The current state of renal cell carcinoma grading. Union Internationale Contre le Cancer (UICC) and the American Joint Committee on Cancer (AJCC).

BACKGROUND

The grading of renal cell carcinoma (RCC) has a long history. Currently, there are several grading systems in use throughout the world. There is no consensus regarding which grading system is optimal.

METHODS

A review of the patient outcome cutpoints of several RCC grading systems was conducted to determine the advantages and disadvantages of the different systems.

RESULTS

Almost all authors who have conducted studies of RCC grading agree that it is useful in determining prognosis. The patient outcome cutpoints vary among studies, depending on which grading system is used. Different patient outcome cutpoints have been obtained with the same grading system but different patient groups.

CONCLUSIONS

The ideal RCC grading system has yet to be developed. Any new grading system should be predicated on a study that has separated RCC into the new genetically based subtypes. A new system should also be based on patient outcome, be large enough to account for other prognostic parameters, and be based on reproducible histologic criteria that are easy to apply.