Multiple skin tumours in a Doberman Pinscher with colour dilution alopecia

An 11-year-old Doberman Pinscher with clinical and histological skin features consistent with colour dilution alopecia had a long history of skin disease. The animal had hundreds of papules affecting the 'blue' haired areas of the hair coat. The predominant skin lesions included keratinizing infundibular cysts, keratin horns, perifollicular dermatitis, and sebaceous hyperplasia; these lesions were often accompanied by furunculosis and suppurative panniculitis. Over a 9-month period, 32 lesions were examined histologically, which included two lipomas, one infiltrative lipoma, one squamous papilloma, two mast cell tumours, four cavernous haemangiomas, one haemangiosarcoma, and three melanomas. It is unknown at present whether the colour dilution phenotype confers increased risk for tumours of the skin and or subcutaneous tissues.