Diagnostic Accuracy of MCM5 for the Detection of Recurrence in Non Muscle Invasive Bladder Cancer Follow up: A Blinded, Prospective Cohort, Multicentric European Study

Purpose: Detection of MCM5 containing cells in urine has been shown to be indicative for the presence of a bladder tumour in primary diagnosis. The objective of this study was to evaluate diagnostic performance of ADXBLADDER in patients undergoing cystoscopic surveillance in Non Muscle Invasive Bladder Cancer (NMIBC) follow-up. Materials and methods: A multicentric prospective blinded study was carried out at 21 European centres in patients undergoing cystoscopy for NMIBC surveillance, diagnosed in the preceding 2 years. Urine was collected from all eligible patients and ADXBLADDER-MCM5 test was performed. Performance characteristics were calculated by comparing MCM5 results to the outcome of cystoscopy plus pathological assessment. Results: Of 1431 eligible patients enrolled, 127 were diagnosed with a bladder cancer recurrence. The overall sensitivity for the ADXBLADDER MCM5 test in detecting bladder cancer recurrence was 44.9% (95% CI 36.1-54%) with a 75.6% sensitivity for non pTaLG tumours (95% CI 59.7-87.6%). Specificity was 71.1% (95% CI 68.5-73.5%). The overall negative predictive value was 93% (95% CI 91.2-94.5%) however ADXBLADDER was able to rule out the presence of a non-pTaLG recurrent tumour with a NPV of 99.0% (95% CI 98.2-99.5%). No statistically significant differences in the performance of ADXBLADDER were observed as a result of age or sex. Conclusions: This large blinded prospective study demonstrates that in the follow-up of NMIBC patients ADXBLADDER is able to exclude the presence of the most aggressive tumours with a NPV of 99%. These results indicate that ADXBLADDER could be incorporated in the follow-up strategy of NMIBC.