What is Leukemia?   
 
Leukemia is a type of cancer that starts in the soft, inner part of the bones (bone marrow) and often moves quickly into the blood. It can then spread to other parts of the body such as the:

• Lymph nodes
• Spleen
• Liver
• Central nervous system
• Other organs

In contrast, other types of cancer can start in these organs and then spread to the bone marrow (or elsewhere). Those cancers are not leukemia. Both children and adults can get leukemia.

Normal Bone Marrow and Lymphoid Tissue

In order to understand the different types of leukemia, it helps to have some basic knowledge of the blood and lymph systems.

Bone marrow is the soft, spongy, inner part of bones. All of the different types of blood cells are made in the bone marrow. Bone marrow is made up of:

• Blood-forming cells
• Fat cells
• Tissues that aid the growth of blood cells.

Early blood cells are called blood-forming stem cells. These stem cells grow in an orderly process to produce red blood cells, white blood cells, and platelets. (They are different from embryonic stem cells which are formed from a developing fetus and can develop into other kinds of cells in the body.)

Red blood cells carry oxygen from the lungs to all other tissues of the body. They also carry away carbon dioxide, a waste product of cell activity. A shortage of red blood cells causes weakness, shortness of breath, and tiredness.

Platelets are actually pieces that break off from certain bone marrow cells. They are called platelets because they look a little bit like plates when seen under the microscope. Platelets help stop bleeding by plugging up areas of blood vessels damaged by cuts or bruises.

White blood cells help defend the body against germs – viruses and bacteria. There are quite a few types of white blood cells. Each has a special role to play in protecting the body against infection. The 3 main types of white blood cells are granulocytes, monocytes, and lymphocytes. The suffix-cyte means cell.

The immune system is made up mainly of lymphoid tissue (also known as lymphatic tissue). Lymphoid tissue is found in many places throughout the body, including the:

B Lymphocytes

T lymphocytes

• Lymph nodes
• Thymus
• Spleen
• Tonsils and adenoids
• Bone marrow

The Lymphatic System Consists of:

• Lymph vessels - like veins except that they carry a clear fluid (lymph) instead of blood
• Lymph nodes
• Lymph fluid - contains excess fluid from tissues, waste products, and immune system cells

The main cell type that forms lymphoid tissue is the lymphocyte. The two main types of lymphocytes are called:

• B-cells 
• T-cells

Normal T-cells and B-cells do different jobs within the immune system. Any of the blood-forming or lymphoid cells can turn into a leukemia cell. Once that happens, the cell can reproduce to form many new cancer cells. Eventually, these cells can overwhelm the bone marrow, spill out into the bloodstream, and spread to other organs. Acute lymphocytic leukemia starts from early forms of the lymphocytes.

The Different Types of Leukemia

There are four major types of leukemia:

• Acute 
• Chronic
• Lymphocytic
• Myeloid

In acute leukemia, the bone marrow cells don’t mature properly. These immature cells continue to reproduce and crowd out normal cells. Some types of acute leukemia respond well to treatment and many patients are cured. Other types have a less favorable outlook.

In chronic leukemia the cells look mature, but they are not really normal and they can’t fight infection they way they should. Also, the cells live too long, build up, and crowd out normal bone marrow cells.

Lymphocytic and myeloid (or myelogenous) refer to the different cell types from which leukemias start. Lymphocytic leukemias develop from lymphocytes in the bone marrow. Myeloid leukemia mainly develops from other types of white blood cells such as granulocytes or monocytes.

Most cases of leukemia can be sorted into one of the four main types:

• Acute lymphocytic leukemia (ALL)
• Acute myeloid leukemia (AML)
• Chronic lymphocytic leukemia (CLL)
• Chronic myeloid leukemia (CML)    

Acute Lymphocytic Leukemia (ALL) is a type of cancer that starts from these white blood cells in the bone marrow.

• "Acute" means that the cancer develops quickly, and if not treated, could be fatal in a few months
• "Lymphocytic" (limf-o-sit-ik) means that the cancer starts from cells called lymphocytes 

How Many People Get Acute Lymphocytic Leukemia?

In 2008 there will be about 44,270 new cases of all types of leukemia in the United States. Of these, about 5,430 will be acute lymphocytic leukemia (ALL). Although this is mainly a disease of children, about 1,300 cases will be in adults. About 1,460 people will die of ALL in the United States in 2006. About three of out four of them will be adults.

The risk of ALL is lowest between the ages of 25 and 50 and then begins to pick up. African Americans are much less likely to have ALL.

What Causes Acute Lymphocytic Leukemia?
 
The cause of most cases of ALL remains unknown at this time. But some cases can be linked to certain risk factors. At this time, there are no known lifestyle risk factors for ALL.

Risk Factors for ALL:

• Being a survivor of an atomic bomb blast or nuclear reactor accident has been linked to ALL.
• There is some concern about very high-voltage power lines as a risk factor for leukemia. The United States National Cancer Institute (NCI) has several large studies going on now to look into this question. So far, the studies show either no increased risk or a very slightly increased risk. Clearly, most cases of leukemia are not related to power lines.
• A small number of people are at greater risk of acute leukemia because they have certain rare diseases or because the have a certain virus (HTLV-1).

Can Acute Lymphocytic Leukemia be Prevented?

Most people who develop ALL do not have any of the above risk factors. The cause of their leukemia remains unknown at this time. Because the cause is not known, there is no way to prevent most cases of ALL.
 
How is Acute Lymphocytic Leukemia Found?
 
At this time, there are no special tests that can find acute leukemia early. The best course of action is to report any symptoms to the doctor right away.

Leukemia can cause many signs and symptoms, some of them very general in nature. Keep in mind that the symptoms mentioned below are most often caused by something other than cancer.

