Leukemia, leukaemia, cancer of blood or bone marrow:: cancer symptom, definition syndrome acute, chronic, treatment, type cause sign history society, foundation information fact early cure picture disease diagnosis research prognosis

Leukemia

Amazon.com Widgets

Leukemia or leukaemia (see spelling differences) is a cancer of the blood or bone marrow and is characterized by an abnormal proliferation (production by multiplication) of blood cells, usually white blood cells (leukocytes). It is part of the broad group of diseases called hematological neoplasms.

Symptoms

Damage to the bone marrow, by way of displacing the normal bone marrow cells with higher numbers of immature white blood cells, results in a lack of blood platelets, which are important in the blood clotting process. This means people with leukemia may become bruised, bleed excessively, or develop pinprick bleeds (petechiae).

White blood cells, which are involved in fighting pathogens, may be suppressed or dysfunctional. This could cause the patient's immune system (white blood cells etc.) to start attacking other body cells.

Finally, the red blood cell deficiency leads to anemia, which may cause dyspnea. All symptoms can be attributed to other diseases; for diagnosis, blood tests and a bone marrow examination are required.

Some other related symptoms

* Fever, chills, night sweats and other flu-like symptoms

* Weakness and fatigue

* Loss of appetite and/or weight

* Swollen or bleeding gums

* Excess bleeding (from a minor cut)

* Neurological symptoms (headache)

* Enlarged liver and spleen

* Easy bruising

* Frequent infection

* Bone pain

* Joint pain

* Swollen tonsils

The word leukemia, which means 'white blood,' is derived from the disease's namesake high white blood cell counts that most leukemia patients have before treatment. The high number of white blood cells are apparent when a blood sample is viewed under a microscope. Frequently, these extra white blood cells are immature or dysfunctional. The excessive number of cells can also interfere with the normal function of other cells.

Some leukemia patients do not have high white blood cell counts visible during a regular blood count. This less-common condition is called aleukemia. The bone marrow still contains cancerous white blood cells, and they are disrupting the normal production of blood cells. However, they are staying in the marrow instead of entering the bloodstream, where they would be visible in a blood test. For an aleukemic patient, the white blood cell counts in the bloodstream can be normal or low. Aleukemia can occur in any of the four major types of leukemia, and is particularly common in hairy cell leukemia.

Four major types

Leukemia is a broad term covering a spectrum of diseases.

Leukemia is clinically and pathologically split into its acute and chronic forms.

* Acute leukemia is characterized by the rapid proliferation of immature blood cells. This crowding makes the bone marrow unable to produce healthy blood cells. Acute forms of leukemia can occur in children and young adults. (In fact, it is a more common cause of death for children in the US than any other type of malignant disease). Immediate treatment is required in acute leukemias due to the rapid progression and accumulation of the malignant cells, which then spill over into the bloodstream and spread to other organs of the body. However, CNS involvement is uncommon, though the disease occasionally causes cranial nerve palsies.

* Chronic leukemia is distinguished by the excessive build up of relatively mature, but still abnormal, blood cells. Typically taking months to years to progress, the cells are produced at a much higher rate than normal cells, resulting in many abnormal white blood cells in the blood. Chronic leukemia mostly occurs in older people, but can theoretically occur in any age group. Whereas acute leukemia must be treated immediately, chronic forms are sometimes monitored for some time before treatment to ensure maximum effectiveness of therapy.

Furthermore, the diseases are classified according to the type of abnormal cell found most in the blood (lymphoid cells vs. myeloid cells).

Combining these two classifications provides a total of four main categories:

	Acute	Chronic
lymphocytic leukemia	Acute lymphocytic leukemia (also known as Acute Lymphoblastic Leukemia, or ALL) is the most common type of leukemia in young children. This disease also affects adults, especially those age 65 and older.	Chronic lymphocytic leukemia (CLL) most often affects adults over the age of 55. It sometimes occurs in younger adults, but it almost never affects children.
myelogenous leukemia (or "myeloid")	Acute myelogenous leukemia (also known as Acute Myeloid Leukemia, or AML) occurs more commonly in adults than in children. This type of leukemia was previously called "acute nonlymphocytic leukemia".	Chronic myelogenous leukemia (CML) occurs mainly in adults. A very small number of children also develop this disease.

