Prognostic and therapeutic impact of the histopathologic definition of parenchymal epithelial renal tumors

Abstract

Context: In the last few years, the treatment of renal cell carcinoma (RCC) has progressed significantly, and some histopathologic issues have become important for selection and follow-up after medical and surgical therapies.

Objective: The aim of this collaborative article is to review the most recent literature on the role of traditional histopathologic features obtained from renal core biopsy or nephrectomy specimens in the management of confined, locally advanced, and metastatic RCC.

Evidence acquisition: A nonsystematic review of the literature was performed in April 2010 using the Medline database. Multiple free-text searches were performed for the following items: renal cell carcinoma, clear cell, papillary, chromophobe, histologic* subtype*, histotype*, nuclear grade*, necrosis, sarcomatoid differentiation, biopsy, molecular marker*, and cytogenetic marker*. A total of 2369 records were retrieved from Medline, and 263 full-text studies were considered and partially included in the present review. A panel of experts reached consensus on the main subheadings of this paper.

Evidence synthesis: Core needle biopsies can provide important information that is useful to avoid the overtreatment of benign tumors and to help plan watchful waiting or minimally invasive treatments in selected patients. Tumor histotype is fundamental in the pathologic report. In the context of integrated prognostic systems, the combination of the most important clinical and pathologic factors (TNM stage, Fuhrman nuclear grade, presence of necrosis, microvascular invasion, and sarcomatoid dedifferentiation) allows us to reach a high prognostic accuracy. These models can be used to select patients suitable for adjuvant protocols, to design an appropriate follow-up schedule, and to provide careful patient counseling. Molecular and cytogenetic markers should be further evaluated.

Conclusions: The histopathologic definition of parenchymal epithelial renal tumors is fundamental to plan the management and follow-up of patients with locally confined, locally advanced, and metastatic RCC.