ACUTE MYELOGENOUS LEUKEMIA

Acute myelogenous leukemia, or AML is the most commonly diagnosed type of adult leukemia, and accounts for about half the cases of childhood leukemia. It is specifically a malignancy of the myeloid line of white blood cells. Risks include heredity, radiation, chemical exposure, especially to benzene, and previous treatment with certain drugs (alkylating agents).

Myeloid leukemias are characterized as "acute" or "chronic" based on how quickly they progress if not treated. They can be further characterized morphologically, cytochemically, or by characterization of the underlying chromosomal abnormality. A French-American-British (FAB) classification system groups these into seven different diseases (M0, M1, M2, M3, M4, M5, M6, & M7).

AML is usually diagnosed in adults after a few days of nonspecific symptoms which are due to abnormal blood cell number, such as fatigue, weakness, bruises, small rash-like spots, gum and nose bleeds or infection.

Chemotherapeutic treatment is divided into two phases: induction and postremission therapy. In all FAB subtypes except M3, the usual treatment includes cytarabine and an anthracycline (such as daunorubicin or idarubicin). Complete remission is obtained in about 70 percent of newly diagnosed adults. The bone marrow is examined for malignant cells after each course of treatment: remission can be achieved after one to three courses.

Postremission therapy can include more intensive chemotherapy, or bone marrow transplant.