Histological grading of renal cell carcinoma

The Erlangen system of histologic grading of the malignancy of renal cell cancers is described in detail. It takes into consideration the type of cell and pattern of the tumor and differentiates between grades 1, 2, and 3. Grade 1 was observed in 10%, grade 2 in 51%, and grade 3 in 39% of the cases. The difference in the 5-year survival rates between tumors of grade 3 and those of tumors of grades 1 and 2 is statistically significant.