leukemia
[loo-ke´me-ah] a progressive, malignant neoplasm of the blood-forming organs, marked by diffuse replacement of the bone marrow development of leukocytes and their precursors in the blood and bone marrow. It is accompanied by a reduced number of erythrocytes and blood platelets, resulting in anemia and increased susceptibility to infection and hemorrhage. Other typical symptoms include fever, pain in the joints and bones, and swelling of the lymph nodes, spleen, and liver. adj.,
adj leuke´mic.
Types of Leukemia. Leukemia is classified clinically in several ways: (1) acute versus chronic, terms that have become altered from their usual meanings and refer to the degree of cell differentiation; (2) the predominant proliferating cells: myelocytic, granulocytic, or lymphocytic; and (3) increase in or maintenance of the number of abnormal cells in the blood—preleukemic.
Acute leukemia is characterized by fatigue, headache, sore throat, and dyspnea, followed by symptoms of acute tonsillitis, stomatitis, bleeding from the mucous membranes of the mouth, alimentary canal, and rectum, and pain in the bones and joints. There eventually is enlargement of the lymph nodes, liver, and spleen. Common to all leukemias are the tendency to bleed and the resultant anemia and increased susceptibility to infection. The diagnosis of leukemia requires confirmation of leukemic cells in the bone marrow by bone marrow biopsy and aspiration. Abnormalities may also be seen in peripheral blood smears.
Treatment. The treatment of choice is systemic combination chemotherapy with a variety of antineoplastic drug regimens. The disease can also be treated by a bone marrow transplant after a remission is achieved with chemotherapy.
Patient Care. Leukemia affects almost every system within the body and can present a variety of patient care problems. Of primary concern are those symptoms attendant to suppression of normal bone marrow function, particularly susceptibility to infection due to the predominance of immature and abnormally functioning white blood cells, bleeding tendency owing to decreased platelet count, and anemia due to decreased erythrocyte count. Chronic abnormal tissue perfusion, increased need for rest, and decreased sensitivity to heat and cold require careful planning and intervention. Additionally, the patient will need relief from pain and discomfort arising from enlargement of the lymph nodes and distention of the liver and spleen.
Because of the malignant nature of leukemia and the fear and anxiety created by the knowledge that one has a form of cancer, patients and their families and significant others will need help in coping with anxiety, mental depression, and realistic fears about dying and death. The financial burden of the illness and disruption of the life of the individual and the family also impose a special burden on them. Referral to appropriate persons and agencies that can help meet their needs is an essential part of the holistic care of the patient with leukemia.
acute lymphoblastic leukemia (ALL) (
acute lymphocytic leukemia)
acute leukemia of the
lymphoblastic type, one of the two major categories of acute leukemia, primarily affecting young children. Symptoms include anemia, fatigue, weight loss, easy bruising, thrombocytopenia, granulocytopenia with bacterial infections, bone pain, lymphadenopathy, hepatosplenomegaly, and sometimes spread to the central nervous system (
meningism) or to other organs. There are three major subtypes: The
pre–B-cell is the most common, consisting of small uniform lymphoblasts that do not synthesize complete functional
immunoglobulins or synthesize heavy chains only. The
B-cell type is rare and consists of lymphoblasts that express surface immunoglobulins and have a surface translocation similar to that of
Burkitt's lymphoma. The
T-cell type has cells that express surface antigens characteristic of T cells.
acute myeloblastic leukemia acute myelogenous leukemia (AML)
acute leukemia of the
myelogenous type, one of the two major categories of acute leukemia; most types affect primarily middle-aged to elderly people. Symptoms include anemia, fatigue, weight loss, easy bruising, thrombocytopenia, and granulocytopenia that leads to persistent bacterial infections. Several types are distinguished, named according to the stage in which abnormal proliferation begins:
acute undifferentiated l., acute myeloblastic l., acute promyelocytic l., acute myelomonocytic l., acute monocytic l., acute erythroleukemia, and
acute megakaryocytic l. Called also
acute myelocytic l. and
acute nonlymphocytic l. acute promyelocytic leukemia acute myelogenous leukemia in which more than half the cells are malignant
promyelocytes, often associated with abnormal bleeding secondary to thrombocytopenia, hypofibrinogenemia, and decreased levels of coagulation factor V; it usually occurs in young adults. Called also
promyelocytic leukemia.
adult T-cell leukemia (adult T-cell leukemia/lymphoma) a form of leukemia with onset in adulthood, leukemic cells with T-cell properties, frequent dermal involvement, lymphadenopathy and hepatosplenomegaly, and a subacute or chronic course; it is associated with human T-cell leukemia-lymphoma virus.
basophilic leukemia a rare type of leukemia in which
basophils predominate; both acute and chronic varieties have been observed.
chronic granulocytic leukemia chronic leukemia of the
myelogenous type, occurring mainly between the age of 25 and 60, usually associated with a unique chromosomal abnormality. The major clinical manifestations of malaise, hepatosplenomegaly, anemia, and leukocytosis are related to abnormal, excessive, unrestrained overgrowth of
granulocytes in the bone marrow. Called also
chronic myelocytic or
chronic myeloid leukemia.
chronic lymphocytic leukemia chronic leukemia of the
lymphoblastic type, a common form mainly seen in the elderly; symptoms include lymphadenopathy, fatigue, renal involvement, and pulmonary leukemic infiltrates. Circulating malignant cells are usually differentiated
B-lymphocytes; a minority of cases have mixed T and B lymphocytes or entirely
T-lymphocytes.
chronic myelomonocytic leukemia a slowly progressing form of
chronic leukemia that usually affects the elderly and sometimes progresses to
acute myelomonocytic leukemia. Symptoms include splenomegaly, monocytosis with granulocytosis, and thrombocytopenia.
leukemia cu´tis leukemia with leukocytic invasion of the skin marked by pink, reddish brown, or purple macules, papules, and tumors.
eosinophilic leukemia a form of leukemia in which the
eosinophil is the predominating cell. Although resembling
chronic granulocytic leukemia in many ways, this form may follow an acute course despite the absence of predominantly blast forms in the peripheral blood.
hairy cell leukemia a form of
chronic leukemia marked by splenomegaly and by an abundance of abnormal large mononuclear cells covered by hairlike villi (hairy
cells) in the bone marrow, spleen, liver, and peripheral blood. Called also
leukemic reticuloendotheliosis.
mast cell leukemia a rare type marked by overwhelming numbers of tissue mast cells in the peripheral blood.
micromyeloblastic leukemia a form of
myelogenous leukemia in which the immature, nucleoli-containing cells are small and are distinguishable from lymphocytes only by special staining.
myelocytic leukemia (
myelogenous leukemia) (
myeloid granulocytic leukemia) a form arising from myeloid tissue in which
polymorphonuclear leukocytes and their precursors predominate.
plasma cell leukemia (
plasmacytic leukemia) a rare type in which the predominating cell in the peripheral blood is the plasma cell; it is often seen in asociation with
multiple myeloma.
prolymphocytic leukemia a type of
chronic leukemia marked by large numbers of circulating lymphocytes, predominantly
prolymphocytes, with massive splenomegaly and occasionally lymphadenopathy; prognosis is often poor.
Rieder cell leukemia a form of
acute myelogenous leukemia in which the blood contains the abnormal cells called
Rieder's lymphocytes, asynchronously developed lymphocytes that have immature cytoplasm and a lobulated, indented, comparatively more mature nucleus.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.