A urinary assay for mutation and methylation biomarkers in the diagnosis and recurrence prediction of non-muscle invasive bladder cancer patients

Abstract

Background: Currently, the clinical strategy for diagnosis of non-muscle invasive bladder cancer (NMIBC) such as cystoscopy and cytology are invasive and/or with limited accuracy. OncoUrine, a urinary assay for mutation and methylation biomarkers, have showed a high accuracy in the detection of upper tract urinary carcinoma (UTUC) patients with hematuria. The aim of this study is to evaluate the performance of OncoUrine in diagnosis of NMIBC patients.

Methods: In this multicenter prospective study, a total of 203 patients were enrolled, including 60 patients present with hematuria and 143 NMIBC patients under recurrence surveillance. Urine samples were collected before cystoscopy to undergo OncoUrine test. OncoUrine performance was calculated compared to clinical standard methods in hematuria cohort and recurrence surveillance cohort, respectively. Furthermore, NMIBC patients were followed up with a median time of 20.5 months (range 0.03 to 24.03 months) to assess the predictive value of OncoUrine during recurrence monitoring.

Results: For bladder cancer diagnosis, OncoUrine tested 47 samples and achieved a sensitivity/specificity/positive predictive value (PPV)/negative predictive value (NPV) of 80% (95% CI 44.2-96.5)/91.9% (95% CI 77.0-97.9)/72.7% (95% CI 39.3-92.7)/94.4% (95% CI 80.0-99.0) (kappa value 69.4%, 95% CI 44.4-94.3), indicating 72.3% of unnecessary cystoscopy. For recurrence diagnosis, OncoUrine tested 93 samples, and the sensitivity/specificity/PPV/NPV was 100% (95% CI 59.8-100.0)/68.2% (95% CI 57.1-77.7)/22.9% (95% CI 11.0-40.6)/100% (95% CI 92.3-100.0) (kappa value 27.0%, 95% CI 11.1-42.8), indicating 62.4% of spared cystoscopy. What is more, OncoUrine correctly predicted 80% (20/25) of final recurrence with 12/25 (48%) patients who were OncoUrine positive, but cystoscopy negative was followed with recurrence during follow-up. The test result of OncoUrine was also found significantly correlated with recurrence free survival (RFS) of NMIBC patients (median 34.4-month vs unreached; HR 6.0, 95% CI 2.7-13.5, P < 0.0001).

Conclusions: OncoUrine showed potential value to reduce the frequency of unnecessary cystoscopy and the healthcare cost of bladder cancer patients. Patients with positive test results represented a population who were at high risk of recurrence and thus should be subject to frequent surveillance to ensure timely detection of any potential recurrence. This study has been registered in ClinicalTrials.gov with the number NCT04994197 posted on August 2021.

Keywords: Cystoscopy; Diagnosis; Methylation; Mutation; Non-muscle invasive bladder cancer; Recurrence surveillance.