IBCN 2018: Consensus Molecular Classification of Muscle-Invasive Bladder Cancer

Rotterdam, The Netherlands (UroToday.com) Over the last decade, molecular subtyping efforts from several teams have led to distinct or partially overlapping molecular classifications of MIBC. Recent studies suggest that molecular subtyping on the basis of these classifications could be clinically useful to predict response to chemotherapy and/or immunotherapy.

From Baylor and Chapel Hill classification each with 2 classifications to MDA with 3 classifications and the Lund 10 classification system among other systems there has been a need to standardize these systems. Given increasing evidence for clinical utility of molecular subtyping, there is a need for consensus. Therefore, reaching a consensus on the molecular classification of MIBC has become crucial for further clinical applications and development. We report a joint and comprehensive effort from several teams to reach a consensus on MIBC molecular classification. 1617 MIBC transcriptomes were assigned molecular subtypes according to six published independent classification systems. A network-based approach was used to analyze the relationships between the six systems, cluster the network and construct a consensus classification accordingly. A 6-class consensus system was revealed, successfully reconciling the distinct structures from each input molecular classification. Basal/squamous subtypes and luminal subtypes form the foundation for this system with a single transcriptomic classifier being developed. Further research into the clinical application of molecular subtypes and perhaps further reducing the classification system may further aid in implementation and dissemination in the clinical setting.

Presented by: Aurélie Kamoun Cartes MD,  d’Identité des Tumeurs Program, Ligue Nationale Contre le Cancer, Paris, France

Written by: Stephen B. Williams, M.D., Associate Professor, Division of Urology, The University of Texas Medical Branch, Galveston, TX. and Ashish M. Kamat, M.D. Professor, Department of Urology, Division of Surgery, The University of Texas MD Anderson Cancer Center, Houston, TX at the 16th Annual Meeting of the International Bladder Cancer Network (IBCN) October 11-13, 2018 - the Inntel Hotels Rotterdam Centre, Rotterdam, The Netherlands