A case of adult rhabdomyoma in the tonsillar region. A light and electron microscope study.

A case of rhabdomyoma in a 71-year-old woman is reported. The lobulated, soft tumour was situated in the left tonsillar region. It was encapsulated, easily removable and of a uniformly greyish-red colour on the cut surface. Both light and electron microscopy showed the classical features of a benign rhabdomyoma of adult type, with large "spider" cells and typical myofilaments, as well as Z-band fragments. To achieve the correct diagnosis in such cases the most important thing is probably to bear the possibility of this rare, but benign tumour in mind.