Diagnostic status and new explorations in upper urinary tract urothelial carcinoma: a literature review

Upper urinary tract urothelial carcinomas (UTUCs) are characterized by their obscure location, insidious onset, and propensity for early muscle-invasive and lymph node metastasis, resulting in a generally poor prognosis. Clinically, diagnosis primarily relies on urine cytology, computed tomography urography (CTU), and white light ureteroscopy (WL-URS). These methods, however, suffer from low sensitivity, high cost, inefficient testing, patient discomfort, surgery-related complications, and potential tumor implantation. This literature review summarizes the advantages and disadvantages of the existing diagnostic tools for UTUC and discusses promising advancements in the field.

A comprehensive computer-assisted search, supplemented by literature tracing, was conducted to review publications on UTUCs diagnostics from the PubMed, Embase, and Web of Science databases covering the period from 2000 to August 2024. The research focused on synthesizing findings from the selected publications.

Over 100 studies were reviewed, spanning from traditional diagnostic methods like urine cytology, CTU, and WL-URS, as well as newer methods including endoscopic advances, biopsy methods, radiomics, immunocytology [urinary tumor cell (UTC) assay], urinary genetic tests (identifying chromosomal abnormalities, DNA mutations, DNA methylation, and RNA), and hematological and urinary tests for microRNAs (miRNAs) and proteins (plasma protein classifiers). While traditional methods have been extensively evaluated, they remain suboptimal in terms of effectiveness, safety, patient satisfaction, and cost. Emerging diagnostics and molecular markers show promise, such as the high sensitivity of the urinary UTC assay for early-stage tumors and the non-invasive nature of various urinary molecular tests, along with the high accuracy of plasma protein classifiers. However, these new tools generally lack thorough evaluation and are often restricted to reports from single institutions or simple differentiation of cancerous cases from controls under experimental conditions.

Traditional diagnostic methods for UTUCs exhibit significant limitations, which newer tools and molecular markers are poised to address. However, comprehensive evaluations of these innovations are required to confirm their efficacy.