It is most likely to affect people over the age of 55 years, but it is also the most common cancer in those aged under 15 years.
In the United States, 62,130 people are expected to receive a diagnosis of leukemia in 2017, and around 24,500 deaths will likely be due to this disease.
Acute leukemia develops quickly and worsens rapidly, but chronic leukemia gets worse over time.
Here are some key points about leukemia. More detail is in the main article.
- About 62,130 new cases of leukemia are expected to be diagnosed in the United States in 2017.
- Leukemia is one of the most common childhood cancers, but it most often occurs in older adults.
- Leukemia can be fatal, but there are ways of treating and controlling the disease and its symptoms.
Leukemia happens when the DNA of immature blood cells, mainly white cells, becomes damaged in some way.
This causes the blood cells to grow and divide continuously, so that there are too many.
Healthy blood cells die after a while and are replaced by new cells, which are produced in the bone marrow.
The abnormal blood cells do not die when they should. They accumulate, occupying more space.
As more cancer cells are produced, they stop the healthy white blood cells from growing and functioning normally, by crowding out space in the blood.
Essentially, the bad cells crowd out the good cells in the blood.
Some factors increase the risk of developing leukemia.
The following are either known or suspected factors:
- artificial ionizing radiation
- viruses, such as the human T-lymphotropic virus (HTLV-1) and HIV
- benzene and some petrochemicals
- alkylating chemotherapy agents used in previous cancers
- hair dyes
Genetic predisposition: Some people appear to have a higher risk of developing leukemia because of a fault in one or several genes.
Down syndrome: People with Down syndrome appear to have a higher risk, possibly due to certain chromosomal changes.
It has been suggested that exposure to electromagnetic energy might be linked to leukemia, but there is not enough evidence to confirm this.
There are various types of leukemia, and they affect people differently. Treatment options will depend on the type of leukemia and the person's age and overall state of health.
Progress in medicine means that treatment can now aim for complete remission, where the cancer goes away completely for at least 5 years after treatment.
In 1975, the chances of surviving for 5 years or more after receiving a diagnosis of leukemia were 33.1 percent. By 2009, this figure had risen to 62.9 percent.
The main type of treatment is chemotherapy. This will be tailored to the type of cancer a patient has.
If treatment starts early, the chance of remission is higher.
Types of treatment include:
Chemotherapy can affect the whole body, but targeted therapy is aimed at a specific part of the cancer cell.
Some types of chronic leukemia do not need treatment in the early stages, but monitoring is essential. The oncologist may suggest watchful waiting with frequent doctor's visits.
For a type of leukemia known as chronic myeloid leukemia (CML), a bone marrow transplant may be effective. Younger patients are more likely to undergo transplantation successfully.
Signs and symptoms of leukemia vary.
They may include:
- being tired all the time
- weight loss
- having fevers or chills
- getting frequent infections
There is more information on symptoms later in this article.
Leukemia can be divided into four main groups. These groups distinguish acute, chronic, lymphocytic, and myelogenous leukemia.
Chronic and acute leukemia
During its lifespan, a white blood cell goes through several stages.
In acute leukemia immature, useless cells develop rapidly and collect in the marrow and blood. They are squeezed out of the bone marrow too early and are not functional.
Chronic leukemia progresses more slowly. It allows more mature, useful cells to be made.
In other words, acute leukemia crowds out the good cells more quickly than chronic leukemia.
Lymphocytic and myelogenous leukemia
Leukemias are also classified according to the type of blood cell they affect.
Lymphocytic leukemia occurs if the cancerous changes affect the type of bone marrow that makes lymphocytes. A lymphocyte is a kind of white blood cell that plays a role in the immune system.
Myelogenous leukemia happens when the changes affect the type of marrow cells that go on to produce red blood cells, other types of white cells, and platelets.
Acute lymphocytic leukemia (ALL)
Also known as acute lymphoblastic leukemia, this is the most common type of leukemia among young children. It can also affect adults, especially after the age of 65 years. Among children, the 5-year survival rate is higher than 85 percent.
The subtypes of ALL are:
- precursor B acute lymphoblastic leukemia
- precursor T acute lymphoblastic leukemia
- Burkitt's leukemia
- acute biphenotypic leukemia
Chronic lymphocytic leukemia (CLL)
This is most common among adults over 55 years, but younger adults can also have it. It is the most common type of leukemia in adults, and it rarely affects children. It is more common in men than in women.
A person with CLL has an 82 percent of surviving 5 years after diagnosis.
Acute myelogenous leukemia (AML)
AML is more common in adults than in children. It affects men more often than women.
It develops quickly, and symptoms include fever, difficulty breathing, and pain in the joints. Environmental factors can trigger it.
Chemotherapy is the main treatment. Sometimes, a bone marrow transplant may be recommended.
Chronic myelogenous leukemia (CML)
CML mostly affects adults. According to the National Cancer Institute, the 5-year survival rate is 65.1 percent.
However, many people with CML have a gene mutation that responds to targeted cancer therapy, called Gleevec, or imatinib. For those people whose cancer is susceptible to Gleevec, the 5-year survival rate can be up to 90 percent.
Signs and symptoms of leukemia include the following:
Poor blood clotting: Immature white blood cells crowd out platelets, which are crucial for blood clotting. This can cause a person to bruise or bleed easily and heal slowly. They may also develop petechiae, small red to purple spots on the body, indicating a minor hemorrhage.
Frequent infections: The white blood cells are crucial for fighting off infection. If these are suppressed or not working properly, frequent infections can result. The immune system may attack other good body cells.
