Leukemia.com defines the disease as, “a malignant disease of the bone marrow and blood, characterized by the uncontrollable accumulation of blood cells.” Often mischaracterized as a childhood disease, leukemia actually affects about 10 times more adults than children. It is more common in men than women and found in more Caucasians than African Americans.
By Julianne Hale
Dr. Manoo Bhakta, pediatric hematologist and oncologist at Erlanger’s T.C. Thompson Children’s Hospital, explains Leukemia as a disease that begins in the bone marrow with white blood cells that begin to divide out of control. The white blood cells, which normally fight infection, no longer function correctly.
Dr. Derek Holland, hematologist and oncologist with Chattanooga Oncology & Hematology Associates, notes, “If untreated, they can crowd out and prevent production of the normal blood cells.”
Causes
It is not possible to pinpoint the specific cause of leukemia. While the presence of some chromosome abnormalities has a strong correlation to certain types of leukemia, there are also a wide variety of environmental factors to consider including smoking, prolonged exposure to radiation and the presence of certain chemicals in the home or workplace.
Signs and Symptoms
“To understand the symptoms of leukemia, you just need to look at what happens in the body,” explains Dr. Holland. “The bone marrow produces white blood cells that fight infection, red blood cells that circulate oxygen and platelets that help clot. When you have a malignant cell that is dividing out of control, it squeezes out production of these normal cells. The lack of production of normal white blood cells causes the patient to experience infection, which can cause a fever and chills. Reduced production of red blood cells can cause shortness of breath and anemia, and lower numbers of platelets can cause bruising and bleeding in the gums.”
“Patients often have several non-specific symptoms,” says Ashley Tanis, Health Initiatives representative for the American Cancer Society in Chattanooga. “They can include weight loss, fever, night sweats, fatigue and a loss of appetite.” However, Tanis cautions against immediately attributing them to leukemia. She says, “Of course, these are not just symptoms of leukemia and are often caused by something else. If anyone has a concern about a possible symptom, they should report it to their physician.” Other symptoms include swelling in the abdomen, enlarged lymph nodes and bone and joint pain.
Types of Leukemia
Leukemia is categorized into four types based on the cells involved (myelogenous or lymphocytic) and the rate of progression (acute or chronic). Acute leukemia gets worse quickly and may cause symptoms immediately, while chronic leukemia gets worse slowly and may not cause symptoms for years. Myelogenous leukemia affects white blood cells called myelocytes, and lymphocytic (or lymphoblastic) leukemia affects white blood cells called lymphocytes.
1. Acute Lymphocytic Leukemia (ALL) is a rapidly progressing cancer that involves white blood cells (lymphocytes) in the bone marrow. ALL accounts for three out of four cases of childhood leukemia but can also be present in adults.
2. Chronic Lymphocytic Leukemia (CLL) is a slower progressing cancer that also starts in the lymphocytes but is more common in the older population. CLL almost never affects children.
3. Acute Myelogenous Leukemia (AML) is a rapidly progressing cancer that begins in the blood-forming cells of the bone marrow. AML occurs in both adults and children.
4. Chronic Myelogenous Leukemia (CML) is a less common, slower progressing type of cancer that begins in the blood-forming cells of the bone marrow. Rarely seen in children, CML usually affects older adults.
Childhood Leukemia
Leukemia accounts for 33 percent of cancers in children ages 0-14, explaining why many associate the disease with children. Ashley Tanis notes, “Almost all childhood leukemia is acute. The disease still originates and behaves the same way it would in an adult. Although there are exceptions, childhood leukemia tends to respond better to chemotherapy. Children also tolerate chemotherapy better than adults. But, because chemotherapy can have long-term side effects, children need careful attention for the rest of their lives.”
Leukemia in Adults
With a median age of diagnosis at 66 years old, leukemia is more likely to strike older adults than any other population. The two most common types of leukemia among adults are AML and CLL.
The prognosis for adults with AML is not as good as for children. One significant difference between the treatments of adults versus children with AML is the stem cell transplant procedure. Often leading to a complete recovery in younger patients, the procedure is often too risky for patients over the age of 45.
For adults with CLL, the prognosis is quite good. The treatment for CLL tends to be conservative, and patients can live for many years with this disease.
Treatment
“All types of leukemia are typically treated with chemotherapy, but the type of chemotherapy is very different dependant on the type of leukemia that a patient has,” explains Dr. Holland.
The acute forms of the disease (AML and ALL), are treated with inpatient chemotherapy in the hospital. This treatment, which typically lasts about a month, is called induction chemotherapy. Once the patient reaches remission, consolidation chemotherapy is done to keep them there.
The treatment for chronic types of leukemia (CML and CLL) is usually performed in an outpatient setting. Dr. Holland explains, “The treatment for CML has been revolutionized in the past ten years with the advent of the drug Gleevec. This is a therapy that targets the precise genetic abnormality in CML. While Gleevec is not a cure, it does put patients in remission and keeps them there for years.”
Leukemia patients are sometimes given the option of a bone marrow transplant, a risky procedure that can cure the disease completely. During the operation, the patient’s bone marrow is destroyed by intensive chemotherapy to avoid rejection of new marrow. After the patient’s diseased bone marrow has been destroyed by chemotherapy, the patient is given marrow from a healthy donor to reconstitute the marrow. This can be quite dangerous because patients have almost no white blood cells and cannot fight infection, but once the patient’s body has time to multiply the donor marrow, the ability to fight infection increases, and the chance for long-term remission and a complete cure improves.
In dire circumstance which are becoming increasingly rare for children, this procedure is a last effort to make sure the cancer will not recurr. Dr. Bhakta notes that before, when treatments were less precise, the cancer would often come back, leaving bone marrow transplant as the only option. Today, through risk assessment, doctors are able to more effectively treat children, making a bone morrow transplant much less common.
Improved Outcomes
“In the year 2010, it’s such a good feeling to be able to sit down with a family and say, ‘I think we can cure this thing,’” says Bhakta. Thanks to medical advancements, the prognosis for leukemia has improved dramatically in the past 50 years. Some of the most impressive strides have been within the realm of ALL in childhood leukemia. In the 1960s, children diagnosed with ALL were not expected to survive. In 1981, the survival rate rose to 30 percent, and today the survival rate is between 90-95 percent, according to Dr. Bhakta. Leukemia is increasingly becoming a disease that people can live with and, in many cases, completely recover from.
Treatment Options in Chattanooga
With top-notch medical care and professionals here in the Tennessee Valley, leukemia patients in the Chattanooga area can stay close to home for most of their medical care. Discussing the treatment options available in the Scenic City, Dr. Holland says, “For AML, CML and CLL all therepies can be done here in Chattanooga, except some clinical trials.” Dr. Bhakta notes that for ALL, 95 percent of treatment can be given in Chattanooga. The only reason to go anywhere else is for a bone marrow transplant. T.C. Thompson Children’s Hospital is part of the Children’s Oncology Group, a national and internation network that guarantees the most up-to-date and effective treatment possible.
While there is no doubt that leukemia can be a devastating disease, Dr. Holland is hopeful about the future. He says, “I’d like to encourage people to think of leukemia as a serious disease but not as a death sentence. I think there are some very exciting changes around the corner. It is my hope and belief that we are going to see some positive changes in the next three to five years.”
Julianne Hale and her family reside in Cleveland. She earned a Bachelor of Science degree from Illinois State University and then an MBA from the University of Phoenix. Julianne is a member of the Chattanooga Writers Guild, is married and has three children.