DESMIN IS A SPECIFIC MARKER FOR RHABDOMYOSARCOMAS OF HUMAN AND RAT ORIGIN

  • 1 January 1985
    • journal article
    • research article
    • Vol. 118  (1) , 85-95
Abstract
Putative human rhabdomyosarcoma (RMS) has been divided into 2 groups according to desmin content. Tumors (25) with histologic features consistent with but not necessarily sufficient to prove a diagnosis of RMS were desmin-positive. More than 95% of the tumor cells were desmin-positive, suggesting a muscle origin and supporting the diagnosis of RMS. Nine tumors for which the preferred first histologic diagnosis was also RMS were desmin-negative. Reexamination of the original histologic slides together with results from intermediate filament typing resulted in a diagnosis other than RMS for all tumors in this 2nd group, and in several instances other tests were used to prove the correctness of the final diagnosis. The results on human material were extended to a rat model system in which RMA was induced by nickel sulfide. All 24 tumors tested were desmin-positive. Vimentin was coexpressed in a varying percentage of tumor cells in RMS of human and rat origin. Desmin is an excellent marker for rhabdomyosarcoma, yielding few if any false-psitive or false-negative results in frozen or alcohol-fixed material.