Abstract: Objective To analyze the clinicopathological and immunohistochemical characteristics of pediatric embryonal rhabdomyosarcoma （ERMS） in Xinjiang. Methods In this retrospective study， the clinical data and immunological phenotype of 20 cases of childhood ERMS were analyzed.
ResultsThere were 11 male and 9 female patients with ages ranging from 10 months to 18 years （mean age： 6.4 years）， among which 85.0％ occur in children under the age of 10. There were 5 cases of the Han nationality， 12 cases of the Uyghur nationality and 3 cases of other ethnic nationalities. The primary sites were found in head and neck （10 cases）， extremities （3 cases）， genitourinary system （3 cases）， trunk （2 cases）， lung （1 case） and pelvic （1 case） region. Clinical symptoms varied widely， based on the location of the primary tumor. There was one case of botryoid rhabdomyosarcoma among 20 ERMS. The positive staining rates for Vimentin， Desmin， MyoD1， Myogenin and CD99 were 100.0％， 90.0％， 55.0％， 90.0％ and 50.0％， respectively. Conclusion ERMS was malepredominant and more common among children under 10 years old. It mainly occurs in head and neck region. The clinical manifestation is different depending on the different regions. The incidence of the minority nationality was significantly higher than that of the Han nationality. Morphology and immunohistochemical staining are very useful in the diagnosis of ERMS.