Disseminated peritoneal leiomyomatosis in an Australian cattle dog

Abstract A 2‐year‐old, entire Australian cattle dog bitch presented with abdominal enlargement and lethargy. Laparotomy revealed multifocal cystic structures up to 15 cm in diameter in the mesentery and nodules of 2 mm on the gastric serosa. Histopathology and immunohistochemistry identified disseminated peritoneal leiomyomatosis (DPL). Complete removal seemed impossible, and due to repeated recurrence, pigtail catheters were implanted, allowing continuous peritoneal drainage. Ovariohysterectomy was conducted to reduce any hormonal effects. This is the first report of canine DPL with detailed histopathological characterisation and long‐term stabilisation of the patient. Although a rare cause of cysts and nodules in the abdominopelvic cavity in dogs, DPL should be considered as a differential diagnosis of cancerous, parasitic or other cystic masses. Definitive diagnosis requires histopathology. Similar to DPL in people, either complete surgical excision or drainage combined with gonadectomy to remove hormonal stimulation seems advisable.