Abstract
Purpose: Investigations for diagnosis and assessment of colovesical fistula (CVF) include cross-sectional imaging and endoscopic evaluation. Routine pre-operative cystoscopy for CVF remains controversial. The primary aim of this study was to assess the incidence of bladder cancer and the need for routine cystoscopy during the investigation of CVF. Secondary aims were to describe the diagnosis and management of CVF and determine the value of post-operative cystograms.
Methods: A retrospective observational study was performed at a tertiary referral hospital in New Zealand. Patients were identified from the clinical coding database between 1st January 2000 and 31st December 2021. Demographic, diagnostic, and peri-operative data were collected.
Results: The 88 patients with CVF were identified and included in the analysis. 73.8% of CVF were caused by diverticular disease, followed by colorectal cancer (14.8%), iatrogenic complication (5.7%), bladder cancer (3.4%) and gynecological cancer (2.3%). All patients with CVF due to bladder cancer had a known bladder cancer at the time of CVF diagnosis, and no occult cases of bladder cancer were found during or after surgical resection. The 18 patients had a post-operative cystogram. One patient had a post-operative bladder leak, which was routinely diagnosed on a planned early post-operative cystogram.
Conclusion: CVF due to bladder cancer is rare, and when it occurs, it is likely to be in those with a pre-existing diagnosis of bladder cancer. Pre-operative cystoscopy should be used selectively and is not routinely required. Post-operative cystogram may be reserved for cases with large bladder defects or complex bladder repair.