Updates on Molecular Classification and Diagnostics of Upper Urinary Tract Urothelial Carcinoma

Pukar MaskeyNepal Moderator

Haruki KumeJapan Speaker Updates on Molecular Classification and Diagnostics of Upper Urinary Tract Urothelial CarcinomaUpper urinary tract urothelial carcinoma (UTUC) is a relatively common form of urothelial cancer. However, the molecular mechanisms underlying its carcinogenesis and progression have not been well understood. Most urologists previously believed that the mutational profiles of UTUC and urothelial bladder carcinoma (UBC) were similar. In 2021, by analyzing 198 cases of upper urinary tract cancer, we identified five distinct molecular subtypes of UTUC, each characterized by unique gene expression patterns, tumor locations/histology, and clinical outcomes: hypermutated, TP53/MDM2, RAS, FGFR3, and triple-negative subtypes. Notably, the hypermutated subtype, accounting for approximately 5% of all cases, was predominantly associated with Lynch syndrome, aligning with previous reports. In contrast, UBC is known to be rarely linked to Lynch syndrome. In this plenary session, I will delve into the molecular pathogenesis of UTUC and discuss future perspectives in this field.