Learning Curve for Identification of Sentinel Lymph Node Based on a Cumulative Sum Analysis in Gastric Cancer

Abstract

Background/Aims: Lymph node metastasis is the most important point to consider when deciding on the modality of resection in patients with early gastric cancer. This study was conducted to evaluate the learning curve for identification of sentinel lymph nodes in patients with gastric cancer. Methods: The investigators included the results from 2 prospective series of sentinel lymph node mapping. Cumulative sum (CUSUM) analysis was performed to assess the learning curves for identification of sentinel lymph nodes at CUSUM target success rates of 95%. Results: One surgeon performed 135 sentinel lymph node mappings for 2 prospective series. The success rate exceeded 90%. The learning period for gastric cancer sentinel node mapping was calculated to be 26 cases for achieving a 95% success rate. Multiple logistic regression analysis for successful detection of sentinel nodes showed that surgical experience of sentinel lymph node mapping was an independent factor for successful detection of sentinel nodes. Conclusions: This study suggests that the learning period for identification of sentinel lymph nodes in gastric cancer would be 26 cases. In clinical trials for gastric cancer with sentinel lymph node mapping, the learning curve should be considered to minimize bias due to surgical factors.