The performance of the Xpert Bladder Cancer Monitor Test and voided urinary cytology in the follow-up of urinary bladder tumors

Background. Cystoscopy in complement with urinary cytology represents the gold standard for the follow-up of patients with urinary bladder tumours. Xpert Bladder Cancer Monitor Test (XBC) is a novel mRNA-based urine test for bladder cancer surveillance. The aim of the study was to evaluate the performance of the XBC and voided urinary cytology (VUC) in the follow-up of bladder tumours. Patients and methods. The XBC was performed on stabilized voided urine and VUC was performed on urine samples. The results were compared to cystoscopic findings and histopathological results after transurethral resection of the bladder lesion. Results. For the prediction of malignant histopathological result sensitivity, the specificity and negative predictive value were 76.9%, 97.5% and 93.0% for the XBC and 38.4%, 97.5% and 83.3%, respectively for VUC. For the prediction of suspicious or positive cystoscopic finding sensitivity, the specificity and negative predictive value were 75.0%, 95.2%, and 93.0% respectively for the XBC and 41.7%, 97.6%, and 85.4% for VUC. The sensitivities for papilary urothelial neoplasms of low malignant potential (PUNLMP), low- and high-grade tumours were 0.0%, 66.7% and 100.0% for the XBC and 0.0%, 66.7% and 42.9%, respectively for VUC. Conclusions. The XBC showed significantly higher overall sensitivity and negative predictive value than VUC and could be used to increase the recommended follow-up cystoscopy time intervals. Complementing the XBC and voided urinary cytology does not improve performance in comparison to the XBC alone.

Automated summary

This study evaluated the performance of XBC and VUC in the follow-up of bladder tumors, finding that XBC has higher sensitivity and negative predictive value in predicting malignant histopathological and cystoscopic findings, suggesting it could be used to increase follow-up cystoscopy time intervals.