General symptoms of ALL can include:

• Weight loss
• Fever
• Loss of appetite
• Anemia
• Infection
• Bruising
• Bleeding
• Frequent or severe nosebleeds
• Bleeding from the gums

Most symptoms of ALL are caused by a shortage of normal blood cells, a result of the crowding out of normal blood cell-producing bone marrow by leukemia cells. As a result, the person doesn't have enough properly working red blood cells, white blood cells, and platelets.

Anemia is a result of a shortage of red blood cells. Anemia causes shortness of breath, fatigue, and a pale skin color.

Not having enough normal white blood cells can increase the risk of infection. Although people with leukemia may have very high white blood cell counts, the cells are not normal and do not protect against infection very well.

Not having enough blood platelets can lead to bruising, bleeding, frequent or severe nosebleeds, and bleeding from the gums.

ALL can spread outside of the bone marrow to other organs. If it spreads to the brain or spinal cord (central nervous system), it can cause symptoms such as:

• Headaches
• Weakness
• Seizures
• Vomiting
• Trouble keeping one's balance
• Blurred vision
• Bone pain or joint pain
• Swelling of the liver and spleen
  

  T-Lymphocytes

Some people have bone pain or joint pain caused by the spread of cancer cells to the surface of the bone or into the joint.

Leukemia can also cause swelling of the liver and spleen. If the disease has spread to the lymph nodes, these nodes may be swollen.

The T-cell type of ALL often involves the thymus, a gland found in the center of the chest, near the heart. An enlarged thymus can press on the nearby windpipe, causing coughing, shortness of breath, or even suffocation. A large vein, the superior vena cava (SVC) that carries blood from the head and arms back to the heart, also passes next to the thymus. If leukemia cells compress the SVC, swelling of the head and arms (SVC syndrome) can result. This can affect the brain and is life threatening. People with SVC syndrome need treatment right away.

What Testing Will Be Done if Acute Lymphocytic Leukemia is Suspected?
 
If there is reason to think that you might have leukemia, the doctor will need to take samples of cells from your blood and bone marrow to find out if the disease is really present.

Bone marrow tests: In bone marrow aspiration, a thin needle is used to draw up a small amount of liquid bone marrow. During a bone marrow biopsy, a small cylinder of bone and marrow (about ½ inch long) is removed with a slightly larger needle.

Both samples are usually taken at the same time from the back of the hipbone.

• The patient lies face down and the area is cleaned with a special soap.
• Before the sample is taken, the doctor injects an anesthetic into area near the back of the hipbone to numb it.
• Then the doctor makes a small cut in order to insert a needle.
• The needle is moved through the bone with a twisting motion.
• Sometimes the needle going into the bone is painful, but it only lasts a short time.
• During aspiration, the sucking out is often painful for a brief moment.

These tests are used to tell whether leukemia is present and also, if you are having treatment, how well the disease is responding.

Excisional lymph node biopsy: In this procedure, an entire lymph node is removed. If the node is near the skin's surface, a simple operation can be done by numbing just the area around the node. But if the node is inside the chest or abdomen, the patient will need general anesthesia (the patient is asleep). This test is only rarely needed for people with leukemia.

Spinal tap (lumbar puncture): In this procedure, a small needle is placed into the spinal cavity in the lower back to draw out some cerebrospinal fluid. The fluid is examined for leukemia cells.

Lab tests: Doctors use a number of very precise lab tests to diagnose and classify leukemia.

Blood cell counts and other blood tests: Changes in the numbers of different blood cell types and how the cells look under a microscope can suggest leukemia. Most people with acute lymphocytic leukemia (ALL) have too many white blood cells, not enough red cells, and not enough platelets. Also, many of the white cells will be blasts, a type of immature cell not normally found in circulating blood. These cells don't work the way they should.

People already known to have leukemia will have tests done to measure the amount of certain chemicals in the blood. These tests do not tell if they have leukemia but can help tell how well their kidneys and liver are working.

A doctor with special training in blood diseases looks at all of the biopsy samples (bone marrow, lymph node tissue, blood, and cerebrospinal fluid) under a microscope. The doctor looks at the size and shape of the cells as well as other features to classify the cells into specific types. An important goal of this process is to see whether the cells appear mature or not. The most immature cells are called blasts. The number of blasts in the bone marrow is important in telling if a person has leukemia.

Having at least 20% to 30% of blasts in the marrow is generally the benchmark for a diagnosis of ALL.

Other special tests which look at blood, marrow, and even DNA help tell which type of leukemia a person has. These are complex medical and chemical tests. Your doctor can tell you which of these you might need.

Imaging studies: Imaging studies are ways of producing pictures of the inside of the body.

Because leukemia does not usually form tumors, imaging tests are not always helpful. Imaging studies might be done in people with ALL, but they are done more often to look for infections or other problems rather than for the leukemia itself.

• X-rays may be done to see if there is a lung infection. The x-ray can also show enlarged lymph nodes in the chest.
• CT (computed tomography) scans are special kinds of x-rays in which a beam moves around the body, taking pictures from different angles. The pictures are combined by a computer into an image of a slice of the body. CT scans are helpful in looking at internal organs. They can show pockets of infection, enlarged organs, and any large collection of leukemia cells.
• MRI (magnetic resonance imaging) is a method that uses powerful magnets and radio waves to produce detailed, computer-generated pictures of the body. MRI scans are helpful in looking at the brain and spinal cord. MRI scans take longer than CT scans. Also, you may be placed inside a tube, which can feel confining.
• Gallium scans and bone scans involve injecting a radioactive chemical into the blood. The chemical collects in areas of cancer or infection, where it can be seen by a special camera. These tests are useful when a person has bone pain that might be caused by either infection or cancer involving bones.
• Ultrasound uses sound waves to produce images of internal organs. This test can tell solid from fluid-filled masses. It can help to show whether the kidneys, liver, or spleen are enlarged. This is an easy test to have done. You simply lie on a table and a kind of wand is moved over the part of your body being examined.

