To identify whether and which of pathological features of sarcomatoid differentiation (SD) in renal cell carcinoma (RCC) can be used as independent predictors associated with overall survival (OS).
After institutional review board approval, patients with a diagnosis of sarcomatoid RCC (sRCC), spindled RCC, or RCC with the presence of spindle cells between 2003 and 2017 were further selected and re-examined.