Abdul-Jabbar and Facts About CML

NBA legend Kareem Abdul-Jabbar, 62, has Philadelphia-chromosome-positive (Ph+) chronic myeloid leukemia (CML), according to numerous news sources. ABC News reports that Abdul-Jabbar was diagnosed with the disorder in December of last year. What treatment Jabbar has received to date is unclear; although the LA Times states that the disease is managed with "daily oral medication" (probably imatinib [Gleevec; Novartis]) and regular "blood analysis."

Here are some facts about CML and its treatment, according to the NCCN Clinical Practice Guidelines:

• CML accounts for 15% of adult leukemias. This year, an estimated 5050 cases will be diagnosed, and 470 will die of the disease.
• The median age of onset is 67 years.
• The disease is characterized by a translocation between chromosomes 9 and 22, resulting in the formation of the Philadelphia chromosome. The translocation results in a fusion gene, BCR-ABL, which is believed to play an important role in the development of CML. The fusion protein produced by BCR-ABL is an oncogene, with unregulated tyrosine-kinase (TK) activity.
• CML occurs in 3 phases: chronic, accelerated, and blast. CML is usually diagnosed in the chronic phase.
• Untreated CML will progress to advanced disease in 3-5 years.
• First-line treatment for chronic Ph+ CML is imatinib, a selective inhibitor of the TK portion of the bcr-abl fusion protein. 
• Responses to the initial treatment of CML are monitored periodically (eg, every 3 months), by assessing bone marrow cytogenetics (ie, cytogenic response [CyR]) and transcript numbers of the BCR-ABL gene (ie, molecular response).
• Long-term data (median follow-up, 60 months) for first-line imatinib: complete CyR, 87%; overall survival, 89%.
• The most common high-grade toxicities with imatinib: neutropenia and thrombocytopenia. Rare cardiotoxicity has been reported with long-term therapy.
• The most common adverse events with imatinib: GI disturbances, edema, rash, and musculoskeletal complaints.
• Management of disease progression that occurs during imatinib therapy may include increasing the imatinib dosage; the use of an alternative TK inhibitor (dasatinib [Sprycel; BMS] or nilotinib [Tasigna; Novartis]); hematopoietic stem cell transplantation (HSCT), or enrollment in a clinical trial. Traditional chemotherapy regimens may also be considered for blast crisis.

The NCCN guidelines conclude, "The development of imatinib...has revolutionized the treatment of CML." Before the advent of imatinib, CML was treated medically with interferon alpha and low-dose cytarabine. According to ABC, Abdul-Jabbar is a spokesperson for Novartis, the manufacturer of imatinib. 

The FDA approved imatinib for the first-line treatment of CML in December 2002.

NCCN = National Comprehensive Cancer Network.

Image of Abdul-Jabbar in 2007 from Flickr.