How is Acute Lymphocytic Leukemia Classified?
 
Most types of cancer are assigned a numbered stage based on the size of the tumor and how far it has spread. But there is no need to stage leukemia in this way because it already involves all the bone marrow and, in many cases, it has also spread to other organs.

Several years ago, an international conference of doctors who specialize in leukemia was held to decide on the best system for classifying acute leukemia. They decided upon 3 subtypes for ALL.

For leukemia, lab tests focus on finding out the exact type and subtype of leukemia, which in turn helps the doctor predict which treatments will work best.

Certain features of the disease separate patients who are likely to have a good response to treatment from those likely to have a poor response. These are called prognostic factors. These features include the patient's age, white blood cell count, certain test results, and initial response to chemotherapy.

How is Acute Lymphocytic Leukemia Treated?
 
As noted before, acute lymphocytic leukemia is not a single disease. It is really a group of diseases and people with different subtypes vary in how they respond to treatment. Treatment options are based on the subtype as well as on the prognostic features.

• Chemotherapy is the major treatment for ALL.
• Surgery and radiation may be used in some cases.

Chemotherapy refers to the use of drugs to kill cancer cells. Usually the drugs are given into a vein or by mouth. Once the drugs enter the bloodstream, they spread throughout the body. Chemotherapy for ALL involves the use of several drugs given over a long period of time.

Side Effects of Chemotherapy

While chemotherapy drugs kill cancer cells, they can also damage normal cells. This happens because they target rapidly growing cells such as cancer cells but in the process they also damage other fast growing cells.

The side effects of chemotherapy depend on the type and dose of drugs given and the length of time they are taken. These side effects might include:

• Hair loss
• Mouth sores
• Higher risk of infection (due to low white blood cells)
• Easy bruising or bleeding (due to low blood platelets)
• Tiredness (due to low red blood cells)
• Loss of appetite
• Nausea
• Vomiting

The side effects usually go away after treatment ends. Be sure to talk to your doctor if you are having trouble with side effects because there are often ways to manage them during treatment. For example, there are drugs than can be taken along with the chemotherapy to prevent or reduce nausea and vomiting. Drugs known as growth factors are sometimes given to keep blood counts higher and reduce the chance of infection.

Other ways you can reduce the risk of infection are by avoiding exposure to germs as much as possible and by carefully washing your hands and not eating uncooked fruits and vegetables. While in treatment you should also avoid large crowds and people who are sick.

During and after treatment, you might also get antibiotics as added protection. If your platelet counts are low, you might get platelet transfusions to protect against bleeding. Low red blood cell counts, causing shortness of breath and tiredness, can be treated with drugs or with transfusions.

Tumor lysis syndrome is a side effect caused by the rapid breakdown of leukemia cells due to treatment. When these cells die, they release substances into the bloodstream that can affect the kidneys, heart, and nervous system. Extra fluids or certain drugs that help rid the body of these toxins can help prevent this problem.

Finally, some people treated for ALL could later develop AML (acute myeloid leukemia). Less often, people cured of leukemia might later develop non-Hodgkin lymphomas or other cancers.

Targeted Therapy

A newer drug called imatinib (Gleevec) has been used to successfully treat chronic myeloid leukemia (CML). Clinical trials are going on now to see if this drug will be helpful in treating some people with ALL as well. Early reports have shown a better outcome when imatinib was used. This drug also seems to cause fewer side effects than other chemotherapy drugs. Possible side effects include diarrhea, nausea, muscle pain, and fatigue, but these are often mild.

Monoclonal antibodies are large proteins made in the lab. They attach to certain molecules on the surface of leukemia cells. These antibodies have been used to treat lymphomas. Researchers are now looking at whether they might be useful in treating some patients with ALL. Early results have been favorable, but it’s still too early to know for sure.

Surgery

Surgery is not generally used to treat leukemia because this is a disease of blood and bone marrow and it is not possible cure it with surgery. But surgery may be used to help deliver treatment. A plastic tube can be placed into a large vein. The tube, called a venous access device, allows chemotherapy drugs or other medicines to be given and blood samples removed without the need for many needle sticks. The patient will need to learn how to take care of the device to prevent it from getting infected.

Radiation Therapy

Radiation therapy is the use of high energy x-rays to kill cancer cells. It is sometimes used to treat leukemia that has spread to the brain and spinal cord or to the testicles.

Radiation to several parts of the body is often done before a bone marrow or blood stem cell transplant (see below). It is also used, though rarely, in an emergency to shrink a mass if it is pressing on the windpipe. But more often chemotherapy is used instead.

Bone Marrow or Peripheral Blood Stem Cell Transplantation

As noted earlier, chemotherapy can harm normal cells as well as cancer cells.

Stem cell transplantation (SCT) offers a way for doctors to use high doses of chemotherapy. Although the drugs destroy the patient's bone marrow, transplanted stem cells can restore the bone marrow’s ability to make blood. Transplants using the patient’s own stem cells are sometimes used for people with acute leukemia that is in remission.

The treatment works like this:

• Stem cells are collected from the bone marrow, or from the bloodstream in a process called apheresis.
• These stem cells can come from either the patient or from a suitable donor.
• The stems cells are frozen and stored.
• Patients are then given very high doses of chemotherapy to kill the cancer cells.
• They also receive total body radiation to kill any remaining cancer cells.
• After treatment, the stored stem cells are given to the patient as a blood transfusion.
• Then the waiting period begins as the stem cells settle in the patient's bone marrow and start to grow and produce blood cells.

