ORLANDOA gene-profiling chip might help identify children with acute
lymphoblastic leukemia (ALL) who are at low risk of relapse and could be spared
intensive therapy, or who are at high risk for treatment-induced acute myeloid
leukemia (AML) and should not be treated with topoisomerase II inhibitors.
In a plenary presentation at the 43rd Annual Meeting of the American Society
of Hematology (abstract 1816), Allen Eng-Juh Yeoh, MD, said that a limited
number of genes determine risk in these two areas, and that this might permit
development of an inexpensive, simple test that could be used in developing
countries as well as in the United States.
Carolyn A. Felix, MD, who introduced Dr. Yeoh’s paper, said that it
"takes gene expression profiling to the next level by defining biologic
variables that affect prognosis." Dr. Felix is associate professor of
pediatrics, Children’s Hospital, Philadelphia.
Dr. Yeoh was presented with an ASH Merit Award for this study, which was
done in the laboratory of John R. Downing, MD, at St. Jude Children’s
Research Hospital, Memphis. Dr. Yeoh is a clinical fellow in the Departments of
Hematology-Oncology and Pathology at St. Jude and assistant professor of
pediatrics, National University of Singapore.
Dr. Yeoh said that the 80% cure rate for pediatric ALL achieved at St. Jude
and other institutions is the result of stratifying patients by leukemia
subtype and tailoring treatment accordingly, but, he added, this requires
extensive laboratory studies.
The approach pioneered by his group opens the possibility that a single test
might replace molecular screening, immunotyping, and related assays, and also
enable the clinician to identify patients with a high risk of relapse and with
a high vulnerability to treatment-induced secondary AML.