Vestibulovaginal leiomyosarcoma in a mare

Abstract

Summary A 14‐year‐old Quarter Horse mare presented for a mass within the vestibule and vagina resulting in external compression and incomplete occlusion at the external urethral opening with subsequent difficulty urinating. Examination revealed an approximately 15 × 10 cm lobulated mass within the vestibule and caudal vagina attached via a broad base dorsally. Histopathology of the mass identified a low‐grade leiomyosarcoma. Complete resection was not possible, and surgical debulking of the mass was performed during standing sedation using a vessel‐sealing and dividing device. The mare was discharged 3 days post‐operatively without any complications. Recheck examinations performed at 1 month and 8 months’ post‐surgery revealed excellent healing of the surgical site and no apparent tumour regrowth.