耳部原发性横纹肌肉瘤的临床与病理特征

目的 探讨耳部原发性横纹肌肉瘤的临床及病理特征及其与婴儿横纹肌纤维肉瘤、原始神经外胚瘤、恶性横纹肌样瘤等肿瘤的鉴别诊断。方法 用光学显微镜和免疫组织化学以及肉眼观察8例耳部原发性横纹肌肉瘤的临床病理学特征。结果 8例中男性7例，女性1例，平均年龄7．4岁，其中胚胎性横纹肌肉瘤7例，葡萄型横纹肌肉瘤1例。免疫组织化学检查阳性率分别为：Vimentin及Myoglobin100％，Desmin75％，Actin82％。结论 耳部原发性横纹肌肉瘤和其他部位的软组织横纹肌肉瘤相比，组织学上并无特殊，但临床及病理形态学诊断却较困难，常需免疫组织化学标记帮助方能确诊。

Clinicopathological analysis of primary rhabdomyosarcoma of the ear

Objective To investigate the clinicopathological change in primary rhabdomyosarcoma of the ear, and its differential diagnosis with infantile rhabdomyosarcoma, primary neuro-ectodermoma, and malignant rhabdomyoma. Methods Gross and microscopic examination and immunohistochemical staining were performed in 8 cases of primary rhabdomyosarcoma of ear. Results Seven male and one female patients with mean age of 7.4 years were found. The tumor was diagnosed as embryonal rhabdomyosarcoma in 7 patients, and botryoid rhabdomyosarcoma in 1 patient. Immunostaining revealed that vimentin and myoglobin were 100% positive, desmin in 75% and actin in 82%. Conclusions Although the histological appearance of primary ear rhabdomyosarcoma does not differ from those found in other soft tissues, its clinicopathological diagnosis may be difficult in some cases, and further immunohistochemical analyses, may be necessary for a correct diagnosis. Its differential diagnosis includes infantile rhabdomyofibrosarcoma, primary neuroectodermal tumor and malignant rhabdoid tumor.