[Comparison of conventional cytogenetics and interphase fluorescence in situ hybridization in diagnosis of acute promyelocytic leukemia]. 
The aim of this study was to explore cytogenetic characteristics of acute promyelocytic leukemia (APL) and compare the interphase fluorescence in situ hybridization (I-FISH) with conventional cytogenetic (CC) analysis.  A total number of 157 APL patients were recruited in this study, and the I-FISH and CC were applied to analyze cytogenetic features.  Chromosome samples of bone marrow cells were prepared by short-term culture.  Out of all 157 cases, 136 were observed with CC assay, 66 with I-FISH, of which 45 samples were analyzed with both methods.  The results showed that among all 136 CC samples, t(15;17)(q22;q21) was found in 120 cases, of which 107 cases was isolated t(15;17)(q22;q21) abnormality, 13 cases was complex abnormalities and 12 case without mitotic figure.  Among all 66 cases of I-FISH group, PMI/RARα fusion gene was found in 64 cases (97.0%), suggesting that I-FISH group was more sensitive than CC group (p = 0.041).  It is concluded that combination of I-FISH and CC techniques plays a pivotal role for diagnosis and detection of minimal residual disease in APL.