Translocation (6;9)- Related Myeloid Neoplasms in Children Are Diseases of Older Children with Variable Presentations.
John Joseph, Andrea Sheehan, Xinyan Lu, Tarek Elghetany. Baylor College of Medicine, Houston, TX; Texas Children's Hospital, Houston
Background: Translocation (6;9) is recognized in the current WHO Classification as acute myeloid leukemia with recurrent cytogenetic abnormalities. Patients tend to have a poor outcome.
Design: We reviewed the cytogenetics records at Texas Children's Hospital in the last 6 years. Four cases of t(6;9) was found among 92 cases of myeloid neoplasms for a frequency of 4%. Clinical follow-up was obtained by review of each patient's electronic medical record.
Results: In three cases, t(6;9) was the sole abnormality while one patient had concomitant complex abnormalities. The age of all four children ranged from 12-15 years. There were three males and one female. Two cases presented with a sufficiently high blast count to be labeled as acute myeloid leukemia. One case had Auer rods and 10% blasts in the bone marrow and the diagnosis of RAEB-2 was rendered. The fourth case presented with a high white cell count and marked dysplastic features but less than 20% blasts in the peripheral blood and bone marrow prompting the diagnosis of atypical CML. The two AML cases went into remission with standard induction therapy followed by matched related donor transplant. Both patients are alive with no disease 1 and 2.5 years after diagnosis. The RAEB-2 patient received allogeneic BMT and is alive and well 4 years after diagnosis. The atypical CML case died in three weeks of brain hemorrhage secondary to a rapidly progressive DIC. This patient had complex cytogenetic abnormalities at presentation.
Conclusions: Despite this limited study, we may conclude that t(6;9) myeloid disorders affect older children, may have a variety of presentations, including MDS, AML, and atypical CML and they respond well to therapy if the t(6;9) is the sole cytogenetic abnormality.
Monday, February 28, 2011 1:00 PM
Poster Session II # 173, Monday Afternoon