儿童横纹肌肉瘤的病理学研究

目的探讨儿童横纹肌肉瘤的病理形态学特点。方法复习和分析30例儿童横纹肌肉瘤的形态学和免疫组织化学染色结果。结果30例横纹肌肉瘤患儿中，男性22例，女性8例。组织学类型包括胚胎性（20／30，66．67％）、腺泡状（8／30，26．67％）和梭形／硬化性（2／30，6．67％）横纹肌肉瘤3种。发生部位依次为躯干（15／30，50．00％）、头颈（7／30，23．33％）、四肢（6／30，20．00％）和泌尿生殖系统（2／30，6．67％）。免疫组织化学染色示肌特异性肌动蛋白（MSA）、平滑肌肌动蛋白（SMA）、结蛋白（DES）、肌细胞生成素（MyoG）和肌调节蛋白（NyoDl）均有不同程度的阳性表达。结论胚胎性、腺泡状和梭形／硬化性横纹肌肉瘤是儿童横纹肌肉瘤的主要类型，组织学上主要表现为原始的小圆细胞，部分病例可见横纹肌母细胞。肿瘤细胞不同程度表达NSA、SMA、DES、MyoG和MyoDl等肌源性标志物。鉴别诊断主要包括神经母细胞瘤、外周原始神经外胚层肿瘤等。

Pathological study of childhood rhabdomyosarcoma

Objective To study the pathologic characteristics of childhood rhabdomyosarcoma. Methods Thirty cases of pediatric rhabdomyosareoma were reviewed by histological and immunohistochemical observation. Results There were 22 boys and 8 girls. Histologically, all the cases were divided into embryonal, alveolar, and spindle/sclerosing rhabdomyosarcoma types, in which, embryonal type accounted for 66.67% （20/30）; alveolar type, 26.67% （8/30）; and spindle/sclerosing type, 6. 67% （2/30）. The location of the tumors included the trunk （50%, 15/30）, head and neck （23.33%, 7/30）, extremities （20%, 6/30）, and urinary system （6.67%, 2/30）. Immunohistochemical staining findings indicated that muscle-specific actin （MSA）, smooth muscle actin （ SMA）, Desmin, myogenin （ MyoG）, and MyoD-1 had different degrees of positive expression. Conclusion Embryonal, alveolar, and spindle cell/sclerosing rhabdomyosarcoma are main histological types of rhabdomyosarcoma of children. They mainly show primitive small round cells with rhabdomyoblast cells in some cases. Tumor ceils express different levels of muscle origin marks such as MSA, SMA, Desmin, MyoG, and MyoD-1. Differential diagnosis should be made with neuroblastoma and peripheral primitive neural ectoderm tumor.