Methylation study of the Paris system for reporting urinary (TPS) categories

Aims Bladder EpiCheck is one of several urinary tests studied to identify bladder tumours and analyses 15 methylation biomarkers determining bladder cancer presence on the basis of methylation profile. Methods 374 patients diagnosed with high-grade non-muscle invasive bladder cancer were treated and followed for 1 year with voided urine cytology and white-light cystoscopy and biopsies according to European Association of Urology Guidelines. 268 cases were diagnosed with high-grade papillary carcinoma, while 106 cases were carcinoma in situ. Bladder EpiCheck test was performed together with cytology in all cases. Results Comparing cytological categories of negative for high-grade urothelial carcinoma (NHGUC) and atypical urothelial cells (AUCs), we found that an EpiScore <60 correlates with NHGUC (p=0.0003, Fisher's exact test), while comparing AUC and suspicious for high-grade urothelial carcinoma (SHGUC) or SHGUC and high-grade urothelial carcinoma (HGUC) categories, an EpiScore >= 60 correlates with SHGUC and HGUC, respectively (p=0.0031 and p=0.0027, Fisher's exact test). In each TPS category, we found that sensitivity, specificity, Positive Predicitve Value (PPV) and Negative Predictive Value (NPV) of the Bladder EpiCheck test in HGUC category were higher than those observed in SHGUC group (sensitivity=98%, specificity=100%, NPV=85.7%, PPV=100% vs sensitivity=86.6%, specificity=52.3%, NPV=84.6%, PPV=56.5%). Conclusions Analysing methylation study results, we demonstrated that different TPS cytological categories also carry a distinct molecular signature. Moreover, our results confirm that cytological categories SHGUC and HGUC are different entities also from a molecular point of view and should continue to represent distinct groups in TPS.

Automated summary

The study analyzed the combination of Bladder EpiCheck with cytology and found that in different cytological categories, the sensitivity, specificity, Positive Predictive Value (PPV), and Negative Predictive Value (NPV) of Bladder EpiCheck were higher in the High-grade Urothelial Carcinoma (HGUC) category compared to the Suspicious for High-grade Urothelial Carcinoma (SHGUC) group. This suggests that molecular signatures of different TPS cytological categories vary and that SHGUC and HGUC should be considered distinct entities in TPS.