RENAL nephrometry score: Predicting perioperative outcomes following open partial nephrectomy

Partial nephrectomy has emerged as a standard treatment for small renal masses offering oncologic control equivalent to radical nephrectomy, with preservation of renal function and evidence for equivalent survival. In this study, we evaluated RENAL nephrometry score (RNS) in predicting perioperative outcomes in patients with partial nephrectomy.

This was a prospective observational study conducted from February 2016 to August 2017 which included patients who underwent partial nephrectomy. The patients were divided into three groups depending on the complexity scores (low, moderate, and high). Tumors were assigned RNS and tumor-node-metastasis staging of the clinically malignant tumors was done. Blood loss, warm ischemia time (WIT), and surgical complications were assessed.

A total of 20 patients underwent open partial nephrectomy during the study. There were 4 (20%) low, 11 (55%) moderate, and 5 (25%) high-complexity lesions. Blood loss was significantly different in three groups. All the cases in high-complexity group were performed with clamping the renal vessels with a mean WIT of 29 min. The overall complication rates were significantly different between the groups (P = 0.007); however, majority of the complications were low grade (Grades I and II) and were managed conservatively.

In the present study, RNS was correlated with predicting surgical access route, need for clamping during partial nephrectomy, blood loss, decrease in glomerular filtration rate of operated kidneys, postoperative complications, and tumor grade.