INTRODUCTION AND OBJECTIVES: The traditional 4-tiered @entity262 ( @entity262 ) is widely accepted as histopathological classification for @entity1358 ( @entity1358 ) and has shown prognostic value. As intra- and inter-observer agreement are sub-optimal, simplified 2- or 3-tiered FGSs have been proposed. We aimed to validate these simplified 2- or 3-tiered FGSs for prediction of @entity5 -specific mortality (CSM) in a large study population from 2 European tertiary care centers. METHODS: We identified and followed-up 2415 @entity1 with @entity1358 who underwent radical or partial nephrectomy in 2 European tertiary care centers. Univariable and multivariable analyses and prognostic accuracy analyses were performed to evaluate the ability of several simplified FGSs (i.e. grades I  +  II vs., grades III  +  IV, grades I  +  II vs. grade III and grade IV) to predict CSM. RESULTS: Independent predictor status in multivariate analyses was proved for the simplified 2-tiered @entity262 (high-grade vs. low-grade), for the simplified 3-tiered @entity262 (grades I  +  II vs. grade III and grade IV) as well as for the traditional 4-tiered @entity262 . The prognostic accuracy of multivariable models of 77% was identical for all tested models. Prognostic accuracy of the model without FG was 75%. CONCLUSIONS: A simplified 2- or 3-tiered @entity262 could predict CSM as accurate as the traditional 4-tiered @entity262 in a large European study population. Application of new simplified 2- or 3-tiered @entity262 may reduce inter-observer-variability and facilitate clinical practice without compromising the ability to predict CSM in @entity1358 @entity1 after radical or partial nephrectomy.

Critical analysis of a simplified Fuhrman grading scheme for prediction of @entity5 specific mortality in @entity1 with XXXX - Impact on prognosis.

@entity5 :: ('MESH:D009369', 'Disease') :: ['cancer'] @entity1 :: ('9606', 'Species') :: ['patients'] @entity1358 :: ('MESH:D002292', 'Disease') :: ['clear cell renal cell carcinoma', 'ccRCC'] @entity262 :: ('MESH:D034721', 'Disease') :: ['Fuhrman grading system', 'FGS']
@entity1358 :: (MESH:D002292,Disease) :: ['clear cell renal cell carcinoma']
