Abstract: ObjectiveTo optimize pre-coated multiple-probe fluorescencein situ hybridization (FISH) to improve its efficiency
in cytogenetic diagnosis of acute leukemia. MethodsThe original multiple-probe FISH techniques were optimized by
adjusting the cell density and adding a process of protease digestion. Cytogenetic anomalies were detected in141patients with
acute lymphocytic leukemia (ALL) or acute myeloid leukemia/ myelodysplastic syndromes (AML/MDS) using the modified
technique, and 35of the patients were also examined using the original technique. The successful detection rate and positive
site detection rate were compared between the modified and original techniques. ResultsModification of the pre-coated
multiple-probe FISH technique resulted in an significant increase of the successful detection rate (from85.3% to100%) and the
positive site detection rate (from5.1% to8.6% ) in ALL patients; in AML/MDS patients, the successful detection rate was
significantly improved from67.4% to99.8% and the positive site detection rate from3.5% to6.0% (P<0.01). ConclusionThe
modified pre-coated multiple-probe FISH technique can significantly increase the diagnostic efficiency of cytogenetic
abnormalities in leukemic patients.