This report describes a case of a gingival vascular tumor in a 12 year old male castrated Silky Terrier dog. The mass, located above the right maxillary canine tooth, was pedunculated and ranged in color from red to black. It was fast growing and was removed by his regular veterinarian. Histopathology from an outside laboratory reported a hemangiosarcoma with incomplete margins, at which time the dog was referred to Cornell University Hospital for Animals Oncology Service for staging and discussion of therapeutic options. After diagnostics revealed no evidence of metastasis, a central maxilectomy and mandibular lymph node biopsy were performed. No neoplastic cells were found on histopathology. The original tissue removed was obtained and reviewed by pathologists at Cornell as a hemangioma. A review of common oral tumors in dogs is provided, as well as a brief review of vascular tumors. Discrepancies between first-opinion and second-opinion histology are discussed.