People who receive a donor's stem cells are given drugs to prevent rejection as well as other medicines as needed to prevent infections. Usually around 10 to 21 days after the stem cells are given, they start making new white blood cells. Then they begin making platelets, and finally, red blood cells.

Patients having SCT have to be kept away from germs as much as possible until their white blood cell count is at a safe level. They are kept in the hospital until the white cell count reaches a certain number, usually around 1,000. After they go home, they will be seen in the outpatient clinic almost every day for several weeks.

Stem cell transplantation is still a fairly new and complex treatment. If the doctors think that a person with leukemia might be helped by this treatment, it is important that it be done at a hospital where the staff has experience with the procedure. Some transplant programs may not have experience in certain transplants, especially those from unrelated donors.

Stem cell transplantation is very expensive and requires a long hospital stay. Because some insurance companies see it as an experimental treatment, they might not pay for it.

Side Effects of Stem Cell Transplantation

Side effects from stem cell transplantation can be divided into early and long-term effects.

The early side effects are basically the same as those caused by any other type of high-dose chemotherapy. But other side effects can last for a long time, or they may not occur until years after the transplant.

These long-term side effects can include the following:

• Radiation damage to the lungs, causing shortness of breath
• Graft-versus-host disease (GVHD), which occurs only in a donor transplant
• Damage to the ovaries causing infertility and the loss of menstrual periods
• Damage to the thyroid gland that causes problems with changing food into energy
• Cataracts (damage to the eye that can affect vision)
• Bone damage (if damage is severe, the patient will need to have part of the bone and joint replaced)
• Graft-versus-host disease is the main problem of a donor stem cell transplant. It happens when the immune system of the patient is taken over by that of the donor. The donor immune system then starts to attack the patient’s other tissues and organs.

Symptoms can include:

• Severe skin rashes with itching 
• Severe diarrhea
• The liver and lungs may also be damaged
• The patient may also become tired and have aching muscles

Drugs that affect the immune system may be given to try to control it. On the plus side, this disease also causes any remaining leukemia cells to be killed by the donor immune system.

For ALL, chemotherapy treatments are given in the following phases:

Remission induction: The purpose of the first phase is to bring about a remission - the disappearance of the signs and symptoms of the cancer. A remission may not be a cure.

Consolidation: The goal of this phase is to get rid of leukemia cells from places where they can "hide." This lasts from one to a few months.

Maintenance: Once the number of leukemia cells has been reduced by the first 2 phases of treatment, this last phase can begin. Maintenance, which usually consists of lower doses of chemotherapy drugs, lasts about 2 years.

In general, about 8 out of 10 patients will have a complete response to these treatments. That means that leukemia can no longer be seen in their bone marrow. But about half of these patients will have a relapse, so the overall cure rate is around 30%.

Central nervous system treatment: Because ALL often spreads to the coverings of the brain and spinal cord, patients often receive chemotherapy in the spinal fluid or radiation therapy of the head as a method of prevention.

Finally, some patients who are at high risk for relapse (because of poor prognostic factors) may have a stem cell transplant.

What if the Leukemia Doesn’t Respond or Comes Back After Treatment?

If the leukemia comes back after treatment, it will most often do so in the bone marrow and blood. Once in a while, the brain or spinal fluid will be the first place it returns.

If the leukemia had gone away and has now come back, it may be possible to bring about another remission, although most doctors think this remission will be only temporary. In these cases most doctors will consider a stem cell transplant.

If the leukemia keeps coming back or doesn’t go away, chemotherapy will finally not be very helpful. If a stem cell transplant is not an option, entering a clinical trial (see section on Clinical Trials) might be a good idea.

If neither of these options is the right one, then it may be time to focus on relieving symptoms. The doctor may suggest more mild chemotherapy to slow the growth of the leukemia. If there is pain, then it’s important to treat it with pain killing medicines. Sometimes medicines or blood transfusions are needed to correct low blood counts and tiredness. If depression is a problem, that can be treated as well. Nausea and loss of appetite can be helped by high-calorie food supplements and medicines. Antibiotics may be needed to treat infection.

Acute Myeloid Leukemia (AML)
 
Leukemia is a type of cancer that starts in the soft, inner part of the bones (bone marrow) but often moves quickly into the blood. It can then spread to other parts of the body, such as the lymph nodes, the spleen, liver, central nervous system and other organs. Both children and adults can get leukemia.

"Acute" means that the cancer develops quickly, and if not treated, could be fatal in a few months. Acute myeloid leukemia (AML) is a type of cancer that starts from cells that normally develop into blood cells.

Leukemia is a complex disease with many different types and sub-types. The kind of treatment given and the outlook for the person with leukemia vary greatly according to the exact type and other factors.

How Many People Get Acute Myeloid Leukemia (AML)?
 
In 2008 there will be about 44,270 new cases of all types of leukemia in the United States. About half of these will be acute leukemias. There will be about 13,230 new cases of acute myelogenous leukemia (AML). Nine out of 10 cases of AML are found in adults. There will be about 8,820 deaths from AML in the United States this year. The average age of a patient with AML is 67. AML is slightly more common among men than among women.

AML can be kept in remission for a long time or cured in some adults. Depending on certain features of the leukemia cells, some patients have a better and some a worse outlook (prognosis). Overall, the 5-year survival rate in adults under 65 is about 33%. In people over 65 it is 4%. The 5-year survival rate refers to the percentage of patients who live at least 5 years after their cancer is found. Of course, many people live much longer than 5 years.

What Causes Acute Myeloid Leukemia?
 
