As the abnormal cells multiply in the bone marrow, they continue to develop additional chromosomal abnormalities. This decreases the capability of the abnormal cells to mature. At this stage, all of the organs of the body are invaded by these blasts, the circulating count can reach several hundred thousand blasts per cubic millimeter. This process usually evolves in a median of four years. CML is a malignancy of the blood forming cells, characterized by excessive proliferation of a single myeloid cell line and their progenitors.
Some patients develop a transient accelerated phase before the development of overt blast crisis.
Median survival from diagnosis is approximately four years. Although some patients may have a prolonged course, CML is a universally fatal disease with conventional therapy. It is capable of producing longterm disease-free survival. Currently twenty to thirty percent of cases of leukemia are attributable to smoking. J.B. Lippincott Co., 1993.