中文摘要：

[目的]探讨横纹肌肉瘤的临床病理学、免疫组化及分子遗传学特征。[方法]回顾性研究22例横纹肌肉瘤（RMS）患者的病历资料、病理形态学特点、免疫组化以及分子遗传学特征。[结果]本组男15例,女7例;年龄2~60岁,中位年龄35岁。肿瘤8例发生于骨盆与躯干;发生于四肢6例;其他部位6例。组织学上：10例为腺泡性横纹肌肉瘤;11例为多形性横纹肌肉瘤;1例表现为胚胎性横纹肌肉瘤形态。免疫组化标记显示：所有病例均不同程度的表达Vimentin（17/17,100%）和Desmin（22/22,100%）;大部分病例表达Myogenin（19/22,86.3%）和MyoD1（15/17,88.2%）,少部分病例表达CD99（5/17,29.4%）及CK（3/17,17.6%）,17例横纹肌肉瘤LCA均为阴性（0/17,0%）,Ki-67平均阳性指数为43%。FISH结果显示：10例腺泡性横纹肌肉瘤均检测到FKHR基因分离;11例多形性横纹肌肉瘤及1例胚胎性横纹肌肉瘤均未检测到FKHR基因分离信号。[结论]组织学结合免疫组化及FKHR基因FISH检测对横纹肌肉瘤的诊断及分型具有重要意义。

英文摘要：

[Objective] To investigate the clinicopathological,immunohistochemical,and molecular genetic characteristics of rhabdomyosarcoma. [Methods] Twenty-two cases of rhabdomyosarcoma were reviewed to determine their clinicopathological,morphological,immunohistochemical,and molecular genetic features. [Results] The patient cohort comprised 15 male and 7 female patients,aged 2 to 60 years（ median： 35 years）. Of the 22 tumors,8 were in the pelvis and trunk,6 were in the extremities,and 6 were in other sites. Histologically,10 tumors were alveolar rhabdomyosarcomas,11 were pleomorphic rhabdomyosarcomas,and 1 was an embryonic rhabdomyosarcoma. On immunohistochemistry,all tumor cells were diffusely positive for vimentin（ 17 /17,100%） and desmin（ 22 /22,100%）,whereas the tumors showed variable expression of myogenin（ 19 /22,86. 3%）,myoD1（ 15 /17,88. 2%）,CD99（ 5 /17,29. 4%）,and cytokeratin（ 3 /17,17. 6%）. Leucocyte common antigen expression was negative in all 17 cases analyzed（ 0 /17,0%）. The average Ki-67 index was 43%. Fluorescence in situ hybridization（ FISH） results revealed the FKHR gene rearrangement in 10 cases of alveolar rhabdomyosarcoma,whereas 11 cases of pleomorphic rhabdomyosarcoma and 1 case of embryonic rhabdomyosarcoma were negative for the FKHR gene rearrangement.[Conclusion] Histological examination combined with immunohistochemistry and FISH play an important role in the differential diagnosis of rhabdomyosarcoma.