The MDS Beacon™

Myelodysplastic syndromes (MDS) patients with del-5q mutation enjoy a high survival rate but are as susceptible to acute myeloid leukemia (AML) transformation as other MDS sub-types, according to a tracking study conducted by European researchers. The findings were presented at the 51st annual American Society of Hematology (ASH) meeting and exposition held in New Orleans at the beginning of December.

The del-5q mutation is a chromosomal abnormality which is characterized by a missing ‘q’ arm of chromosome 5. Although the del-5q sub-type was identified as a specific MDS diagnosis in 2001, few studies have examined the progression of this disease sub-type to AML.  

This study tracked 303 low or intermediate-1 patients with del-5q mutation. The median age of the study participants was 65 years. Patients were identified through MDS registries and followed from diagnosis. The median follow-up time was three years. During the study period, all patients were treated with supportive care. Researchers recorded any changes regarding blood cell count, dependence on red blood cell transfusions, and general disease progression, with progression to AML defined as producing more than 20 percent blasts in the bone marrow. 

Results of the study showed a median survival of nearly six years (71.5 months).  Based on the WPSS score, the median patient survival times were 107 months for very low-risk MDS, 73 months for low-risk MDS, 56 months for intermediate-risk MDS, and 37 months for high-risk MDS.

Del-5q patients with only one chromosomal abnormality achieved median 73 month survival, compared to median survival of 19.3 months for those with more than one chromosomal abnormality. 

The study also revealed that transfusion-independent patients had a significantly higher median survival time (97 months) than transfusion-dependent patients (37 months).

Out of the 303 patients, 44 (15 percent) progressed to AML. Researchers found that patients with intermediate 1 IPSS and high-risk WPSS scores had an increased risk of AML transformation.

In addition, risk for disease progression increased with greater than 5 percent blasts in the bone marrow and red blood-cell transfusion dependence. 

Researchers concluded that the survival of del-5q patients is high.  When compared to other MDS sub-types or diagnoses, del-5q patients were found to have a risk for AML progression comparable with patients who have refractory cytopenia with multilineage dysplasia without the del-5q mutation.

Researchers recommended that further studies be conducted to better identify MDS patients at greatest risk for AML progression.

For more information, see abstract 945 on the 2009 ASH meeting Web site.