dic(7;9)(p11.1;p11.1) and del(7)(q36) as a Primary Abnormality in Childhood B-cell Precursor ALL: A Case Report.

OBJECTIVES: B-cell acute lymphoblastic leukemia is the clonal proliferation of B-lymphoblasts, primarily in the blood and bone marrow. The morphology of these cells is largely of L1 or L2 type according to French-American-British (FAB) classification. Molecular cytogenetic testing remains the gold standard technique for genetic classification of ALL along with molecular tests. Here we describe a case of pediatric B-ALL with dic(7;9)(p11.1;p11.1) and deletion of CUL1 (7q36) as a primary abnormality. Although both 7p and 9p deletions are associated with poor prognosis, the patient responded well to standard risk induction therapy. The abnormalities were identified by conventional karyotype and fluorescence in situ hybridization. Response to treatment was assessed by monitoring minimal residual disease.