Fibrosarcoma in the labial commisure of a dog: Case Report

Abstract

Fibrosarcoma is a malignant mesenchymal tumor classified as the third most common oral tumor in dogs. It is a locally aggressive and invasive neoplasm, with a low metastasis rate if identified early. The recommended treatment is total resection with a safety margin in order to avoid recurrence, as it is common with this oral tumor. The present work aims to report a case of this condition in a mixed breed canine, nine years old, who had significant periodontal disease, gingival bleeding, and an increase in volume on the inner side of the right labial commissure. The tumor appeared as a firm and rounded lump, with signs of inflammation. Cytology was performed for diagnostic purposes, which was compatible with mesenchymal neoplasia. Thus, total surgical resection was performed as treatment, with adequate margins, associated with reconstructive surgery due to lack of sufficient tissue to achieve suture and surgical closure. Histopathological analyses resulted in a tumor process compatible with fibrosarcoma. After follow-up and removal of the stitches, the animal was referred to the veterinary oncologist for further investigation.