Rib metastases from a non-tonsillar squamous cell carcinoma in a dog.

Metastatic spread to the ribs in a 15-year-old, male, neutered, Irish setter is reported occurring secondary to an oral squamous cell carcinoma (SCC). The dog presented with a history of a rapidly growing SCC of the right upper incisive region, which was confirmed by histopathology as a SCC. Thoracic radiographs showed bony lesions associated with the body of the right third rib, and the fifth and seventh costal cartilages. A rostral partial maxillectomy was performed as palliative treatment for the oral mass and a core biopsy of the lesion on the third rib was performed. The rib lesion was identified histopathologically as a metastatic SCC. A review of the literature of oropharyngeal SCC and the metastatic potential of non-tonsillar SCC is presented, in particular metastatic bone disease. This case report suggests possible implications of metastatic bone disease for treatment and prognosis for future cases of non-tonsillar SCC.