Modified liver hanging maneuver in laparoscopic major hepatectomy: the learning curve and evolution of indications

Background Laparoscopic major hepatectomy is a technically challenging procedure requiring a steep learning curve. The liver hanging maneuver is a useful technique in liver resection, especially for large or invasive tumors, a relative contraindication of the laparoscopic approach. Therefore, this study aimed to evaluate the learning curve for laparoscopic major hepatectomy using the liver hanging maneuver and extended indications. Methods Patients who underwent laparoscopic major hepatectomy using the liver hanging maneuver by a single surgeon from January 2013 and September 2018 were retrospectively reviewed. Our hanging technique involves placing the hanging tape along the inferior vena cava for right-sided hepatectomy or the ligamentum venosum for left-sided hepatectomy. The upper end of the tape was placed at the lateral side of the major hepatic veins. The learning curve for operating time and blood loss was evaluated using the cumulative sum (CUSUM) method. Results Among 53 patients, 18 underwent right hepatectomy, 26 underwent left hepatectomy, and 9 underwent right posterior sectionectomy. CUSUM analysis showed that operative time and blood loss improved after the 30th laparoscopic major hepatectomy. The 53 consecutive patients were divided into two groups (early, patients 1-30; late, patients 31-53). The median operative time was lower in the late group, but the difference was not statistically significant (270 vs. 245 min, p = 0.261). The median blood loss was also significantly lower in the late group (350 vs. 150 ml, p < 0.001). Large tumors (measuring > 10 cm) and tumors in proximity to major vessels were significantly higher in the late group (0 vs. 17.4%, p = 0.018; 3.3 vs. 21.7%, p = 0.036; respectively). Conclusion This study shows that laparoscopic major hepatectomy using the modified liver hanging maneuver has a learning curve of 30 cases. After procedure standardization, the indications have gradually been extended to large or invasive tumors.