Efficacy of indocyanine green as a single tracer for sentinel lymph node-guided basin dissection in gastric cancer surgery: a multicenter prospective feasibility study (SDR-01)
Hoon Hur, Sang-Yong Son, Hoseok Seo, Han Hong LeeBackground:
Sentinel node navigation surgery is an emerging technique in function-preserving treatment for gastric cancer. This study aimed to evaluate the feasibility of sentinel lymph node-guided basin dissection using indocyanine green (ICG) as a single tracer, visualized by a laparoscopic near-infrared (NIR) imaging system.
Methods:
In a multicenter, prospective, single-arm trial, patients with clinical T1-2N0 gastric adenocarcinoma were enrolled. After intraoperative endoscopic ICG injection, sentinel nodes were identified in real time using NIR imaging, and basin lymph nodes, including the sentinel nodes, were dissected. All patients subsequently underwent standard gastrectomy with lymphadenectomy. The primary endpoint was to determine whether the sensitivity of the single-dye method was non-inferior to the predefined threshold for the dual-tracer (dye plus radioisotope) method in detecting sentinel lymph node metastasis.
Results:
From October 2019 to January 2023, 219 patients were enrolled. Intraoperative endoscopic ICG injection was successful in 185 patients, and sentinel nodes were identified in 181 cases (detection rate: 97.8%). The mean basin dissection time was 7.4 ± 5.1 minutes, with a mean total operative time of 161.8 ± 29.9 minutes. No morbidity was attributable to basin dissection. Among the 181 patients, 24 had lymph node metastases. The false-negative proportion for sentinel lymph node-guided basin dissection was 3.3% (6 of 181). The sensitivity of the single-tracer ICG-NIR approach was 75%, which did not meet the prespecified non-inferiority threshold (80%) derived from dual-tracer performance.
Conclusion:
Single-tracer ICG-NIR sentinel lymph node–guided basin dissection failed to demonstrate non-inferiority to the dual-tracer benchmark. Despite its feasibility, it is not suitable as a stand-alone guide for function-preserving decision-making and requires further refinement and controlled validation with oncologic follow-up.