Survey on the use of invasive urodynamic study in patients with orthotopic neobladder urinary diversion: Searching for a common ground

Radical cystectomy (RC) is a standard treatment for advanced or high-risk non-muscle invasive bladder cancer. Although orthotopic neobladder (ONB) typically improves quality of life (QoL), lower urinary tract symptoms (LUTS) are common and can negatively impact post-operative outcomes. Despite the possible importance of urodynamic studies (UDS) in this setting, there is limited evidence on standardised protocols for their execution, terminology and interpretation. The primary objective of this survey is to investigate how and when major Italian oncological centres perform UDS on patients with ONB. A survey consisting of 32 items. This survey was distributed to Italian oncological centres between September 2024 and January 2025. Responses were collected using the Google Forms® platform. Approximately 37% of contacted centres responded to the survey, and 64% of them performed UDS in this setting. UDS timing varied, with 31.8% performed at 6 months post-surgery, 13.6% at 3 months, and 4.5% at 12 months. During cystomanometry the first sensation of filling was described as any abdominal change in 71.4% by survey participants and there was no consensus on normal pressure values for stopping the filling. During pressure-flow studies, obstruction was assessed in 36.4% of respondents using native bladder nomograms, while significant variability was observed in post-void residual volume (PVR, 31.8% considering ≤ 100 mL acceptable, 13.6% ≤ 150 mL and 13.6%≤ 50 mL. The survey revealed substantial heterogeneity in UDS assessment and parameters designed for native bladders were often applied to ONB patients, raising concerns about their appropriateness. These results highlight the need for standardised protocols and guidelines in assessing functional outcomes.