A risk factor is something that increases a person's chance of getting a disease. Some risk factors, like smoking, can be controlled. Others, such as a person's age, can't be changed.

• Smoking is a proven risk factor for AML. Although many people know that smoking causes lung cancer, few realize that it can affect cells that do not come into direct contact with smoke. Cancer-causing substances in tobacco smoke get into the bloodstream and spread to many parts of the body. Smoking causes about 1 in 5 cases of AML.
• Long-term exposure to high levels of benzene
• High-dose radiation exposure (such as from an atomic blast or nuclear reactor accident)
• People who have had other cancers and were treated with certain chemotherapy drugs are more likely to develop AML. Most of these cases of AML happen within 9 years after treatment.
• There is some concern about very high-voltage power lines as a risk factor for leukemia. The National Cancer Institute has several large studies going on now to look into this question. So far, the studies show either no increased risk or a very slightly increased risk. Clearly, most cases of leukemia are not related to power lines.

Can Acute Myeloid Leukemia Be Prevented?
 
Most people who develop leukemia do not have any of the above risk factors. The cause of their leukemia remains unknown at this time. Because the cause is not known, there is no way to prevent most cases of leukemia. There is one important exception: smoking. About 20% of adult acute myeloid leukemia cases are linked to smoking.
 
How is Acute Myeloid Leukemia Found?
 
At this time, there are no special tests that can find acute myeloid leukemia early. The best course of action is to report any symptoms to the doctor right away.

Leukemia can cause many signs and symptoms, some of them very general in nature. Keep in mind that the symptoms mentioned below are most often caused by something other than cancer.

General symptoms of AML can include:

• Weight loss
• Fever
• Loss of appetite
• Anemia 
• Increased risk of infection
• Bruising
• Bleeding
• Frequent or severe nosebleeds
• Bleeding from the gums
• Bone pain or joint pain

Most symptoms of acute leukemia are caused by a shortage of normal blood cells, a result of the crowding out of normal blood cell-producing bone marrow by leukemia cells. As a result, the person doesn't have enough properly working red blood cells, white blood cells, and platelets. Anemia is a result of a shortage of red blood cells. Anemia causes shortness of breath, fatigue, and a pale skin color.

Not having enough normal white blood cells can increase the risk of infection. Although people with leukemia may have very high white blood cell counts, the cells are not normal and do not protect against infection very well.

Not having enough blood platelets can lead to bruising, bleeding, frequent or severe nosebleeds, and bleeding from the gums.

Some people have bone pain or joint pain caused by the spread of cancer cells to the surface of the bone or into the joint. Leukemia can also cause swelling of the liver and spleen. If the disease has spread to the lymph nodes, these nodes may be swollen. One type of AML is prone to spread to the gums, causing them to swell, become painful, and bleed. Spread to the skin can cause small colored spots that look like common rashes.

AML can spread outside of the bone marrow to other organs. If it spreads to the brain or spinal cord (central nervous system), it can cause a variety of symptoms such as headaches, weakness, seizures, vomiting, trouble keeping one's balance, and blurred vision. This is not common in people with AML.

What tests will be done if Acute Myeloid Leukemia is suspected?
 
If there is reason to think that you might have leukemia, the doctor will need to take samples of cells from your blood and bone marrow to find out if the disease is really present.

Blood cell counts and other blood tests: Changes in the numbers of different blood cell types and how the cells look under a microscope can suggest leukemia. Most people with AML will have too many white blood cells, not enough red cells, and not enough platelets. Also, many of the white cells will be blasts, a type of immature cell not normally found in circulating blood. These cells don't work the way they should.

People already known to have leukemia will have tests done to measure the amount of certain chemicals in the blood. These tests do not tell if they have leukemia, but can help tell how well their kidneys and liver are working.

Bone marrow tests: In bone marrow aspiration, a thin needle is used to draw up a small amount of liquid bone marrow. During a bone marrow biopsy, a small cylinder of bone and marrow (about ½ inch long) is removed with a slightly larger needle.

Both samples are usually taken at the same time from the back of the hipbone.

• The patient lies on his or her side and the area is cleaned with a special soap.
• Before the sample is taken, the doctor injects an anesthetic into the area near the back of the hipbone to numb it.
• Then the doctor makes a small cut in order to insert a needle.
• The needle is moved through the bone with a twisting motion.
• Sometimes the needle going into the bone is painful, but it only lasts a short time.
• During aspiration, the sucking out is often painful for a brief moment.

These tests are used to tell whether leukemia is present and also, if you are having treatment, how well the disease is responding.

Lumbar puncture: In this procedure, a small needle is placed into the spinal cavity in the lower back to draw out some cerebrospinal fluid. The fluid is examined for leukemia cells. This test is not usually done for people with AML.

Lab tests: Doctors use a number of very precise lab tests to diagnose and classify leukemia.

A doctor with special training in blood diseases examines all of the biopsy samples (bone marrow, blood, and cerebrospinal fluid) under a microscope. The doctor looks at the size and shape of the cells as well as other features to classify the cells into specific types. An important goal of this process is to see whether the cells appear mature or not. The most immature cells are called blasts. The number of blasts in the bone marrow is important in telling if a person has leukemia.

Other special tests, such as flow cytometry, may also help tell which type of leukemia a person has.

Imaging studies: Imaging studies are ways of producing pictures of the inside of the body. There are several kinds of these studies that might be done in people with leukemia. They are done most often to look for infections or other problems rather than for the leukemia itself.

