How do organ-specific metastases affect prognosis and surgical treatment for patients with metastatic upper tract urothelial carcinoma: first evidence from population based data

To evaluate the prognostic roles of organ-specific metastases and analyze the impact of organ-specific metastases on surgical resection of the primary tumor for metastatic upper tract urothelial carcinoma (UTUC) patients. A population-based study using Surveillance, Epidemiology, and End Results database was carried out. Kaplan-Meier analysis were used for survival comparisons. Multivariate Cox regression model was employed to analyze the effect of distant metastatic organs on overall survival (OS) and cancer specific survival (CSS). 337 patients from 2010 to 2014 were included. Patients with brain metastasis had significantly worse OS (p = 0.012) and CSS (p = 0.004). Liver metastasis could only independently predict unfavorable OS rather than CSS. Multivariate analysis showed that patients with bone, lung or distant lymph node metastasis was not independent prognostic factor for patients' survival. Surgical resection of the primary tumor was an independent favorable predictor for both OS (p = 0.004) and CSS advantages (p = 0.006). In subgroup analysis, patients with multiple organs of metastasis or distant lymph node involvement could benefit from surgical resection of the primary tumor. However, the presence of liver or lung metastasis could make such surgery become meaningless from the point of survival benefits. Our study showed that brain metastasis independently predicted both unfavorable OS and CSS for metastatic UTUC patients while liver metastasis was only associated with worse OS. More importantly, surgical resection of the primary tumor might still lead to survival benefits for highly selected patients.