Abstract:?Objective?To improve the quality of fluorescence in situ hybridization(FISH)detection of hematological tumor bone marrow samples bycombination of Triton X-100 and paraformaldehyde(PFA)in pretreatment of sample slides.Methods?In routine FISH procedure for the bone marrow specimen slides from 42 patients with hematological tumors, the experimental group added Triton X-100/4% PFA in pretreatment step, and the control group followed the routine steps.The number of cells without hybridization signal and the proportion of positive cells in both experimental group and control group were paired and compared.When the results of experimental group and control group were inconsistent, the accuracy of the myelodysplastic syndrome(MDS)samples was verified by expanding the count range and the accuracy of multiple myeloma(MM)samples was detected and verified by fluorescence immunophenotyping and interphase cytogenetics as a tool for investigation of neoplasms(FICTION).Results?Compared with the control group, the experimental group showed fewer non-specific fluorescence signals in the hybridization area, clean background and clearer probe signals in the nucleus with success rate of 100% in FISH detection.In experimental group, the average of the proportion of the cells without hybridization signal was(4.30±3.30)%, while it was(8.04±5.45)% in control group, and the paired difference between the experimental and control group was(-3.74±4.27)%.In the experimental group the proportion of cells without hybridization signal was signifiantly lower than that in control group(P<0.001).Among the 132 signal sites where the interpretation results of experimental group and control group were consistent, the average ratio of positive cells in experimental group was(82.16±23.89)%, and(77.10±23.56)% in control group.The paired difference between the two groups was(5.06±10.08)%, and the proportion of positive cells in experimental group was significantly higher than that in control group(P<0.001).In the 5 detection sites where the interpretation results of experimental group and control group were inconsistent, the verificaiton results was same as the experimental group.Conclusion?The combined use of Triton X-100/4% PFA could improve the success rate of interphase FISH detection and the detection rate of positive sites in bone marrow samples.