Partial cystectomy and adjuvant chemotherapy are associated with prolonged survival in dogs and cats with nontrigonal urothelial carcinoma (2010-2014).

Abstract

OBJECTIVE: To evaluate survival outcomes, complication rates, and prognostic factors for dogs and cats with urothelial carcinoma (UC) treated with partial cystectomy. METHODS: Medical records of client-owned dogs and cats with UC treated with partial cystectomy between January 2010 and December 2024 were retrospectively reviewed. Data regarding signalment, tumor and surgical characteristics, adjuvant therapy, and outcomes were collected. Disease-free interval and median survival time (MST) were estimated via the Kaplan-Meier method. Prognostic factors were identified with log-rank tests and Cox proportional hazards modeling. RESULTS: 30 animals were included (20 dogs, 10 cats). Overall MST for 27 patients was 512 days and disease-free interval was 255 days. Mean survival time was 498 days for dogs and 730 days for cats. Complete surgical margins were associated with longer MST on univariate analysis. On multivariate analysis, complete surgical margins (hazard ratio, 0.27) and adjuvant chemotherapy (hazard ratio, 0.24) were independent positive prognostic factors. Postoperative complications occurred in 16 of 30 patients (53%). Local recurrence was documented in 12 patients (40%) and distant metastasis in 5 patients (17%). CONCLUSIONS: Partial cystectomy, as part of a multimodal treatment plan including adjuvant medical therapy, can be associated with prolonged survival in select dogs and cats with nontrigonal UC. The achievement of complete surgical margins is a critical predictor of outcome. CLINICAL RELEVANCE: The procedure carries a substantial risk of complications and eventual disease progression, underscoring the importance of careful case selection and comprehensive client counseling regarding the palliative intent of therapy.