Upper urothelial tract high-grade carcinoma: comparison of urine cytology and DNA methylation analysis in urinary samples

Numerous studies showed that bladder urothelial carcinoma and upper urothelial tract carcinoma (UTUC) display clinical and genomic similarities. In order to analyze that the same panel of biomarkers used in the diagnosis of bladder urothelial carcinoma could be suitable for early detection of UTUC, we performed a retrospective study in which we analyzed Bladder EpiCheck scores in the urinary samples obtained by selective ureteral catheterization in a high-grade UTUC cohort, correlating the results with urinary cytology and diagnostic urethral biopsies. The present study represents a retrospective analysis of 82 patients with clinically localized high-grade UTUC (60 renal pelvis UTUC, 22 ureter UTUC) who had undergone a radical nephroureterectomy (RNU) at our Urology department from June 2018 to November 2020. Before any surgical procedure, one sample of urine, obtained by selective ureteral catheterization, was collected for each patient for cytological examination, and the remaining material was stored for the Bladder EpiCheck test. Our results showed that the sensitivity of the methylation test for high-grade UTUC was about 97.4%, significantly higher than the sensitivity of urinary cytology either considering the HGUC cytological diagnosis or including in the positive cases the SHGUC cytological diagnosis (97.4% versus 59% or 70.5%). The methylation analysis of urinary samples may represent a valid tool in the diagnostic process of patients with suspected UTUC. In cases with a difficult clinical decision after upper urinary tract biopsy and cytology, the methylation test could assist in the clinical management of UTUC patients.