Granular cell myoblastoma in the tongue of a dog: a case report

A granular cell myoblastoma was found in the dorsal side of the tongue of a 9-year-old female mongrel Pinscher. Macroscopically the tumour was white, well circumscribed, and 1½> cm in diameter. Microscopically the tumour cells were arranged in small compact nests or cords with delicate, poorly vascularized collagen bundles in between. A cinar structures were found, also a few mitotic figures were present. Cytoplasmic granules showed a positive periodic acid Schiff reaction. Ultrastructural features included indented nuclei and small-sized vesicular cytoplasmic granules. The histogenesis of the neoplasm remains uncertain.