Leukemia is a group of hematological malignancies (blood cancer).

There are 4 main types of leukemia: acute myeloid (AML), acute lymphoblastic (ALL), chronic myeloid (CML) and chronic lymphocytic (CLL).

Acute Lymphoblastic Leukemia is the most common type of leukemia in children.

Worldwide, it is estimated that more than a quarter of a million people are diagnosed and over 200,000 die from leukemia every year.

Every minute someone is diagnosed with blood cancer and every day blood cancer takes many precious lives.

Leukemia causes almost one-third of all cancer deaths in children under the age 15.

Although leukemia is the most common cancer in childhood, more than 9 in 10 cases are diagnosed in adults.

Incidence rates for all types of leukemia tend to be higher among males than among females.

A bone marrow transplant can save the lives of people battling leukemia, lymphoma, and other blood cancers.

Every year more than 10,000 men, women and children could benefit from a bone marrow transplant.

70% of patients in need of a bone marrow transplant do not have a matching donor in their family.

Only 3 out of 10 will receive the transplant that can save their live.

Young people 18-24 years old are bone marrow donors that are needed the most.

WHAT IS LEUKEMIA?

Leukemia is a malignancy (cancer) of blood cells. In leukemia, abnormal blood cells are produced in the bone marrow. Usually, leukemia involves the production of abnormal white blood cells -- the cells responsible for fighting infection. However, the abnormal cells in leukemia do not function in the same way as normal white blood cells. The leukemia cells continue to grow and divide, eventually crowding out the normal blood cells. The end result is that it becomes difficult for the body to fight infections, control bleeding, and transport oxygen.

WHAT CAUSES LEUKEMIA?

The exact cause of leukemia is not known, but it is thought to involve a combination of genetic and environmental factors. Leukemia cells have acquired mutations in their DNA that cause them to grow abnormally and lose functions of typical white blood cells. Most cases of leukemia are not believed to be hereditary, but certain genetic mutations and conditions can be passed along to offspring that increase the chances of developing leukemia.

Exposure to radiation is known to increase the risk of developing AML, CML, or ALL. Increases in leukemia were observed in people surviving atomic bombs. Radiation therapy for cancer can also increase the risk of leukemia. Exposure to benzene, used commonly in the chemical industry, increases the risk of leukemia. Cigarette smoking is known to increase the risk of developing AML.

WHAT ARE THE SYMPTOMS OF LEUKEMIA?

The symptoms and signs of leukemia depend upon the type of leukemia. Slow-growing or chronic leukemia may not cause any symptoms at the outset, while aggressive or rapidly growing leukemia may lead to severe symptoms. The symptoms of leukemia arise from a loss of function of the normal blood cells or from accumulation of the abnormal cells in the body. Signs and symptoms of leukemia typically include fevers, night sweats, swollen lymph nodes that are usually painless, feelings of fatigue, tiredness, easy bleeding or bruising, causing bluish or purplish patches on the skin or tiny red spots on the skin, or recurring nosebleeds, frequent infections, bone or joint pain and weight loss that is otherwise unexplained, or loss of appetite. If leukemia cells have infiltrated the brain, symptoms such as headaches, seizures, confusion, loss of muscle control, and vomiting can occur.

HOW IS LEUKEMIA DIAGNOSED?

Physicians diagnose leukemia based on a medical history and a physical exam to look for signs of leukemia (lymph node enlargement, enlargement of spleen). The diagnosis of leukemia typically involves laboratory studies of a blood sample and of the the bone marrow. Abnormal numbers of blood cells may suggest a diagnosis of leukemia, and the blood sample may also be examined under the microscope to see if the cells appear abnormal. For a bone marrow aspirate, a long, thin needle is used to withdraw a sample of bone marrow from the hip bone, under local anesthesia. Cells from the blood and bone marrow are further tested if leukemia cells are present. These additional tests look for genetic alterations and expression of certain cell surface markers by the cancer cells (immunophenotyping). The results of these tests are used to help determine the precise classification of the leukemia and to decide on optimal treatment.

HOW IS LEUKEMIA TREATED?

There are a number of different medical approaches to the treatment of leukemia. Treatment will typically depend upon the type of leukemia, the patient's age and health status, as well as whether or not the leukemia cells have spread to the cerebrospinal fluid. The genetic changes or specific characteristics of the leukemia cells as determined in the laboratory can also determine the type of treatment that may be most appropriate.

Treatments for leukemia include chemotherapy (major treatment modality for leukemia), radiation therapy, biological therapy, targeted therapy, and stem cell transplant. Combinations of these treatments may be used. Surgical removal of the spleen can be a part of treatment if the spleen is enlarged. Watchful waiting may be an option for some people with a chronic leukemia who do not have symptoms. This involves close monitoring of the disease so that treatment can begin when symptoms develop.