Molecular Pathology of Urothelial Carcinoma

Recent advances in molecular biology and next-generation sequencing technologies have greatly enhanced our knowledge and understanding of the genomic landscape of urothelial carcinoma (UC) and provided insights into the molecular biology and pathogenesis of UC and some of its variants.1 One of the main challenges in UC is the presence of considerable intratumoral and intertumoral heterogeneity that can be appreciated at the clinical, morphologic, genomic, and transcriptomic levels.2 Many UC variant histologies are recognized and can be pure or, more frequently, mixed with UC-not otherwise specified. These variants historically have been based on defined morphologic features and more recently new molecular studies provided valuable insights into them. 1,3 The aim of this review is to provide an update on recent advances in molecular features of UC and a subset of its variants and potential clinical applications.