Leukemia is a type of cancer that affects the blood and bone marrow. Types of leukemia are named after specific blood cells that become cancerous and the rate at which leukemia progresses is different for each type of the disease. There are 4 main types of leukemia:

• Acute Lymphoblastic Leukemia (ALL)
  Acute lymphoblastic leukemia (also known as Acute Lymphocytic Leukemia or Acute Lymphoid Leukemia) is a cancer that begins in the bone marrow. Cells that normally form a type of white blood cell called a lymphocyte become cancerous and do not function properly. It progresses rapidly without treatment so early diagnosis and treatment is extremely important.
  
  For a brief but informative video on ALL click on the following link:
  https://www.youtube.com/watch?v=7nCvItKbEns 
   
• Chronic Lymphocytic Leukemia (CLL)
  Chronic Lymphocytic Leukemia is the most common form of leukemia in adults and is a type of blood cancer that begins in the bone marrow. Cells that normally form a type of white blood cell called a lymphocyte become cancerous and do not function properly. It can progress either slowly or quickly depending on the form it takes.  CLL doesn’t completely interfere with production of blood cells, and therefore is generally less severe than acute lymphoblastic leukemia. Many people with CLL live good-quality lives for years without medical care.
  
  For a brief but informative video on CLL from the Mayo Clinic, click on the link below:                
  http://www.youtube.com/watch?v=GCMuizn980c&feature=related
   
• Acute Myeloid Leukemia (AML)
  Acute Myeloid Leukemia (also known as Acute Myelogenous Leukemia) is a cancer of the bone marrow and blood. AML is a type of cancer in which the bone marrow makes abnormal immature (not fully developed) blood cells that do not become healthy blood cells. These cells build up in the bone marrow and blood so there is less room for healthy cells to function properly. AML progresses rapidly without treatment so it is important to get care and treatment as soon as possible.
  
  For a brief but informative video on pediatric AML from the Chicago School of Medicine, click on the link below: http://www.youtube.com/watch?v=NE5BtHcZZXo 
   
• Chronic Myeloid Leukemia (CML)
  Chronic Myeloid Leukemia (also known as Chronic Myelogenous Leukemia) is a cancer that begins in the bone marrow. Cells that normally mature into white blood cells (except lymphocytes), red blood cells and platelets do not mature completely. It usually progresses slowly because patients have more mature cells capable of carrying out some of their normal functions. CML is usually diagnosed in its chronic phase when treatment is very effective for most patients. CML occurs mostly in adults.
  
  For a brief but informative video on CML from the Mayo Clinic, click on the link below: http://www.youtube.com/watch?v=MGqyY57uTvU

There are other, less common types of leukemia but they are generally subcategories of one of the four main categories. Approximately 4,800 people in Canada develop leukemia each year.

What is Acute Leukemia?

Acute Leukemia is a rapidly progressing disease that results in the accumulation of immature, non-functional cells in the marrow and blood. As a result, the bone marrow often can no longer produce enough normal red blood cells, white blood cells, and platelets. Acute leukemia requires aggressive, timely treatment.

What is Chronic Leukemia?

This type of leukemia involves more mature blood cells. These blood cells replicate or accumulate more slowly and can function normally for a period of time. Some forms of chronic leukemia initially produce no symptoms and can go unnoticed or undiagnosed for years.

Is Leukemia Contagious?

Leukemia is not contagious. However, patients undergoing treatment are at a greater risk of infection because of the impact that the drugs have on our immune system. 

Is Leukemia Inherited?

No. There is little to no evidence that these diseases are inherited. There are genetic components to the diseases and often there are alterations in the DNA but the cause of these changes is unknown.

How Does Leukemia Develop?

Scientists don't understand the exact causes of leukemia. It can develop from a combination of genetic and environmental factors. Some leukemias may develop in patients who have received prior therapy for other cancers.

Leukemia occurs when cells in the bone marrow and blood acquire mutations in their DNA (the instructions inside each cell that guide its action). These abnormalities cause the cell to grow and divide uncontrollably and survive better than normal cells. The abnormal cells can crowd out healthy blood cells in the bone marrow, leading to fewer healthy blood cells and causing the signs and symptoms of leukemia.

What is Remission?

There are two classifications for remission:

• Complete remission means that tests, physical exams, and scans show there are no signs or symptoms of cancer. 
   
• Partial remission means that the cancer partly responded to treatment and you have less cancer throughout your body. 

Even if you are in remission or your disease is under control, regular follow-up care is critically important.