Neurogenic bladder (NB) is considered a risk factor for bladder cancer (BCa). In this population the mortality rate is high due to the significant prevalence of aggressive behavior with a high proportion of squamous cell carcinoma (SCC). However, there is still no consensus regarding screening and early diagnosis strategies. The aim of this study was to report data and outcomes of BCa in individuals attending two tertiary referral centers for NB follow-up and evaluate the possible relationship between NB management and tumor staging at diagnosis.

We retrospectively collected all pre-, intra- and post-operative data of our patients having NB for ≥ 5 years and BCa diagnosed from January 2010 to December 2020. Patients were divided into two groups: muscle invasive BCa (MIBC) vs. non-MIBC. We conducted a descriptive statistical analysis and used chi-squared test to evaluate differences in categorical variables between the two groups. This study obtained the Institutional Review Board approval.

BCa was detected in 25 individuals having NB, mostly due to spinal cord injury (60%) and myelomeningocele (16%). The median age at diagnosis was 55 years (range: 32-83), while the median time lapse since the NB diagnosis was 37 years (range: 5-58). Macrohematuria was the presenting symptom in 48% patients. Periodical cystoscopies for botulinum toxin intradetrusor injections revealed BCa in 28% cases. BCa was incidentally discovered in 3 patients undergoing annual urinary tract ultrasonography (US) due to their NB follow-up. Urine cytology was performed in 20 cases, resulting negative (n=16, 80%), positive (n=1, 5%) and atypical (n=3, 15%). Radical cystectomies were performed in 20/25 patients; most cases (70%) were followed by different-graded surgical complications. SCC was observed in 6 (24%) cases. After a median follow-up of 28.5 months, 7 patients died due to BCa. Considering MIBC (n=16) vs. non-MIBC (n=9) groups, no statistically significant differences were detected in all variables, except for the mode of BCa diagnosis. Specifically, non-MIBC was detected in 7/11 (63.6%) cases undergoing periodical cystoscopies and US scans compared to 2/14 (14.3%) patients in the cluster not undergoing any regular exam for NB (p value = 0.011).

Our results confirm that BCa in individuals with NB often occurs at an advanced stage and is associated with a poor prognosis and death. In particular, BCa presents commonly as SCC and MIBC in people with NB. The rate of surgical complications is significantly high in this frail population. All these issues highlight the importance of an early diagnosis, even if the optimal strategy has not been identified so far. According to our experience, we observed a higher rate of non-MIBCs in individuals undergoing periodical cystoscopies and US, while urinary cytology proved to be associated with poor accuracy.

Our study outlined a lower stage of BCa at diagnosis in patients affected by NB without any suspicious signs for BCa (e.g. macrohematuria) but submitted to cystoscopy for botulinum toxin intradetrusor injections or strictly monitored for their NB condition through US. This consideration highlights the importance that periodical follow-up and endoscopic treatments for NB may be helpful to reduce the risk of a delayed BCa diagnosis. Larger studies are mandatory to confirm our findings and better optimize NB surveillance and BCa screening.