The pathological evaluation of nonneoplastic kidney disorder in tumor nephrectomy specimens

Renal cell carcinoma (RCC) comprises 2%–3% of all visceral and 80%–85% of all adult kidney malignancies. Nephrectomy is the treatment of choice for renal tumors. The accurate pathological evaluation of nonneoplastic renal parenchyma in nephrectomy specimens is important for subsequent management. Eighty-two patients with RCC who underwent surgery at Imam Khomeini Hospital, Urmia, Iran, from April 2006 to February 2015 were studied. Paraffin blocks of the hospital archives were stained by hematoxylin and eosin (H and E) and periodic acid-Schiff staining. Microscopic examination was performed on nontumoral portions that were in the farthest possible distance from the tumor. Out of total 82 cases, 24 (29.3%) had normal renal parenchyma and 58 (70.7%) had pathological changes in renal parenchyma. The most frequent pathological findings were vascular sclerosis with parenchymal scarring and pyelonephritis. Other findings include focal and diffuse mesangial hypercellularity, eight; focal segmental glomerulonephritis, five; membranoproliferative glomerulonephritis, three; and membranous glomerulonephritis, two. Parenchymal scarring and vascular change included 36% of clear cell type, 41% of papillary type, and 53.8% of chromophobe type. Although there is not any statistical relation between the gender of patients and pathological findings, there was an obvious correlation between age and pathological findings. Before the age of 55 years, vascular sclerosis with parenchymal scarring and glomerular diseases and then chronic pyelonephritis are more prevalent.