Pathologic evaluation of non-neoplastic renal parenchyma in partial nephrectomy specimens

This study aimed to identify non-neoplastic pathologic changes in partial nephrectomy specimens of patients without a known history of medical comorbidities. Routine analysis of this tissue may allow the clinician to identify subclinical renal disease.

We retrospectively reviewed our database of patients who underwent open partial nephrectomy for a small renal mass. Non-neoplastic tissue of partial nephrectomy specimens of patients without a known history of chronic kidney disease, diabetes mellitus, hypertension, or coronary artery disease was evaluated for glomerular, interstitial, and vascular pathologic changes.

A rim of non-neoplastic tissue was adequate for pathologic evaluation in 91.8% of specimens. A total of 45 patients were studied with a median age of 52.0 years. Atherosclerosis was the most commonly identified pathologic finding in 9 (20%) patients, followed by mesangial expansion and interstitial fibrosis, each found in 8 (17.8%) patients. Linear regression found interstitial fibrosis to be the only pathologic lesion associated with preoperative serum creatinine (coefficient = 0.697, P = 0.001). Male gender was also associated with a higher preoperative creatinine (coefficient = 0.270, P = 0.034). Postoperative serum creatinine was not associated with any of the examined lesions.

Current surgical techniques provide adequate non-neoplastic tissue for pathologic evaluation. We observed a striking degree of pathologic disease in patients without a known history of medical comorbidities. Routine inspection of the non-neoplastic parenchyma of partial nephrectomy specimens should be performed as it can alert the clinician to presence subclinical renal disease allowing for medical intervention.