Equine nasal and paranasal sinus tumours: part 2: a contribution of 28 case reports.

The research article discusses a study done at the Edinburgh Veterinary School, offering clinical and pathological findings from 28 cases of sinonasal tumours in 27 horses and one donkey, and reviewing common signs, diagnostic techniques, sites of origin, and treatment outcomes in equids.

Findings on Different Types of Tumours

• The study examined several types of sinonasal tumours in equids including squamous cell carcinoma, adenocarcinomas, undifferentiated carcinomas, adenomas, fibro-osseous, bone tumours, ameloblastoma, fibroma, fibrosarcoma, undifferentiated sarcoma, melanoma and lymphosarcoma.
• They found that squamous cell carcinoma was the most common type of tumour in this sample.
• The median ages of animals with epithelial tumours and fibro-osseous/bone tumours were 14 and 4 years respectively, indicating a possible relationship between age and the type of tumour developed.

Common Presenting Signs and Diagnostic Techniques

• Unilateral purulent or mucopurulent nasal discharge was observed in 81% of these equid cases while gross facial swellings were recorded in 82% of cases. So, equid handlers may look for these signs as indications of potential sinonasal tumours.
• Epistaxis (nosebleeds) was observed less frequently, in just 23% of cases.
• Radiology and endoscopy were identified to be the most useful techniques for diagnosis in these cases, helping the vets in locating and identifying the sinonasal tumours.

Tumour Origin and Metastases

• Most of the sinonasal tumours originated in the maxillary area (upper jaw or cheek) than in the nasal cavity.
• Spread to other sites within the head was noticed in 14 out of the 15 carcinoma cases, but the spread was significantly lesser (only 2 out of 13) in the remaining tumours.
• Only three sinonasal tumours had lymph node metastases, and no cases observed any distant metastases, indicating that these tumours often remain localized to the area of origin.

Treatment Outcomes

• Regarding the treatment, surgical intervention did not have a high success rate with malignant tumours, with a median survival duration of only six months post-surgery.
• However, in benign cases, surgery was successful in four out of five cases, with no cases of regrowth recorded for a median of four years post-operatively.