Study of the histology of nonneoplastic kidney diseases in nephrectomies and nephroureterectomies performed for tumors.

BACKGROUND

Nephrectomies performed for tumors may harbor nonneoplastic kidney diseases and influence patient outcomes; hence, studying the uninvolved portion of the renal parenchyma at the time of histological tumor diagnosis is prudent. Careful histological assessment of the uninvolved renal parenchyma using light microscopy, special stains and immunofluorescence study gives valuable information regarding pre-existing renal damage.

MATERIALS AND

METHODS

This cross-sectional observational study evaluated 151 partial and radical nephrectomies and nephroureterectomies performed for tumors. Global glomerulosclerosis, tubular atrophy, interstitial fibrosis, interstitial inflammation, and arteriosclerosis were evaluated in the nontumor portion of the kidney, and their severity was scored. Nonneoplastic renal diseases, if present in the uninvolved renal parenchyma, were identified. Preoperative serum creatinine was correlated separately with global glomerulosclerosis, tubular atrophy, interstitial fibrosis, interstitial inflammation, and arteriosclerosis using Spearman's rank correlation.

RESULTS

Positive correlations were observed between global glomerulosclerosis, tubular atrophy, interstitial fibrosis, interstitial inflammation, and arteriosclerosis and preoperative serum creatinine, with a P value of < 0.001. Forty three of 151 cases (28.5%) showed nonneoplastic renal diseases. Diabetic nephropathy (24), hypertensive nephropathy (5), immunoglobulin A nephropathy (5), acute tubulointerstitial nephritis (2), chronic pyelonephritis (2), acute pyelonephritis (1), complement component 1q nephropathy (1), cortical necrosis (1), cholesterol emboli (1), and amyloidosis (1) were the nonneoplastic diagnoses made.

CONCLUSIONS

Tumor nephrectomies can show a spectrum of nonneoplastic diseases in the uninvolved portion of the kidney, and histological changes in the renal parenchyma correlate well with serum creatinine. Thus, a detailed evaluation of the nontumor portion of the kidney is important.