells, and myelogenous leukemias start in myeloid cells.

The symptoms of leukemia vary, depending on type and how advanced the cancer is. Many of the symptoms look and feel like the flu or other common illnesses:

• Bleeding or bruising that occurs easily, including nosebleeds or tiny blood-like spots on the skin called petechiae
• Bone pain
• Excessive sweating
• Fatigue (extreme tiredness) or weakness
• Fever and chills
• Repeat infections
• Swollen lymph nodes, liver or spleen
• Weight loss for no apparent reason

Scientists don’t fully understand what causes leukemia. But some factors may include:

Cancer treatment: If you’ve had treatment for other types of cancer, you may be more at risk for leukemia.

• Exposure to chemicals: Exposure to certain chemicals is associated with some kinds of leukemia.
• Genetic disorders: Mutations in DNA, which may be passed down in families, can contribute to the development of leukemia.
• Smoking: Smoking cigarettes increases the risk of certain types of leukemia.

Penn hematologists have been pioneers in the latest treatments for blood cancers. They continue to lead the field with cutting-edge research and treatment of leukemia. When you choose us for leukemia care, you’ll find:

• A nationally recognized program: Penn is one of a few hematologic malignancy research programs in the country approved and funded by the National Cancer Institute.
• Expertise in each type of blood cancer: Our physicians are fellowship-trained hematologists (blood cancer specialists) who specialize in specific types of leukemia. So we have an expert for your individual needs. Our leukemia team leads the field, setting international leukemia guidelines and teaching other hematologists about the latest advances in leukemia treatments.

Support through the cancer journey: We’re here for our patients and families throughout leukemia care with comprehensive cancer support services. Your team includes hematologist-oncologists, oncology nurses, patient coordinators, nurse navigators, social workers, registered dieticians and financial advocates.

• Every treatment option: We offer every type of effective treatment for leukemia. Options range from traditionally effective treatments to cutting-edge immunotherapy and CAR T cell therapy.
• Cutting-edge research: Penn Medicine is a pioneer in research to find new treatments for blood cancers. Our patients have access to many leukemia clinical trials of the latest, most promising treatment options.

Accurate diagnosis is crucial to determining the most effective treatments. Our team has every advanced tool for precise leukemia diagnosis. We also have the expertise to interpret the complex results and what they mean for you.

We offer every effective option for leukemia treatment, including traditionally effective treatments, the newest advances and bloodless procedures. Throughout your treatment, our expert hematologists will carefully track your health and progress and adjust the plan as needed. Our patient coordinators and nurse navigators will make you’re your journey is as organized as possible — from your very first phone call to the day you achieve remission.