Living with Leukemia

by Food and Drug Administration (FDA)

It wasn't the flu-like symptoms that sent Neil Keller to the hospital one night in January 1995. It wasn't even the crippling back pain that left him virtually immobilized. It was the odd red stripe that Kathy Keller noticed running down the back of her husband's calf that prompted his sudden trip to the emergency room.

Following his evaluation, the physical education teacher from Frederick, Md., learned that the red stripe was a blood clot. He also learned that he had leukemia and needed immediate medical attention.

"I hastily left our two young children in the care of their grandparents because Neil was being transported quickly by ambulance to a special cancer center in Baltimore," remembers Kathy Keller. "It happened just that quickly."

According to the American Cancer Society (ACS), about 30,000 new cases of leukemia were diagnosed in the United States in 2001. And even though it is thought of primarily as a childhood disease, the ACS says that leukemia strikes more adults than children. Anyone can get it, and like many forms of cancer, its cause is unknown. Certain risk factors, such as genetic conditions or adverse environmental exposure, are believed to increase the chances of developing the disease.

Survival is strongly linked to age at diagnosis and the type of leukemia. Fortunately, the overall five-year survival rate for people with leukemia has tripled over the past 40 years. In 1960, the rate was 14 percent. By the 1970s, it had reached 35 percent. Today, the overall five-year survival rate is 44 percent.

All forms of leukemia can be treated. In the last decade, several new drugs or new uses for existing drugs have been approved by the Food and Drug Administration to treat various types of leukemia. One of the most recent of these approved drugs — Gleevec (imatinib mesylate) — represents a new strategy in fighting one type of leukemia. It works by blocking the rapid growth of white blood cells.

But cancer experts say the best hope of a breakthrough that will greatly improve cure rates and duration of remission lies in understanding and controlling the abnormal molecular processes that lead to the development of all types of leukemia.

More Than One Disease

Leukemia is cancer of the blood cells. It is characterized by the uncontrolled growth of developing bone marrow cells. It is not a single disease, but a group of malignancies in which the bone marrow and blood-forming organs produce excessive numbers of white blood cells. White blood cells develop from a type of cell in the bone marrow called a stem cell. When the process of white cell maturation goes awry, leukemia results. Immature white cells prevent the normal production of all blood cells, including white blood cells, which fight infection. In most leukemias, an increased number of cancerous white blood cells are produced, causing the lymph nodes, liver, or spleen to enlarge.

Leukemias are classified by the type of white blood cell that has abnormal growth and by how fast the disease is progressing. Acute leukemia can be fatal within weeks or months without aggressive treatment. Abnormal blood cells that remain very immature, called "blasts," increase rapidly and the disease worsens quickly.

Chronic leukemia may produce no symptoms for years. Some immature cells may be present, but in general, these cells are more mature than those in acute leukemia and are able to carry out some normal cell functions. The number of blasts increases less rapidly than in acute leukemia, and as a result, chronic leukemia worsens gradually. Chronic leukemia can become acute leukemia.

Leukemia can arise in either of the two main types of white blood cells — lymphoid or myeloid. Leukemia that affects lymphoid cells is known as lymphocytic leukemia. When myeloid cells are affected, the disease is called myelogenous leukemia. The disease can be categorized into one of four main types shown below, depending on whether it is acute or chronic and myelogenous or lymphocytic.

While both children and adults can develop leukemia, certain types are more common in one age group than in another. However, Keller was diagnosed with acute lymphocytic leukemia (ALL), which is most prevalent among children, at age 31. Although he died less than a year later, Kathy Keller says that at the time the prognosis for people with ALL seemed good. "They said it was critical, sure — that Neil's condition was life-threatening," she remembers, "but we got lucky that the attending physician turned out to be someone who recognized the urgency in getting Neil immediate medical attention."

In addition to the four main types, there are sub-types of leukemia, such as acute promyelocytic leukemia (APL), and hairy cell — a chronic leukemia in which the abnormal white blood cells appear to be covered with tiny hairs when viewed under a microscope.

Symptoms

Some people with leukemia may not experience any symptoms at all and their first inkling of a problem could be the results of a routine blood test. Others, however, may complain of flu-like symptoms such as fatigue, fever, weight loss, and night sweats. Other signs of leukemia can include:

• easy bruising or bleeding
• lymph node enlargement
• bone pain
• swelling of the abdomen due to an enlarged liver and spleen
• increased susceptibility to infection

Diagnosis

Common blood tests, such as the complete blood cell count (CBC), as well as blood cell examination under a microscope, can provide the first evidence that a person has leukemia. Most people with acute leukemia, like Keller, will have an increased number of white blood cells, not enough red blood cells, and not enough platelets.

"Neil's white blood counts were as high as his doctor had ever seen," says Kathy Keller. "But he also indicated that Neil's type of leukemia had a 90 percent cure rate with a two-year treatment plan."

In addition to the CBC, a bone marrow test is frequently performed to confirm the diagnosis and determine the type of leukemia. Bone marrow is the soft, spongy tissue in the center of the bones that produces the white blood cells, red blood cells and platelets. Two kinds of tissue samples are taken for examination under a microscope and for special tests such as chromosomal analysis. In a procedure known as a bone marrow "aspiration," cells are withdrawn with a fine needle and syringe. A bone marrow "biopsy" involves taking a piece of bone with marrow inside, using a larger needle. Both samples usually are taken from the same site, generally on the back of the pelvic bone.

Other diagnostic tests could include:

• removing and testing an entire lymph node
• drawing fluid from the spinal cavity in the lower back (spinal tap)
• measuring certain chemicals in the blood (to determine liver or kidney problems caused by leukemia or certain chemotherapy drugs)
• using X-rays, computed tomography (CT) scans, magnetic resonance imaging (MRI), or ultrasound imaging, to obtain detailed images of internal organs.

About the Author

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