Case Report: Surgical excision of urethral transitional cell carcinoma by total urethrectomy combined with partial cystectomy and vesicovaginal urinary diversion in two female dogs.

Transitional cell carcinoma (TCC), or urothelial carcinoma, is the most common malignant tumor of the canine urinary bladder or urethra, often causing urinary obstruction. While chemotherapy is generally considered as primary management, surgical treatments, including total or partial cystectomy, have occasionally been reported. This report describes two cases of canine urethral TCC managed with total urethrectomy combined with partial cystectomy and vesicovaginal urinary diversion. In both cases, the entire urethral segment and distal urinary bladder were removed while preserving the ureteral orifices. Ventral cystostomy was performed to expose the masses, and special care was taken to maintain vascular supply to the bladder. Postoperative recovery was uneventful. Although chemotherapy was recommended, it was performed in only one case. Urinary flow from the urinary bladder to vagina was successfully diverted without ureteral reimplantation. No recurrence was observed for approximately one year postoperatively in Case 1 and one and a half years in Case 2, respectively. These findings suggest that total urethrectomy combined with partial cystectomy and vesicovaginal urinary diversion is a feasible and effective surgical approach for localized urethral TCC in female dogs.