Spontaneous differentiated squamous cell carcinoma of cheek pouch in a Syrian hamster

A 2-year-old male hamster was presented because of left facial swelling and salivation. Necropsy was performed and affected cheek pouch with tissue samples of regional and internal organs were submitted for histopathological study. In histopathological examination it was found that the tumor consisted of cords and islands of tumoric epithelial cells which were diffused in the dermis. Vacoulation of cytoplasm in many cells were striking features. The lesion was infiltrated by mononuclear cells. These findings were consistent with differentiated squamous cell carcinoma, which restricted only to the left cheek pouch. There was no evidence of tumoral invasion to the other organs. Cheek pouch spontaneous tumors in hamsters have been rarely reported.