Types of Chronic Myeloid Leukemia (CML)

Chronic Myeloid Leukemia (CML) has three phases:

  • Chronic phase
  • Accelerated phase
  • Blast phase

Most patients with CML are diagnosed in the chronic phase of disease, when they have only a small number of immature cells (blasts) in the blood or bone marrow. Often they only find out they have the disease because blood counts were checked and found to be abnormal.

In accelerated and blast phase disease, the number of immature cells increase, and patients typically experience more symptoms.

People with CML have either the Philadelphia chromosome, or the gene made by the Philadelphia chromosome called Bcr-Abl.

When you are diagnosed, your physicians will request testing to find out if you have the Philadelphia chromosome or Bcr-Abl. New, targeted treatments have been developed to treat these chromosomal abnormalities.

About The Philadelphia Chromosome

The Philadelphia chromosome, discovered more than 50 years ago at Penn by Dr. Peter Nowell and colleagues, provided the first evidence that genetic abnormalities were linked to cancer, an observation that we now think is absolutely fundamental to cancer biology as a whole, and not just leukemia. It also changed the way people with CML would be treated, and improved outcomes and life expectancy for those with CML.

The discovery also ushered in the modern period of cytogenetics.

If you have the Philadelphia chromosome, you are likely to receive therapies designed specifically to target the cells with the abnormal Philadelphia chromosome.

Penn Medicine's Center for Personalized Diagnostics (CPD) builds on this legacy and is paving the way for a new era of genomic and therapeutic pathology.

The CPD offers the highest volume of genome testing in the region, with a current volume of more than 1,500 clinical and research samples to date. In clinical cases, disease-associated mutations have been reported in 75% of patient tests revealing results with therapeutic significance.

Learn more about Penn Medicine's Center for Personalized Diagnostics.

About Bcr-Abl

Bcr-Abl is an oncogene, or a gene that has the potential to cause cancer.

If you have the Bcr-Abl gene, you may receive a Bcr-Abl inhibitor as part of your targeted treatment.