Chronic myelogenous leukemia (CML) is known as a myeloproliferative disorder—that is, it is a disease in which bone marrow cells proliferate (multiply) outside of the bone marrow tissue.
CML is easy to diagnose, since it has a genetic peculiarity, or marker, that is readily identifiable under a microscope. About 95% of CML patients have a genetic translocation between chromosomes 9 and 22 in their leukemic cells. This abnormality, which is known as the Philadelphia chromosome (Ph1), is named after the city in which it was discovered. The Philadelphia chromosome causes uncontrolled reproduction and proliferation of all types of white blood cells and platelets (blood clotting factors). Sadly, CML is not yet curable by standard methods of chemotherapy or immunotherapy.
CML tends to occur in middle- and retirement-aged people (the median age is 67 years). It occasionally affects people in their 20s, but it is rare in the very young; only 2% to 3% of childhood leukemias are CML. Early disease often is without symptoms (asymptomatic) and is discovered accidentally. Individuals with more advanced cases of CML may appear sickly and experience fevers, easy bruising, and bone pain. Laboratory and physical findings include enlarged spleen (splenomegaly), a high white blood cell count, and absent or low amounts of the white blood cell enzyme alkaline phosphatase.
Like other forms of leukemia, CML is not "staged". Rather, this unstable disease is categorized according to the three phases of its development: chronic, accelerated, and blast.
Chronic phase—Patients in this initial phase have fewer than 5% blast cells and promyelocytes (immature granulocytes) in their blood and bone marrow. This phase is marked by increasing overproduction of granulocytes. Individuals generally experience only mild symptoms, and they respond well to conventional treatment.
Accelerated phase—Patients in this progressive phase have more than 5%, but fewer than 30% blast cells. Their leukemic cells exhibit more chromosomal abnormalities besides the Philadelphia chromosome, and so more abnormal cells are produced. Noticeable symptoms such as fever, poor appetite, weight loss occur, and patients may not respond as well to therapy.
Blast phase (acute phase, blast crisis)—Patients in this final phase have more than 30% blast cells in their blood and bone marrow samples. The blast cells frequently invade other tissues and organs outside of the bone marrow. During this phase, the disease transforms into an aggressive, acute leukemia (70% acute myelogenous leukemia, 30% acute lymphocytic leukemia). If untreated, CML is fatal in roughly 20% of all patients each year.
And a hickman port is an IV catheter used to administer chemo