Introduction: Robot-assisted radical cystectomy (RARC) has gained momentum in the management of muscle invasive bladder cancer (MIBC). Predictors of RARC outcomes are not thoroughly studied. We aim to investigate the implications of preoperative hydronephrosis on oncological outcomes.
Patients and methods: This study analysed data from the Asian RARC consortium, a multicentre registry involving nine Asian centres. Cases were divided into two groups according to the presence or absence of pre-operative hydronephrosis. Background characteristics, operative details, perioperative outcomes, and oncological results were reviewed. Outcomes were (1) survival outcomes, including 10-year disease-free survival (DFS) and overall survival (OS), and (2) perioperative and pathological results. Multivariate regression analyses were performed on survival outcomes.
Results: From 2007 to 2020, 536 non-metastatic MIBC patients receiving RARC were analysed. 429 had no hydronephrosis (80.0%), and 107 (20.0%) had hydronephrosis. Hydronephrosis was found to be predictive of inferior DFS (HR = 1.701, p = 0.003, 95% CI = 1.196-2.418) and OS (HR = 1.834, p = 0.008, 95% CI = 1.173-2.866). Subgroup analysis demonstrated differences in the T2-or-above subgroup (HR = 1.65; p = 0.004 in DFS and HR = 1.888; p = 0.008 in OS) and the T3-or-above subgroup (HR = 1.757; p = 0.017 in DFS and HR = 1.807; p = 0.034 in OS).
Conclusions: The presence of preoperative hydronephrosis among MIBC patients carries additional prognostic implications on top of tumour staging. Its importance in case selection needs to be highlighted.
Keywords: bladder cancer; hydronephrosis; muscle-invasive bladder cancer; pre-operative assessment; robot-assisted radical cystectomy.