Cutaneous mast cell tumors and systemic mastocytosis in a cat

Abstract

A 15 year-old 3.46 kg female spayed domestic shorthair cat was evaluated by the Oncology Service at Cornell University Hospital for Animals for a progressive modular skin disease and inappetance. Approximately one-year prior the cat had developed multiple cutaneous modules on her head, which were diagnosed by fine needle aspirate and cytology as mast cell tumors (MCT). No treatment was chosen and the cat was monitored for clinical signs and progession of cutaneous lesions. Four months after initial diagnosis the cat had clinical signs of anorexia, vomiting and diarrhea, which prompted an abdominal ultrasound. She was diagnosed with inflammatory bowel disease (IBD), which was managed with corticosteroids. At that time her spleen appeared normal. In the year following her initial diagnosis the skin lesions increased in number despite initiation of methyprednisolone injections by the referring veterinarian. She was also treated intermittently with antibiotics for secondary infections of her cutaneous lesions.