Tissue biomarkers in renal cell carcinoma: issues and solutions

Renal cell carcinoma (RCC) is an aggressive malignancy that is associated with a high rate of metastasis. Although several promising therapeutic strategies are now available for the treatment of patients with metastatic kidney cancer, the prognosis of these patients remains poor. Research is ongoing to identify RCC-specific biomarkers that can improve early diagnosis, surveillance of tumor progression, and prediction of patient prognosis. The identification of biomarkers that may predict response to specific therapies also will be useful in stratifying patients with RCC for treatment selection. Unfortunately, biomarker detection and measurement in kidney tumor tissues can be biased significantly by the lack of standardization in tissue sample acquisition, storage, and analysis. Consequently, the establishment of standardized operating procedures is necessary to maximize the accuracy of tissue-based biomarker assays. Herein, the authors discuss current issues in tissue-based translational research aimed at identifying clinically useful biomarkers for kidney cancer.