Causes and risk factors

There is no single known cause for all of the different types of leukemia. The different leukemias likely have different causes, and very little is certain about what causes them. Researchers have strong suspicions about four possible causes:

* natural or artificial ionizing radiation

* certain kinds of chemicals

* some viruses

* genetic predispositions

Leukemia, like other cancers, result from somatic mutations in the DNA which activate oncogenes or deactivate tumor suppressor genes, and disrupt the regulation of cell death, differentiation or division. These mutations may occur spontaneously or as a result of exposure to radiation or carcinogenic substances and are likely to be influenced by genetic factors. Cohort and case-control studies have linked exposure to petrochemicals, such as benzene, and hair dyes to the development of some forms of leukemia.

Viruses have also been linked to some forms of leukemia. For example, certain cases of ALL are associated with viral infections by either the human immunodeficiency virus (HIV, responsible for AIDS)[citation needed] or human T-lymphotropic virus (HTLV-1 and -2, causing adult T-cell leukemia/lymphoma).

Fanconi anemia is also a risk factor for developing acute myelogenous leukemia.

Until the cause or causes of leukemia are found, there is no way to prevent the disease. Even when the causes become known, they may prove to be things which are not readily controllable, such as naturally occurring background radiation, and therefore not especially helpful for prevention purposes.

Treatment options for leukemia by type

Acute Myelogenous Leukemia (AML)

It is most common for adults; more men than women are affected. Many different chemotherapeutic plans are available for the treatment of AML. Overall, the strategy is to control bone marrow and systemic (whole-body) disease while offering specific treatment for the central nervous system (CNS), if involved. In general, most oncologists rely on combinations of drugs for the initial, induction phase of chemotherapy. Such combination chemotherapy usually offers the benefits of early remission (lessening of the disease) and a lower risk of disease resistance. Consolidation or "maintenance" treatments may be given to prevent disease recurrence once remission has been achieved. Consolidation treatment often entails a repetition of induction chemotherapy or the intensification chemotherapy with added drugs. By contrast, maintenance treatment involves drug doses that are lower than those administered during the induction phase.

In addition, specific treatment plans may be used, depending on the type of leukemia that has been diagnosed. Whatever the plan, it is important for the patient to understand the treatment that is being given and the decision-making process behind the choice.

Initial treatment of AML

Initial treatment of AML usually begins with induction chemotherapy using a combination of drugs such as daunorubicin (DNR), cytarabine (ara-C), idarubicin, thioguanine, etoposide, or mitoxantrone, anabolic steroids.

Research

In 2006, a study performed at the University of Florida showed that açaí fractions containing polyphenolics could reduce proliferation of HL-60 leukemia cells in vitro. This was most likely due to increased rapid cell death (apoptosis) as fractions were also found to activate caspase-3 (an enzyme important in apoptosis) which was inversely correlated to cell death. (Pozo-Insfran et al., 2006). This is a very preliminary study, but indicates a need for more research on the possible anti-cancer effects of açaí.

Follow-up therapy for such patients may involve:

supportive care, such as intravenous nutrition and treatment with oral antibiotics (e.g., ofloxacin, rifampin), especially in patients who have prolonged granulocytopenia; that is too few mature granulocytes (neutrophils), the bacteria-destroying white blood cells that contain small particles, or granules (< 100 granulocytes per cubic millimeter for 2 weeks)

* injection with colony-stimulating factors such as granulocyte colony-stimulating factor (G-CSF), which may help to shorten the period of granulocytopenia that results from induction therapy

* transfusions with red blood cells and platelets

Patients with newly diagnosed disease also may be considered for stem cell transplantation (SCT), either from the bone marrow or other sources. Allogeneic bone marrow transplant (alloBMT) is reserved primarily for patients under 55 years of age who have a compatible family donor. Approximately half of newly diagnosed AML patients are in this age group, with 75% achieving a complete remission (CR) after induction and consolidation therapy. Allogeneic bone marrow transplant is available for about 15% of all patients with AML. Unfortunately, it is estimated that only 7% of all AML patients will be cured using this procedure.

Cont...

Associate Links -

Cancer Support

comprehensive information about specific types of cancer, updates on cancer treatments and news about research advances etc...

Causes and risk factors

Associate Links -

Menu

Type of cancer

Diet and cancer