Spindle cell rhabdomyosarcoma of the neck with t(6;8) translocation: report of a case and literature review.

Spindle cell rhabdomyosarcoma is an uncommon subtype of embryonal rhabdomyosarcoma. Found almost exclusively in children, these tumors are classically located in the paratesticular and head and neck regions. Morphologically these lesions can resemble several other benign or malignant soft-tissue spindle cell lesions, especially smooth muscle or myofibroblastic tumors, and thus immunohistochemical staining is often needed to prove skeletal muscle differentiation. Although there is extensive literature reporting the genetics of embryonal rhabdomyosarcoma, little is reported specific to the spindle cell subtype. Below we present the case of a 7-month-old male presenting with a large posterior neck mass that was diagnosed as spindle cell rhabdomyosarcoma. Karyotype evaluation revealed a t(6;8) (p12;q11.2) chromosomal translocation within the lesion. We review the histologic and immunohistochemical diagnosis of these tumors and discuss the genetics of rhabdomyoscarcomas.