Role of non-neoplastic renal parenchyma abnormalities in the population with preoperative CKD

586 Background: Renal cancer is associated with chronic kidney disease. Several studies have shown a 20% rate of preoperative CKD in the population undergoing partial nephrectomy. The non-neoplastic abnormalities (NNA) surrounding a tumor have been suggested as surrogates for long term renal failure. We have endeavored to describe the most relevant features within the above mentioned kidney area in patients with and without preoperative CKD. Methods: We retrospectively reviewed 201 patients who underwent nephrectomy between 2012 and 2014 with available histological assessment of NNA. Additional factors were included in the analysis such as demographic characteristics (age, sex, BMI) and comorbidities (hypertension, diabetes, Charlson comorbidity index). Pathological features were grouped as follows: glomerular (GA), interstitial (IA) or vascular abnormalities (VA). Univariate and multivariate logistic regression analyses were used to determine the associations between NNA and the presence of preoperative CKD stage III. Results: CKD stage III patients were older (68 vs. 56 years, P < .004) and presented a higher rate of DM with end-organ damage (n = 10, 13% vs N = 2 2%). Otherwise, people with and without CKD showed similar demographics. Overall, 56% of patients showed GA, 86% showed IA and 98% of patients presented with VA. In the multivariate analysis adjusted for comorbidities, the most relevant GAs were diabetic glomerulosclerosis (OR 7.32; p = 0.01), segmental sclerosis (OR 4.54; p = 0.0006) and glomerular adhesion (OR 2.80; p = 0.04). In the IA group, interstitial fibrosis (OR 7.36; p < 0.001), tubular atrophy (OR 2.75; p = 0.02) and acute interstitial inflammation (OR 12.47; p = 0.02) were significantly associated with decreased eGFR. Hyperplastic arteriolosclerosis (OR 2.30; p = 0.025) was an independent predictor of baseline eGFR < 60. Conclusions: NNA assessment from surgical specimen is feasible. Patients with baseline CKD present with several abnormalities related to inflammation and healing within the three nephron areas. The further investigation of these abnormalities might have a role in the evaluation of ultimate renal deterioration.