Mast cell tumours are the most common malignant skin tumour in dogs, with welfare outcomes ranging from complete cure to end-stage disease depending on grade and management.
Mast cell tumour welfare is complex because the same diagnosis can range from a condition fully curable by surgery to a rapidly fatal systemic disease. The welfare challenge is matching the intensity of investigation and treatment to the individual tumour's behaviour. Over-treating a low-grade tumour causes unnecessary welfare compromise from surgery and chemotherapy, while under-treating a high-grade tumour allows preventable disease progression and suffering. Histopathological grading is essential to guide welfare-proportionate management. Dogs with systemic signs from mast cell tumours require supportive care including H1 and H2 antihistamines and proton pump inhibitors to protect against gastrointestinal welfare compromise.