中文摘要：

目的 报道1例伴有t（12;22）（p13;q11）的急性单核细胞白血病病例,并探讨其临床和实验室特点.方法 R显带技术对患者进行染色体核型分析,荧光原位杂交技术检测ETV6基因断裂,反转录PCR检测ETV6-MN1融合基因表达及耐药相关基因GSTP1、MVP和MDR的表达.结果 患者染色体核型为47,XX,＋8,t（12;22）（p13;q11）[10];ETV6基因发生断裂,具有ETV6-MN1融合基因转录本,并经测序证实;表达耐药相关基因GSTP1和MDR.患者对标准的IA方案不敏感,给予CAG方案（阿柔比星剂量提高到每天7 mg/m^2×14d）治疗,经1个疗程再诱导化疗即达到缓解,没有出现严重并发症.结论 t（12;22） （p13;q11）是一种罕见的再现性染色体异常,该易位可产生ETV6-MN1融合基因转录本,伴有该异常的患者对标准的诱导化疗耐药,预后欠佳.

英文摘要：

Objective To report the clinical and laboratory characteristics of a case of acute monocytic leukemia with t（12;22）（p13;q1 1）.Methods R-banding was applied to analyze the karyotype.The rearrangement of ETV6 was detected by fluorescence in situ hybridyzation （FISH）,and the expression of ETV6-MN1 fusion gene was detected using RT-PCR.The PCR products were directly sequenced.Genes related to multi-drug resistance such as GSTP1,MVP and MDR were also detected by RT-PCR.Results The result of R-banding revealed a karyotype of 47,XX,＋8,t（12;22）（p13;q1 1）[10].FISH results showed that one allele of ETV6 was disrupted.ETV6-MN1 was detected by RT-PCR,which was further confirmed by direct sequencing.Expression of GSTP1 and MDR was detected also by RT-PCR.The patient was not sensitive to IA regimen,and then treated with CAG regimen （aclacinomycin total dose increased to 7 mg/m2 × 14 d）.After a course of induction chemotherapy,complete remission was achieved without serious complications.Conclusions t（12;22）（p13;q11） is a rare chromosome abnormality related to acute myelocytic leukemia,resulting in the formation of the EVT6-MN1 fusion gene.Patients with this anomaly always showed chemoresistance and poor prognosis.