Establishment Of Fluorescence In Situ Hybridization In The Detection Of The Number Of Chromosome 8 Anomalies And Bcr / Abl Fusion Gene

Objective To explore the sensitivity and specificity of conventional cytogenetics (CC),nested-reverse transcriptase polymerase chain reaction (nested-RT-PCR) and dual-color and dual-fusion fluorescence in situ hybridization (D-FISH) technique in monitoring the tumor load of chronic myeloid leukemia (CML) during treatment. Methods CC,nested-RT-PCR and interphase D-FISH were simultaneously carried out to detect the tumor load of 12 CML patients during treatment. Results 24 specimens from 5 CML patients before and after interferon-alpha (IFN-α) therapy were investigated and the results showed that: 23 specimens were Ph(+) with different positive ratio by CC. All specimens were bcr/abl mRNA (+) by RT-PCR. The Ph(-)bcr/abl(+) specimen from case 2 at 75 months post-treatment showed 4.5% bcr/abl(+) cells by FISH. 2 specimens from case 1 at 22 months,26 months post-treatment, 2 specimens from case 5 at 12 months,16 months post-treatment and 2 specimens from case 4 at 6 months,10 months post-treatment with same Ph(+) ratio respectively were investigated by FISH and showed 47.5% and 39.5%,74.0% and 60.5%,99.0% and 99.5% bcr/abl(+) cells respectively.40 specimens from 7 CML patients before and after non-myeloablative allogeneic stem cell transplantation (allo-NST) were analyzed and the results showed that: 29 specimens were Ph(+) with different positive ratio and 3 specimens with lower cells didn't been analyzed by CC. 36 specimens were bcr/abl mRNA (+) by RT-PCR. 4 specimens from case 6 at 12 months,18 months﹑26 months,38 months post- allo-NST were Ph(-) and bcr/abl mRNA (-).4 Ph(-)bcr/abl(+) specimens,2 from case 6 at 9 months,10 months post allo-NST, 1 from case 7 at 15 months post allo-NST, 1 from case 8 at 12 months post allo-NST showed 5.4%,0%,16.5% and 1.5% bcr/abl(+) cells by FISH. 3 specimens with lower cells, 2 from case 10 at 20 days﹑60 days post allo-NST and 1 from case 12 at 40 days post allo-NST were analyzed by FISH and showed 55.0%,27.5% and 73.5% bcr/abl(+) cells. The Ph(-)bcr/abl(-) specimen from case 6 at 12 monthss post- allo-NST showed 0% bcr/abl(+) cells by FISH. Conclusions CC can be used as a basic tool to monitor the change of tumor load in CML during treatment. When specimen with lower cells didn't been analyzed by CC during early post-NST period or result of CC can't evaluate precisely dynamic change of tumor load and when tumor load in patient with treatment were lower to Ph(-) by CC while bcr/abl mRNA (+) by RT-PCR, FISH must be used to detect precisely tumor load and monitor dynamic change of it. More sensitive RT-PCR was used to monitor tumor load when it was lower to bcr/abl(-) by FISH during treatment.