943P - Molecular characterization of metastatic urothelial carcinoma (mUC) in prior or current smokers (PCS) vs non-smokers (NS)

Even though smoking is one of the most recognized risk factors, NS also develop mUC. Identifying molecular drivers of disease progression in NS have the potential to provide novel targets for drug development. We hypothesized that there will be a difference in genomic profile of mUC in NS vs PCS. Tumour tissue undergoing comprehensive genomic profiling (CGP) from patients with mUC were included from NS and age matched PCS within the same time period (2014-19). Clinical and CGP data were retrospectively collected. CGP was performed using FoundationOne (Foundation Medicine, Cambridge, MA), which provides exonic coverage of 315 genes. See table.Table943PTableNon-smokerSmokerP valueMedian age at diagnosis, years (range)66.5 (33-86)67 (35-85)0.94Site of primary0.009Bladder37 (80%)39 (100%)Upper tract9 (19.6%)0Urethral1 (