Anemia: As the shortage of good red blood cells grows, anemia can result. This can involve difficult or labored breathing and pale skin.
Other symptoms: There may be nausea, fever, chills, night sweats, flu-like symptoms, weight loss, bone pain, and tiredness. If the liver or spleen becomes enlarged the person may feel full and will eat less, resulting in weight loss.
Weight loss can also occur even without an enlarged liver or spleen. Headache may indicate that the cancerous cells have invaded the central nervous system (CNS).
These can all be symptoms of other illnesses. Tests are needed to confirm a diagnosis of leukemia.
A doctor will carry out a physical examination and ask about personal and family medical history. They will check for signs of anemia and feel for an enlarged liver or spleen.
They will also take a blood sample for assessment in the laboratory.
If the doctor suspects leukemia, they may suggest a bone marrow test. Bone marrow is taken, usually from the hip, using a long, fine needle. This can help to show which kind of leukemia, if any, is present.
The outlook for people with leukemia depends on the type.
All patients who experience remission will need to undergo regular monitoring, including blood tests and possible bone marrow tests, to ensure the cancer has not returned.
If the leukemia does not return, the doctor may decide, over time, to reduce the frequency of the tests.
Leukemia strikes all ages and both sexes. In 1995 approximately 20,400 people died from Leukemia. The all time five year survival rate is 38%. This rate has gone to 52% in the mid 1980’s. Approximately 25,700 cases were reported in 1995 alone(American Cancer Society-leukemia, 1995).
Leukemia is a form of cancer in the blood cells. Most forms of Leukemia occur in the white blood cells. These abnormal cells reproduce in large quantities and look and perform differently than normal cells(MedicineNet-leukemia, 1997).
Right now the causes of Leukemia are unknown. Some studies have shown that exposure to high-energy radiation increases chances of contracting leukemia. Such radiation was produced in the atomic bombing of Japan during World War II. There is also enough energy in nuclear plants so strict safety precautions are taken. Some research shows that exposure to electric magnetic fields, such as power lines and electric appliances, is a possible risk factor. More studies are needed to prove this link. Some genetic conditions, such as Down’s syndrome, are also believed to increase the risk factor. Exposure to some chemicals is also suspected to be a risk factor. By learning the causes of leukemia treatment options will become available(MedicineNet-leukemia, 1997).
There are many symptoms of leukemia. The symptoms of leukemia are the same for all the different types of leukemia. The acute types of leukemia, ALL and AML, symptoms are seen more quickly than in the chronic types of leukemia, CLL and CML, where symptoms do not necessarily appear right away. The symptoms are flu symptom, weakness, fatigue, constant infections, easily bleed and bruise, loss of weight and appetite, swollen lymph nodes, liver or spleen, paleness, bone or joint pain, excess sweating, swollen or bleeding gums, nosebleeds and other hemorrhages, and red spots called petechiae located underneath the skin. In acute Leukemia the cancerous cells may collect around the central nervous system. The results can include headaches, vomiting, confusion, loss of muscle control, or seizures. These clumps of cancer cells can collect in other various parts of the body(MedicineNet-leukemia, 1997 and American Cancer Society-leukemia, 1995).
Leukemia can be diagnosed in a number of ways. Blood work is commonly done in the laboratory. Different forms of blood work include checking the hemoglobin count, platelet count, or white blood cell count. X-rays are routinely done for treatment follow-up. Ultrasound is also used as a treatment follow-up. CT Scan is a special type of x-ray used as a detailed cross section of a specific area of the body. Bone marrow is routinely tested to examine progress of the disease. Spinal taps are also used in certain types of cancers. The spinal fluid is checked to see if cancer cells are present(Parent and Patient handbook-hematology/oncology clinic, Children’s Hospital of Michigan, 19??)
Treatment of Leukemia is very complex. Treatments are tailored to fit each patient’s needs. The treatment depends on the type of the cancer and features of the cells. It also depends on the patient’s age, symptoms, and general health. Acute Leukemia must be treated immediately. The goal of treatment is to get the cancer into remission. Many people with Leukemia may be cured. To be considered cured, you must be cancer free for at least five years. This time also varies depending on the type of cancer. The most common treatment of Leukemia is chemotherapy. Bone marrow transplants, Radiation, or biological therapy are also available options. Surgery is also occasionally used. Chemotherapy is a treatment method in which drugs are given to kill off the cancerous cells. One or more drugs may be used depending on the type of Leukemia. Anticancer drugs are usually given by IV injection. Occasionally they are given orally. Chemotherapy is given in cycles: a treatment period followed by a recovery period followed by another treatment period and this process continues for a certain amount of time. Radiation therapy is used along with chemotherapy in some occasions. Radiation uses high energy beams to kill the cancerous cells. Radiation can be applied to either one area or to the whole body. It is applied to the whole body before bone marrow transplants. Bone marrow transplants are used in certain patients. The patients bone marrow is killed by high doses of drugs and radiation. The bone marrow is then replaced by a donor’s marrow or the patient’s marrow that was remove before the high amounts of drugs and radiation. Biological therapy involves substances that affect the immune system’s response to the cancer(MedicineNet-leukemia, 1997).
In conclusion, Leukemia can be fatal, but with early diagnosis, proper treatments, and a lot of luck, it can be put into remission. With treatment options improving constantly, there may one day be a sure cure. Leukemia is a very dominant disease and very hard to treat. The key may be in the causes.
Filed Under: Cancer, Medicine, Science & Technology