Benign tumors and tumor-like lesions of the adult kidney - part I: Benign renal epithelial neoplasms

The spectrum of renal neoplasms has expanded in recent years. Although most of the work taking place in this field has concerned malignant neoplasms o f the kidney, there have been significant improvements in our knowledge of benign renal tumors and tumor-like lesions, especially in renal cell adenom a, renal oncocytoma, and renal angiomyolipoma. Awareness and knowledge of t hese benign lesions is important because they are often included in the dif ferential diagnoses of malignant tumors, with which they may be confused bo th clinically and pathologically. The authors review the topic of benign re nal neoplasms and tumor-like lesions that occur in adults, emphasizing some of the newly described aspects of these lesions.