Revisiting the Prognostic Heterogeneity of AJCC Stage IV Carcinomas of the Upper Urinary Tract

Dividing stage IV upper urinary tract carcinomas into locoregionally advanced and metastatic disease subcategories improves the prognostic utility of the staging system compared to the current AJCC staging system. Given the limitations of a SEER-based study, this concept needs to be externally validated in various settings.