Integrated Methylation and Copy Number Analysis for Noninvasive Bladder Cancer Detection in Urine.

PURPOSE: The molecular analysis of urine cell-free DNA offers a noninvasive tool to advanced bladder cancer (BC) management. Assessment of somatic copy number aberration (SCNA) and DNA methylation analysis have emerged as promising approaches for BC detection. Here, we developed an integrated analysis to assess both SCNA and targeted methylation changes from the same template molecules, which we named the integrated sequencing-based copy number and methylation analysis in urine (iSECURE) method.

MATERIALS AND

METHODS

Urine samples of 30 patients with primary BC, 28 patients with recurrent BC, and 31 hematuria controls were collected at home. Copy number profiling and tumor fraction (TF) estimation were performed by shallow whole-genome enzymatic methyl sequencing. Methylation sequencing libraries were also used for the measurement of a previously validated three-gene methylation marker panel (GALR1/HAND2/NRN1) by the quantitative methylation-specific polymerase chain reaction. Diagnostic accuracy was evaluated by logistic regression analysis using Youden's index for sensitivity and specificity and validated using leave-one-out cross-validation (LOOCV).

RESULTS

TF and methylation levels were significantly higher in patients with BC compared with controls (P < .0001). The individual assays yielded an AUC of 0.91 at 79% sensitivity and 97% specificity for the methylation marker panel and 0.81 at 74% sensitivity and 87% specificity for copy number profiling. The iSECURE workflow yielded a higher diagnostic accuracy with an AUC of 0.94 at 88% sensitivity (90% for primary tumors and 86% for recurrent tumors) and 94% specificity. LOOCV demonstrated an AUC of 0.91 at 84% sensitivity and 90% specificity.

CONCLUSION

We developed a single workflow for copy number profiling and targeted methylation analysis, requiring less input DNA and hands-on time. The high accuracy of iSECURE in home-collected urine samples for detecting both primary and recurrent BC underscores its clinical potential.