Overview
Mast cell tumors (MCTs) arise from mast cells in the skin and can range from benign lumps to aggressive cancers. They’re deceptive — they can look like any skin bump and change size rapidly due to histamine release. Any new skin lump on a dog should be checked by a vet. Treatment depends on grade: low-grade tumors are cured by surgery alone, while high-grade tumors require chemotherapy.
Symptoms to Watch For
- New skin lump that changes size (swells and shrinks)
- Redness and irritation around the lump
- Vomiting or loss of appetite (from histamine release)
- Bruising easily near the tumor
- Multiple skin lumps
How Nutrition Helps
While diet cannot prevent mast cell tumors, nutritional support during treatment improves outcomes. Omega-3 fatty acids reduce inflammation and may have anti-tumor effects. Antioxidants support the immune system during chemotherapy. Maintaining calorie intake and body condition during treatment is critical for recovery.
How Activity Helps
Maintain normal activity levels. Post-surgery, follow your vet’s instructions for restricting activity during wound healing.
Prevention Tips
- Check your dog’s skin monthly for new lumps
- Have any new lump aspirated by your vet — don’t wait
- Don’t squeeze or irritate skin lumps (releases histamine)
- Early surgical removal gives the best prognosis
- Regular vet checkups with full body skin exam
Breeds at Higher Risk
Boxers, Boston Terriers, Labrador Retrievers, Beagles, Shar Peis, Bulldogs, and Pugs.
Breeds more commonly affected
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