Observational study on the systematic documentation of disease progression and treatment in end-stage CML (blast crisis)

Chronic myeloid leukemia (CML) is a type of blood cancer in which immature precursor cells of white blood cells (blasts) multiply uncontrollably. The Philadelphia chromosome, which is a genetic alteration, is usually detectable in this disease. In this case, the disease is also referred to as BCR-ABL-positive. In the majority of patients, CML is diagnosed in the first stage, the chronic phase, in which fewer than 10% of blasts are detectable in the blood or bone marrow.

Since the introduction of therapy with tyrosine kinase inhibitors, the prognosis for the disease has improved significantly. Nevertheless, in approximately 5% of patients, the disease progresses to the terminal stage—known as blast crisis. At this stage, the proportion of blasts in the blood or bone marrow increases sharply, and serious symptoms (including infections, bleeding, anemia, and fever) may occur. It is associated with a very poor prognosis. Currently, however, there is very little data on the onset, course, and treatment of patients in blast crisis.

This international registry study will track both retrospectively and prospectively the disease course, treatment response, and survival of patients with CML blast crisis. The goal is to better evaluate and optimize treatment strategies over the long term.

Women and men aged 18 and older with CML blast crisis are eligible to participate in this study, regardless of their current line of therapy. The disease must be BCR-ABL-positive.