Use of Fluorescence In Situ Hybridization to Detect Minimal Residual Disease in Hematopoietic Stem Cell Assays from Peripheral Blood Stem Cells of 2 Patients with Trisomy 8 Acute Myeloid Leukemia

Fluorescence in situ hybridization (FISH) was used to analyze peripheral blood stem cells (PBSC) and stem cell assays (SCA) derived from them in 2 patients with acute myeloid leukemia (AML) with trisomy 8 as the sole chromosome abnormality prior to undergoing autologous stem cell transplantation. In both cases, the demonstration of cells containing trisomy 8 in the stem cell product led to significant changes in the patients' treatment. In the initial PBSC collections from each patient, trisomy 8 was found in aspirated granulocyte-monocyte (GM) colonies or aspirated GM clusters but not entire cell populations of SCA dish or uncultured PBSC (one patient). FISH analyses for specific cytogenetic abnormalities in hematopoietic stem cell cultures may be a more useful means of assessing the quality of the stem cell product in patients being considered for autologous stem cell transplantation.