Naoya Masumori1, Koji Ichihara2, Takeshi Maehana2. 1. Department of Urologic Surgery, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, Japan. Electronic address: masumori@sapmed.ac.jp. 2. Department of Urologic Surgery, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, Japan.
Abstract
OBJECTIVE: To accurately predict the ischemic time (IT) and select candidates for transabdominal laparoscopic partial nephrectomy (LPN). METHODS: Transabdominal LPN was performed for 135 Japanese patients with renal masses <7 cm in diameter between 2009 and 2016 by a single surgeon in a single institute. The renal parenchymal sutures were done with a combination of felt, Hem-o-lok and Lapra-Ty. The original R.E.N.A.L. nephreometry score (NS) was modified as follows. In terms of the tumor size (R), 1, 2, and 3 points were given for ≤2.5, 2.5-4, and >4 cm, respectively. For tumor location (A), 1, 2, and 3 points were given for anterior, on the coronal plane, and posterior, respectively. RESULTS: The median IT was 24.6 minutes. Using the original NS, 64, 65, and 6 patients were categorized into low (4-6), moderate (7-9), and high (10-12) complexity, respectively. With the modified NS, 42, 75, and 18 patients were categorized into low (5-7), moderate (8-11), and high (12-15) complexity, respectively. Pearson's correlation coefficient (R) between the original NS and IT was 0.297, whereas the R was improved to 0.388 when the modified NS was employed. If the modified NS was low complexity, 95.2% achieved IT <30 minutes. Of them, none showed IT ≥30 minutes if the body mass index was <25 kg/m2. CONCLUSION: The modified NS had a better correlation to the IT than the original NS for patients with tumor sizes <7 cm who underwent transabdominal LPN. The modified NS with body mass index is a practical tool to select candidates for transabdominal LPN.
OBJECTIVE: To accurately predict the ischemic time (IT) and select candidates for transabdominal laparoscopic partial nephrectomy (LPN). METHODS: Transabdominal LPN was performed for 135 Japanese patients with renal masses <7 cm in diameter between 2009 and 2016 by a single surgeon in a single institute. The renal parenchymal sutures were done with a combination of felt, Hem-o-lok and Lapra-Ty. The original R.E.N.A.L. nephreometry score (NS) was modified as follows. In terms of the tumor size (R), 1, 2, and 3 points were given for ≤2.5, 2.5-4, and >4 cm, respectively. For tumor location (A), 1, 2, and 3 points were given for anterior, on the coronal plane, and posterior, respectively. RESULTS: The median IT was 24.6 minutes. Using the original NS, 64, 65, and 6 patients were categorized into low (4-6), moderate (7-9), and high (10-12) complexity, respectively. With the modified NS, 42, 75, and 18 patients were categorized into low (5-7), moderate (8-11), and high (12-15) complexity, respectively. Pearson's correlation coefficient (R) between the original NS and IT was 0.297, whereas the R was improved to 0.388 when the modified NS was employed. If the modified NS was low complexity, 95.2% achieved IT <30 minutes. Of them, none showed IT ≥30 minutes if the body mass index was <25 kg/m2. CONCLUSION: The modified NS had a better correlation to the IT than the original NS for patients with tumor sizes <7 cm who underwent transabdominal LPN. The modified NS with body mass index is a practical tool to select candidates for transabdominal LPN.