A multicenter, retrospective study on impact of immunotherapy in urothelial carcinoma with bone metastases (Meet-Uro01 Study).

401 Background: Considerable numbers of patients (pts) with metastatic urothelial carcinoma (mUC) (approximately 25-47%) develop bone metastases (BoM). Their impact on the efficacy of immunotherapy (IO) is not yet sufficiently investigated. We developed a national collaboration on this issue, with the aim to assess the effect of BoM on survival outcomes of immunotherapy-treated pts in a large retrospective cohort. Methods: Data on pts diagnosed...