A rare case of nasal osteoma in a dog: a case report

A 35-month-old female German shepherd weighing 33.2 kg was referred to our department with a 10-month history of sneezing and left nasal swelling. On clinical examination, the dog showed deformity of the left nasal plane in the absence of any cutaneous lesions or nasal discharge, and presented with nasal snoring noises during both the inspiratory and expiratory phases. The patency of nasal cavities was evaluated using the cotton swab test, and was found to be preserved only on the right side. Endoscopic, radiographic and computed tomographic examination revealed an osteoproductive lesion that distorted the nasal, maxillar and frontal bones, completely occupying the left nasal cavity and frontal sinuses, resulting in destruction of the nasal septum and invasion of the contralateral nasal cavity. Five bioptic samples of the mass were collected from the cutaneous surface using a 9G Jamshidi bone marrow bioptic instrument. Histologically, the lesion consisted of a non-encapsulated, multilobulated mass composed of dense coalescing trabeculae of well-differentiated bone, which was lined by osteogenic cells. The morphology was suggestive of nasal osteoma. Due to the large size of the mass, evidenced by computed tomography, chronic systemic nonsteroidal anti-inflammatory treatment with carprofen was proposed instead of surgery. The description of this case is useful for veterinarians, who should consider osteoma as a possible differential diagnosis for nasal tumours.