非典型性脂肪瘤性肿瘤/高分化脂肪肉瘤MDM2蛋白表达和基因扩增检测及临床意义

Clinical significance of MDM2 protein expression and gene amplification in atypical lipomatous tumour/well-differentiated liposarcoma

目的探讨非典型性脂肪瘤性肿瘤/高分化脂肪肉瘤(atypical lipomatous tumour/well-differentiated liposarcoma,ALT/WDL)中MDM2蛋白表达和基因扩增,分析MDM2蛋白表达和基因扩增在ALT/WDL中的意义。方法采用免疫组化Eli Vision两步法及荧光原位杂交(fluorescence in situ hybridization,FISH)检测58例ALT/WDL中MDM2蛋白表达及基因扩增状态。结果免疫组化检测显示58例ALT/WDL中MDM2蛋白阳性率为79.3%;FISH法检测MDM2基因扩增率为96.5%。免疫组化和FISH检测结果阳性率差异有统计学意义(P<0.05)。结论 MDM2蛋白表达和MDM2基因扩增为ALT/WDL的诊断提供依据;由于免疫组化检测阳性率接近80%,故在多数没有FISH条件的单位予以开展免疫组化MDM2蛋白检测,可以帮助诊断大多数ALT/WDL病例。

Purpose This study was to investigate the clinical significance of MDM2 protein expression and gene amplifica- tion in atypical lipomatous turnout/well-differentiated liposarcoma （ALT/WDL）. Methods MDM2 protein expression and gene amplification were detected by h＇amunohistochemistry of EliVision two-step method and fluorescence in situ hybridization （ FISH ） in 58 cases of ALT/WDL. Results Immunohisto-chemical staining showed that the positive rate of MDM2 was 79. 3%, MDM2 gene amplification rate by FISH assay was 96. 5%. There was statistically significant differences between immunohistochemistry and FISH （ P 〈 0. 05 ）. Conclusion MDM2 protein expression and MDM2 gene amplification provide the basis for diagnosis of ALT/WDL. However, a positive rate of MDM2 by immunohistochemistry is nearly 80% , so we recom- rnand to carry out immunohistochemical MDM2 protein detection in most conditions without FISH which can help in the diagnosis of most cases of ALT/WDL.