What is Leukemia?
Leukemia is a cancer occurring in a bone’s marrow cells. Though images of skeletons give us the impression that our bones are solid, the rigid exterior actually houses a spongy middle called the marrow. When functioning normally, marrow cells produce the three different types of blood cells (red, white, and platelets) your body needs to carry nutrients to its organs, attack germs, and heal wounds. In leukemia patients, these marrow cells overproduce, flooding the blood with defective cells.
Types of Leukemia
Leukemia is typed by two designations. The first designation describes how mature the cells being overproduced are. If these cancer cells are immature cells (called “blasts”), the leukemia is labeled “acute.” If these cancerous blood cells are matured but abnormally formed, the leukemia is labeled “chronic.”
The second designation describes if the diseased cells are lymphoid cells (white blood cells circulating in the blood) or myeloid (white blood cells remaining in the bone marrow).
These two designations define the following four types of leukemia:
- Acute lymphocytic leukemia (ALL)
- Acute myelogenous leukemia (AML)
- Chronic lymphocytic leukemia (CLL)
- Chronic myelogenous leukemia (CML)
Causes of Leukemia
Medical science does not attribute a single cause for leukemia. Rather, doctors studying this cancer suggest the following agents as “risk factors.”
Smoking. Cigarettes contain certain carcinogenic (cancer-causing) compounds, such as benzene, polonium-210 (a radioactive poison found in tobacco plants), and polycyclic aromatic hydrocarbons (a group of about 10,000 compounds found in burning carbon). These substances have shown an increase risk of leukemia (25% of persons with acute myelogenous leukemia were/are cigarette smokers).
Radiation. Leukemia occurs more frequently in those who are exposed to high levels of radiation, such as nuclear power plant and nuclear arms workers. Leukemia was the cause of death for many Hiroshima and Nagasaki residents not killed in the immediate World War II atomic blasts.
Toxic chemicals. Industrial workers exposed to the cancer-causing chemicals of benzene and formaldehyde show a higher incidence of leukemia. Additionally, some cancer patients treated by chemotherapy develop leukemia later in life, a risk that is increased if the patient also undergoes radiation therapy, according to the American Cancer Society (click here to read).
Leukemia is treated by attacking the cancer cells. The two traditional leukemia treatments are radiation and chemotherapy. “Chemotherapy” is named for the cocktail of chemicals used to kill rapidly dividing cells. Because cancer cells reproduce more quickly than normal cells, cancer cells take the most damage from chemotherapy.
After cancer cells are killed off, recovering leukemia patients receive injections of donated stem cells. These stem cells act just like their sister cells already in the blood marrow. The donor’s stem cells can come from painful bone marrow extractions, from umbilical cord material, or from peripheral blood stem cells filtered from a healthy donor blood.
The newest form of leukemia treatments is quickly making radiation, chemotherapy, and stem cell transplants a thing of the past—and it comes in an easy-to-swallow pill.
Called “targeted therapy,” this pill uses specific chemicals to shut down the enzymes that cause the cancer cells to reproduce. Imatinib (brand name Gleevec®) is the first drug of this kind. Approved in 2001, imatinib has been highly effective in targeting tyrosine kinase, the enzyme that causes chronic myelogenous leukemia (CML) cells to overproduce and has become the treatment of choice for CML.
Future of Leukemia Treatments
Future treatments for leukemia will come from genetics. Specifically, there will be further increases in targeted therapy’s magic pills and in the use of genetically modified bacteria to attack leukemia cells.
Targeted therapy to treat leukemia continues to expand with two new drugs (nilotinib and dasatinib) in phase iii clinical trials for that minority of patients whose chronic myelogenous leukemia (CML) resists imatinib. Almost all cases of CML and a minority of acute lymphocytic leukemia cases (known as Ph-positive ALL) are the result of a mutated chromosome in the bone marrow called the Philadelphia (Ph) chromosome. Results published in the New England Journal of Medicine and summarized here by the National Cancer Institute show that nilotinib and dasatinib are highly affective in targeting this dangerous chromosome.
Genetically modified bacteria also holds promise of safer, more effective leukemia treatments. Modifying bacteria to deliver toxins directly to a tumor has been shown effective in phase i clinical trials for two immunotoxins labeled LMB-2 and BL22. These immunotoxins were shown highly effective in treating hairy cell leukemia, an uncommon type of chronic lymphoid leukemia (CLL). Click to read more about how these immunotoxins are created or click here if you want to learn more about the trial results.
Additionally, many clinics are now offering a combination of Western and alternative medicine treatments to leukemia patients. The aim of these projects is to treat both the cancer as well as the whole person.
New medical findings and leukemia research has lead to new methods of treatment. To learn how you can help, see our clinical trial section.
Lawyers for Change
If you suspect you or your loved one's leukemia was caused by benzene exposure, please contact The Consumer Justice Group. Our network of benzene attorneys across the country can begin an investigation of a workplace for possible benzene exposure.
The Leukemia Health News is a service of the Consumer Justice Group.