Leukemia is a broad medical term for cancer of the blood. This includes blood, bone marrow, and the lymphatic system. Like all cancers, this is a disease process that arises from uncontrolled division of abnormal cells in the blood and the bone marrow, and carrying the risk of spreading to other organs and systems in the body. Leukemia may refer to any of the various types of blood cancer, including those prevalent primarily in children or in adults.
Types
There are four main types of blood cancer or leukemia. These are often referred to by their abbreviated form. The four types are acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL), acute myelogenous leukemia (AML) and chronic myelogenous leukemia (CML), The two basic principles behind the categorization of these types of leukemia are those of how quickly it develops and worsens and the type of white blood cells it affects. The different types of leukemia also have varying incidences among adults and children, with chronic lymphocytic leukemia and acute myelogenous leukemia being more common in adults. Acute leukemia presents with anomalies of immature cells (or blastocytes), resulting in rapid development of blood related complications. Acute leukemia requires immediate and aggressive intervention. Chronic leukemia present with anomalies of mature cells, and they tend to replicate slowly and no blood related dysfunction may be apparent for a long period of time. In children, the more common form of leukemia that is seen is acute lymphocytic leukemia.
Causes
Leukemia has no single known cause. It manifests as an abnormal mutation of the DNA of blood cells, in which the growth and decay signals are altered. So the cells divide and grow more rapidly, and do not start decaying and dying when they are supposed to. As a result, there is a proliferation of abnormal cells. Scientists have, however, been able to come to the conclusion that the incidence of leukemia is linked to a combination of genetic and environmental factors.
The two common environmental factors believed to contribute to the incidence of leukemia are exposure to radiation and to carcinogenic substances. Several chemotherapeutic agents that are used to treat other forms of malignancies have been found to cause leukemia. Certain less common forms of leukemia, such as Adult T-Cell leukemia has been found to be virally mediated.
Family history of leukemia has been definitively linked with higher risk of developing the disease. Interestingly, the same type of leukemia tends to appear in patients with family history of leukemia.
Symptoms
Patients with acute leukemia display symptoms early on in the disease. In cases of chronic leukemia, the patient may actually be symptom-free for years after the onset of the disease. The common symptoms of leukemia include fever or chills, fatigue and weakness with no apparent explanation, recurring infections, unexplained weight loss, swollen lymph nodes, enlargement of the liver and spleen, easy bruising, easy bleeding, the appearance of tiny red petechial spots on the skin, excessive nighttime sweating and bone pain and tenderness. These symptoms are largely generalized, and it may be commonly confused with other conditions such as viral infection or influenza.
Diagnosis
Due to the generalized nature of the symptoms of this disease, a lot of cases do not get correctly diagnosed till it is too late. This is why it is essential to be familiar with one’s risk profile for leukemia. The common physical manifestations of this disease that can be detected on a physical exam are paleness from anemia, and swelling of organs like the liver or spleen. The two definitive diagnostic tools are repeated complete blood counts, and biopsy of bone marrow aspirate. If complete blood counts repeatedly show abnormally elevated white blood cells or platelet counts and/or suppression of other counts, and if there are concurrent physical symptoms of leukemia, the physician will likely recommend a bone marrow biopsy. The biopsy can also determine the type of leukemia that the patient is afflicted with.
Treatment
Options and decisions for treatment of leukemia are influenced by several factors, such as type of leukemia, age, overall health, stage and grade at which the disease is, and whether it has spread to other parts of the body or not. At the present time, a wide variety of treatment options are used by physicians. Chemotherapy is the most commonly used treatment for patients with leukemia. This form of therapy uses chemicals which can destroy the cancerous cells. These may be taken in pill form or injected into the body. Typically a combination of different chemical may be used in the case of leukemia, which is referred to as combination chemotherapy. Radiation therapy uses focused high energy radiation to irradiate or destroy the cancerous cells. Radiation therapy may be offered in combination with chemotherapy.
Bone marrow transplantation is another treatment option that the physician may consider. Also known as stem cell transplantation, this therapy replaces your damaged bone marrow with healthy bone marrow cells or with stem cells. The damaged cells are first destroyed by using chemotherapy or radiation (or a combination of both), and then bone marrow stem cells are infused, either autologously using the patients own stem cells or from a genetically matching donor.
Decision making regarding treatment options and whether or not to treat the condition is largely determined by the perceived outcome of such initiatives. If the physician is not convinced that the benefits of treatment outweigh the risks, he may choose a management option accordingly. In some cases, the physician may choose to treat secondary cancers in order to preserve the health of the patient. These are complex issues that are dictated by several variables.
Prevention
There is no known way to predict or prevent leukemia. The best one can do is ensure early detection and start immediate treatment intervention. The only way to prevent this disease from reaching a stage where it cannot be treated is by education and awareness. Being aware of the risk factors and one’s personal risk profile for leukemia can help identify the symptoms of the disease early on. Educating people about the presence of carcinogens in the environment can prevent the spread of this disease. Avoiding exposure to environmental radiation, and exposure to carcinogenic substance will also help prevent this disease.
