Canine conjunctival mast cell tumors: a retrospective study

Area of Science:

• Veterinary Ophthalmology
• Canine Oncology
• Ocular Pathology

Background:

• Conjunctival mast cell tumors (MCTs) are a common ocular neoplasm in dogs.
• Understanding their clinical presentation, treatment outcomes, and recurrence rates is crucial for effective management.

Purpose of the Study:

• To characterize the signalment, clinical findings, treatment modalities, recurrence rates, and outcomes of canine conjunctival MCTs.
• To provide data to guide veterinary professionals in managing this condition.

Main Methods:

• Retrospective analysis of 32 canine cases with conjunctival MCTs from multiple ocular pathology laboratories.
• Data collection included signalment, tumor characteristics, surgical details, histopathology, and follow-up information via questionnaires.

Main Results:

• Thirty-three conjunctival MCTs were identified in 32 dogs, with surgical excision as the primary treatment.
• Incomplete surgical margins were reported in 25 of 30 evaluated tumors.
• Histologic grades included 30% low, 55% intermediate, and 15% high-grade MCTs.
• Of 25 dogs with follow-up, 15 were disease-free long-term, two experienced local recurrence, and none died from MCT-related disease.

Conclusions:

• Surgical excision is the mainstay treatment for canine conjunctival MCTs, though achieving complete margins can be challenging.
• Despite incomplete margins, a majority of dogs achieve a favorable long-term outcome without MCT-related mortality.
• Further research into adjunctive therapies may be beneficial for cases with incomplete margins.