• X-rays may be done if the doctor thinks there might be a lung infection.
• CT (computed tomography) scans are special kinds of x-rays in which a beam moves around the body, taking pictures from different angles. The pictures are combined by a computer into an image of a slice of the body. CT scans are helpful in looking at internal organs. They can show pockets of infection, enlarged organs, and any large collection of leukemia cells.
• MRI (magnetic resonance imaging) is a method that uses powerful magnets and radio waves to produce detailed, computer-generated pictures of the body. MRI scans are helpful in looking at the brain and spinal cord. MRI scans take longer than CT scans. Also, you may be placed inside a tube, which can feel confining.
• Gallium scans and bone scans involve injecting a radioactive chemical into the blood. The chemical collects in areas of cancer or infection, where it can be seen by a special camera. These tests are useful when a person has bone pain that might be caused by either infection or cancer involving bones.
• Ultrasound uses sound waves to produce images of internal organs. This test can tell solid from fluid-filled masses. Ultrasound is also used to show whether the kidneys, liver, or spleen have been affected by leukemia. This is an easy test to have done. You simply lie on a table and a kind of wand is moved over the part of your body being examined.

How is Acute Myeloid Leukemia Classified?
 
Most types of cancer are assigned a numbered stage based on the size of the tumor and how far it has spread. But there is no need to stage leukemia in this way because it already involves all the bone marrow and, in many cases, it has also spread to other organs. Lab tests focus on finding out the exact type (and subtype) of leukemia. This in turn helps predict which treatments will work best and the outlook (prognosis) for the patient.

Several years ago, an international conference of doctors who specialize in leukemia was held to decide on the best system for classifying acute leukemia. They decided upon 8 subtypes for AML, labeled M0 through M7, based on the type of cell from which the leukemia started. This system (the French-American-British or FAB system) was based at first on how the cells looked under the microscope. But now doctors use many advanced tests to classify AML.

Some subtypes of AML produce certain symptoms. For example, bleeding or blood clotting problems often happen to people with the M3 subtype of AML. Finding out if a person has M3 leukemia is very important for 2 reasons. First, serious problems can often be prevented by the right treatment. Second, M3 leukemias usually respond to certain drugs related to vitamin A. Using these drugs allows doctors to use lower doses of chemotherapy drugs and thus reduce side effects.

Certain features of the disease separate patients who are likely to have a good response to treatment from those likely to have a poor response. These are called prognostic factors. These factors include the patient's age, white blood cell count, certain test results, response to chemotherapy, and whether or not the person had been treated earlier for another cancer.

While some patients might find detailed information about subtypes and prognostic factors helpful, others may find it a bit overwhelming. The American Cancer Society has more information about these subtypes and prognostic factors in a separate document, available through our toll-free number or on our Web site.

How is Acute Myeloid Leukemia Treated? 
 
As noted before, acute myeloid leukemia is not a single disease. It is really a group of diseases, and people with different subtypes vary in how they respond to treatment. Treatment options are based on the subtype as well as on the prognostic features. Several different types of treatment may be used in people with AML.

Treatment of AML is Divided into Two Phases:

• Remission induction
• Post-remission therapy

Remission induction: This first phase, which is meant to destroy most of the normal and leukemic bone marrow cells, usually lasts one week. During this time and in the weeks right after, the patient's blood cell counts will be very low. The doctor will take measures to protect against complications. If 1 week of treatment fails to bring about a remission, the process is repeated 1 or 2 more times. Induction works for about 6 or 7 out of 10 patients.

Consolidation (post-remission) therapy: While the first phase of treatment usually destroys nearly all of the cancer cells, there may still be some "hidden" leukemic cells. The purpose of the second phase is to destroy these cells and prevent a relapse. The options for post-remission treatment are either further chemotherapy or stem cell transplantation, described later in this article. Four years after this treatment, 40% of young patients (younger than 60 years) will not show any signs of leukemia. In older adults, this number is around 15%.

Doctors look at several factors when recommending post-remission treatment for a patient. These factors include:

• How much chemotherapy it took to bring about a remission
• Whether there is a stem cell donor (brother or sister or unrelated donor) who matches the patient’s tissue type
• Whether it looks as if leukemia-free bone marrow stem cells can be collected from the patient
• Whether there are good or poor prognostic factors
• The patient’s age
• What the patient prefers

Maintenance therapy: In the past it was thought that a short burst of intense therapy as described above was the best way to treat AML. But a recent study from Germany of over 800 patients found that patients had better outcomes if they also received low doses of chemotherapy for 3 years after their induction and consolidation courses.

Surgery

Surgery is not generally used to treat leukemia because this is a disease of blood and bone marrow and it is not possible to bring about a cure with surgery. But surgery may be used to help deliver treatment. A plastic tube can be placed into a large vein. The tube, called a venous access device, allows chemotherapy drugs or other medicines to be given and blood samples removed without the need for many needle sticks. The patient will need to learn how to take care of the device to prevent it from getting infected.

Radiation Therapy

Radiation therapy, the use of high energy x-rays to kill cancer cells, has a limited role to play in the treatment of people with leukemia.

For adults with acute leukemia, radiation might be used to treat cancer that has spread beyond the bone marrow. It might also be used, though rarely, in an emergency to treat pressure on the windpipe. But more often chemotherapy is used instead.

Chemotherapy

Chemotherapy refers to the use of drugs to kill cancer cells. Usually the drugs are given into a vein or by mouth. Once the drugs enter the bloodstream, they spread throughout the body. The first chemotherapy for AML is a combination of 2 or 3 drugs given over about a week at the hospital.

Treatment of M3 Leukemia

Patients with M3 leukemia can develop serious blood clotting or bleeding problems. This can usually be prevented or treated by giving them a blood thinner. Other treatments might include transfusions of platelets or other blood products.

