Leukemia is a frightening diagnosis, and until the last few decades it was a disease with few good treatment options. But advances in chemotherapy and other types of treatment have markedly improved the likelihood of achieving remission and long-term survival. Leukemia includes a broad group of different cancers of the blood and bone marrow, each with its own natural history, treatment and remission rates. The common goal of all treatment is control and destruction of the malignant cells, hopefully allowing a long and healthy life after therapy. Explaining remission in leukemia requires some understanding of the disease, its treatment and what to expect after therapy is completed.
Leukemia is Cancer
Step 1
Leukemia usually starts in the bone marrow from immature cells that normally produce the cells in your blood. One of these cells undergoes a genetic mutation, allowing it to divide and proliferate in an uncontrolled fashion, with all the resulting new cells sharing the same genetic change. Although some leukemias have been linked to chemical exposure, radiation or underlying genetic disorders, the exact cause of most leukemias remains unknown.
Step 2
Different types of leukemia arise most commonly from immature white cells or lymphocytes, but they can originate from immature red blood cells or platelet-forming cells also. Leukemias are classified as either acute, indicating the malignant cells are more immature and spreading rapidly, or chronic, if the cells are more mature in appearance and the disease progresses more slowly. Examples include the common childhood form of acute lymphocytic leukemia and adult chronic myelogenous leukemia.
Step 3
Rather than forming a lump or mass like most cancers, an expanding population of leukemia cells fills the bone marrow and eventually spills out into the circulating blood. Not only do the leukemia cells not function normally, but as they overwhelm the bone marrow, they also replace the normal blood-forming cells. This leads to the common symptoms of bleeding, anemia and lowered ability to fight infections seen in most types of leukemia.
Diagnosis and Treatment of Leukemia
Step 1
Leukemia is diagnosed when malignant cells are discovered in the bloodstream, bone marrow or lymph nodes. Complete blood counts, bone marrow biopsy and radiology scans are usually performed, along with cytogenetic studies to look for any chromosomal abnormalities and help determine the cell type of the leukemia. This information plays an important role in determining treatment options and the overall prognosis.
Step 2
Specific treatment for leukemia depends on the type of leukemia and its stage, or how extensive the disease has become. Some chronic leukemias, such as chronic lymphocytic leukemia, may not require any treatment until blood cell counts become very high or the patient develops symptoms. Most acute leukemias require immediate treatment with aggressive chemotherapy, sometimes along with radiation therapy, bone marrow transplant or other options.
Step 3
Chemotherapy involves using one or more drugs that enter the bloodstream to damage the leukemia cells, most often by interfering with their ability to divide and multiply. Depending on the type of leukemia being treated, chemotherapy can be expected to kill some or nearly all of the malignant cells, with different drugs more effective for some types than others. The ultimate goal of leukemia treatment is to achieve a complete remission -- the disappearance of all detectable malignant cells.
The Meaning of Remission
Step 1
How a leukemia responds to treatment needs to be assessed both during and after completion of therapy. A complete remission means the oncologist, or cancer specialist, can find no evidence of any leukemia by physical examination, laboratory tests, radiologic scans or other studies. Blood counts return to normal and anemia, bleeding and other symptoms resolve. A partial remission means some shrinkage or slowing of the leukemia is seen, but leukemia cells are still present.
Step 2
Even when no evidence of leukemia can be found in complete remission, there may be rare undetectable malignant cells remaining. Over the following weeks, months or years these may eventually grow in number and result in a recurrence of leukemia. Therefore, after all treatments are finished, the oncologist will set up a plan of regular follow-up visits to check for recurrent leukemia or complications of treatment. If a recurrence is detected, additional chemotherapy or alternative treatments can be tried to achieve another remission.
Step 3
Because leukemia can still relapse long after a complete remission, doctors do not usually use the word “cure” when talking about cancer treatments. The longer a complete remission lasts, the better chance a patient has of long-term survival without future recurrence of disease. According to The Leukemia and Lymphoma Society, five-year survival for all types of leukemia combined reached 55 per cent in 2006, with survival in young children treated for acute lymphocytic leukemia as high as 91 per cent.
Tips and Warnings
- Discussing leukemia, its treatment and the meaning of remission can be an emotional and difficult undertaking. A doctor who works with leukemia patients, your local cancer center or hospital should be able to help you obtain more specific information or direct you to local agencies that can be of assistance.
