TEL-AML1 frequency in multi-ethnic Malaysian pediatric acute lymphoblastic leukemia.

Eighty-eight multi-ethnic Malaysian pediatric acute lymphoblastic leukemia (ALL) patients were screened for the TEL-AML1 rearrangement by reverse transcription-polymerase chain reaction (RT-PCR). Fluorescence in situ hybridization (FISH) was used as an independent screen for 30 cases and to confirm RT-PCR positive cases. Seventeen patients, or 19%, were found to be t(12;21) positive. Ethnically the group comprised 12 Malays, 4 Chinese, and 1 Indian. All patients, including 1 with an unusual blast cell morphology who suffered an early relapse and death, were characteristic TEL-AML1 cases in cell count, age, ALL subset classification, and fusion transcript expressed. This study shows that in Malaysia, TEL-AML1 is found in the same distinct ALL subset and at a similar frequency as in other diverse childhood ALL cohorts.