Molecular Characterization of Bladder Cancer.

PURPOSE OF REVIEW: Bladder cancer (BCa) management had remained unchanged for 20+ years with clinicians, in contrast to many other cancer types, rarely relying on molecular characteristics to guide management. The past 5 years have yielded significant advances in our knowledge of the molecular basis of BCa and concurrent advances in systemic therapy. We aim to highlight the key developments and potential future direction of BCa management.

RECENT FINDINGS: Next-generation sequencing (NGS) has drastically altered the understanding of muscle-invasive BCa (MIBC) and non-muscle invasive BCa (NMIBC). MIBC molecular subtyping efforts from several groups worldwide grouped into an international consortium into five classes, broadly grouped into basal and luminal subtypes, have attempted to improve prediction of clinical outcomes and treatment response, either chemotherapy or immunotherapy. NMIBC molecular subtyping is yielding similar disease stratification, superior to histopathology alone. Additionally, with new actionable targets being identified for patients non-responsive to traditional therapy, ongoing and upcoming clinical trials are increasingly emphasizing the importance of the molecular testing. The molecular characterization of bladder cancer is rapidly progressing and will likely alter treatment paradigms in the near future.