The treatment of M3 leukemia differs from usual AML treatment because a non-chemotherapy drug known as ATRA (related to vitamin A) is also used. For best results, ATRA is combined with other chemotherapy drugs. Another drug, arsenic trioxide, has been effective in treating patients with APL whose leukemia comes back after the first treatment

Side effects from ATRA can include retinoic acid syndrome. This very serious side effect can cause breathing problems from fluid buildup, low blood pressure, and kidney damage.

After remission, further treatment consists of 2 or more courses of chemotherapy followed by maintenance with ATRA for a least one year. About 70% to 90% of patients are cured with this approach.

Side Effects of Chemotherapy

While chemotherapy drugs kill cancer cells, they can also damage normal cells. This happens because they target rapidly growing cells such as cancer cells, but in the process they also damage other fast growing cells.

Bone marrow, the lining of the mouth and intestines, and hair follicles all grow rapidly and are likely to be affected by chemotherapy. As a result, people being treated with chemotherapy may have some side effects:

• Higher risk of infection (from low white blood cell counts)
• Bruising or bleeding easily (from low blood platelets)
• Tiring easily (from low red blood cell counts)
• Hair loss
• Nausea
• Vomiting
• Loss of appetite

These side effects usually go away shortly after treatment ends. There are often ways to manage these side effects during treatment. For example, there are drugs than can be taken along with the chemotherapy to prevent or reduce nausea and vomiting. Drugs known as growth factors are sometimes given to keep blood counts higher and reduce the chance of infection.

Other ways you can reduce the risk of infection are by avoiding exposure to germs as much as possible and by carefully washing your hands and not eating uncooked fruits and vegetables. While in treatment you should also avoid large crowds and people who are sick. It’s best to also avoid fresh flowers and plants because they carry mold.

During and after treatment, you might also get antibiotics as added protection. If your platelet counts are low, you might get platelet transfusions to protect against bleeding. Low red blood cell counts, causing shortness of breath and tiredness, can be treated with drugs or with transfusions.

Tumor lysis syndrome is a side effect caused by the rapid breakdown of leukemia cells due to treatment. When these cells die, they release substances into the bloodstream that can affect the kidneys, heart, and nervous system. Extra fluids or certain drugs that help rid the body of these toxins can help prevent this problem.

Organs that could be damaged by chemotherapy include the kidneys, liver, testes, ovaries, brain, heart, and lungs. By watching the patient carefully, the doctor may be able to prevent many of these side effects. If serious side effects happen, though, the drugs may have to be reduced or stopped—at least for a while.

Monoclonal Antibodies

These are proteins made in the lab and designed to attach to certain molecules on the surface of AML cells. Some of these antibodies have radioactive chemicals or cell poisons attached to them so that when they are injected into the patient, they attach to the cancer cells and kill them. One such antibody (Mylotarg) has recently been approved for use in older adults with AML who have relapsed after treatment or who might not be able to take the side effects of further chemotherapy. Studies are still going on to look at the best use of this approach.

Bone Marrow or Peripheral Blood Stem Cell Transplantation

As noted earlier, chemotherapy can harm normal cells as well as cancer cells. Stem cell transplantation (SCT) offers a way for doctors to use high doses of chemotherapy. Although the drugs destroy the patient's bone marrow, transplanted stem cells can restore the bone marrow’s ability to make blood. Transplants using the patient’s own stem cells are sometimes used for people with acute leukemia that is in remission.

The Treatment Works Like This:

• Stem cells for are collected from the bone marrow or from the bloodstream in a process called apheresis.
• These stem cells can come from either the patient or from a suitable donor.
• The stem cells are frozen and stored.
• The patient is then given very high doses of chemotherapy to kill the cancer cells.
• They also receive total body radiation to kill any "hidden" cancer cells.
• After treatment, the stored stem cells are given to the patient as a blood transfusion.
• Then the waiting period begins as the stem cells settle in the patient's bone marrow and start to grow and produce blood cells.

People who receive a donor's stem cells are given drugs to prevent rejection as well as other medicines as needed to prevent infections. Usually around 10 to 21 days after the stem cells are given they start making new white blood cells. Then they begin making platelets, and finally, red blood cells.

Patients having SCT have to be kept away from germs as much as possible until their white blood cell count is at a safe level. They are kept in the hospital until the white cell count reaches a certain number, usually around 1,000. After they go home, they will be seen in the outpatient clinic almost every day for several weeks.

Stem cell transplantation is still a fairly new and complex treatment. If the doctors think that a person with leukemia might be helped by this treatment, it is important that it be done at a hospital where the staff has experience with the procedure. Some transplant programs may not have experience in certain transplants, especially those from unrelated donors.

Stem cell transplantation is very expensive and requires a long hospital stay. Because some insurance companies see it as an experimental treatment, they might not pay for it.

Side Effects of Stem Cell Transplantation

Side effects from SCT can be divided into early and long-term effects. Early side effects are basically the same as those from any other type of high-dose chemotherapy. They are caused by damage to the bone marrow and other rapidly growing tissues of the body.

But other side effects can go on for a long time. Sometimes they don't show up until years after the transplant. The long-term side effects could include the following:

• Radiation damage to the lungs, causing shortness of breath
• Graft-versus-host disease, which happens only in donor transplants. This serious side effect can occur when the donor's immune system cells attack tissues of the patient's skin, liver, mouth, or other organs. Symptoms include weakness, fatigue, dry mouth, rashes, infection, and muscle aches.
• Damage to the ovaries causing infertility and loss of menstrual periods
• Damage to the thyroid gland that causes problems with metabolism
• Cataracts (damage to the lens of the eye)
• Bone damage; if damage is severe, the patient will need to have part of the bone and joint replaced.
• Graft-versus-host disease is the main problem of a donor stem cell transplant. It happens when the immune system of the patient is taken over by that of the donor. The donor immune system then starts to attack the patient’s other tissues and organs.

