Combined tumour on the prepuce of a 5‐year‐old male neutered mixed breed dog

Abstract A 5‐year‐old, male, neutered, mixed breed dog initially presented with a large invasive mass located on the right lateral aspect of its prepuce. After an incisional biopsy was performed, we diagnosed a cutaneous combined tumour: a squamous cell carcinoma and a soft tissue tumour (sarcoma, Grade III) favouring fibrosarcoma. Based on current literature, this is the first veterinary report of a combined tumour (two admixed tumour types) consisting of these neoplastic entities. The dog underwent aggressive surgical resection comprising a total phallectomy and scrotal urethrostomy to achieve local tumour control. At the time of writing this report, 27 months following surgery, there are no signs of local recurrence or distant metastasis. The prognosis of combined malignant tumours in dogs is largely unknown. This report highlights that long‐term positive outcomes can be achieved in patients with rare combined tumours with aggressive surgical intervention.