Symptoms can include severe skin rashes with itching and severe diarrhea. The liver and lungs may also be damaged. The patient may also become tired and have aching muscles. If severe enough, the disease can be fatal. Drugs that affect the immune system may be given to try to control it. On the plus side, this disease also causes any remaining leukemia cells to be killed by the donor immune system. So, sometimes the doctors want to see some graft-versus-host disease occur.

What if the Leukemia Doesn’t Respond or Comes Back After Treatment?

If the disease comes back it will most often be in the bone marrow and blood. Sometimes the brain or spinal fluid will be the first place it is seen. This will be treated with chemotherapy given directly into the spinal fluid. If the leukemia never went away with the first treatment, then more treatment is not likely to work, even with new drugs. If the leukemia did go away and has now come back, another remission might be possible, although most doctors think it would be only temporary. They might suggest a stem cell transplant in this case.

If the leukemia keeps coming back or doesn’t go away, chemotherapy will finally not be very helpful. If a stem cell transplant is not an option, entering a clinical trial (see section on Clinical Trials) might be a good idea.

If neither of these options is the right one, then it may be time to focus on relieving symptoms. The doctor may suggest more mild chemotherapy to slow the growth of the cancer. If there is pain, then it’s important to treat it with pain killing medicines. Sometimes medicines or blood transfusions are needed to correct low blood counts and tiredness. If depression is a problem, that can be treated as well. Nausea and loss of appetite can be helped by high-calorie food supplements and medicines. Antibiotics may be needed to treat infection.

Chronic Lymphocytic Leukemia (CLL)
 
Chronic lymphocytic leukemia (CLL) is a type of cancer that starts in lymphocytes (white blood cells) of the bone marrow. It then invades the blood. It can spread to the lymph nodes, the spleen, liver, and other parts of the body.

Doctors have learned that there are probably two different kinds of CLL.

• One kind is very slow growing and rarely needs to be treated. The average survival for people with this kind of CLL is around 13 to 15 years.
• Another kind is a faster growing and more serious disease. People with this form of CLL have an average survival of only about 6-8 years. The leukemia cells from these 2 types look alike. But certain new lab tests can tell them apart.

Hairy cell leukemia (HCL), like CLL, is a cancer of the lymphocytes that grows slowly. But HCL is often thought of differently from CLL because of differences in symptoms and treatment.

How Many People Get Chronic Lymphocytic Leukemia?
 
The American Cancer Society estimates that, in 2008, there will be about 15,1100 new cases of chronic lymphocytic leukemia (CLL) in the US and about 4,390 people will die from it.

Chronic lymphocytic leukemia affects only adults. The average age of patients is about 72. It is rarely seen in people under the age of 40.
 
What Causes Chronic Lymphocytic Leukemia? 

There are no known risk factors for CLL that are linked to lifestyle, but there are a very few factors in the environment that are linked to chronic leukemia.

• Chemicals used in farming, such as herbicides and insecticides, may increase the risk of CLL.
• Exposure to Agent Orange, an herbicide used during the Vietnam War, has been linked to an increased risk of CLL.
• The only known inherited risk factor for chronic leukemia is having first-degree relatives (parents, siblings, or children) who have had CLL.

Can Chronic Lymphocytic Leukemia be Prevented?

Although many types of cancer can be prevented by lifestyle changes to avoid certain risk factors, there are no known risk factors for CLL that a person can change. So right now there is no way to prevent CLL from developing.

How is Chronic Lymphocytic Leukemia Found?
 
At this time, there are no special tests that can find chronic leukemia early. The best course of action is to report any symptoms to the doctor right away. Many people with CLL have no symptoms at the time their cancer is found. In these cases, the cancer is found by blood tests done for some other reason. Even when there are symptoms, they may be very general. Many of the symptoms of advanced CLL happen because the leukemia cells replace the bone marrow’s blood-producing cells. As a result, people do not have enough blood cells and platelets that are working as they should.

• Fatigue
• Weakness
• Weight loss
• Fever
• Bone pain
• Anemia
• Increased risk of infection. Although people with leukemia may have very high white blood cell counts, the cells are not normal and do not protect against infection very well.
• Not having enough blood platelets can lead to bruising, bleeding, frequent or severe nosebleeds, and bleeding from the gums.
• Some people have bone pain or joint pain caused by the spread of cancer cells to the surface of the bone or into the joint.
• Leukemia can also cause swelling of the liver and spleen. If the disease has spread to the lymph nodes, these nodes may be swollen.

Tests to Look for Leukemia

Bone marrow tests: In bone marrow aspiration, a thin needle is used to draw up a small amount of liquid bone marrow. The skin and the surface of the bone are first numbed, but the test can still be uncomfortable. During a bone marrow biopsy, a small cylinder of bone and marrow (about ½" long) is removed with a slightly larger needle.

Both samples are usually taken at the same time from the back of the hipbone. These tests are used to tell whether leukemia is present and also, if the person is having treatment, how well the disease is responding.

Excisional lymph node biopsy: For this test, an entire lymph node is removed. If the node is near the skin's surface, a simple operation can be done by numbing just the area around the node. But if the node is inside the chest or abdomen, the patient will need general anesthesia. This procedure is only rarely needed for people with CLL unless a lymph node has grown very large.

Lumbar puncture (spinal tap): During this test, a small needle is placed into the spinal cavity in the lower back to draw out some cerebrospinal fluid. The fluid is looked at for leukemia cells. This test is only done for patients with CLL if it appears that there may be leukemia cells in their brain or spinal cord or an infection in those areas.

Blood cell counts and blood cell examination: Changes