Assessment of diagnostic Value of Indocyanine Green (ICG) for lymph node metastasis in laparoscopic subtotal gastrectomy with D2 lymphadenectomy for gastric cancer. A prospective single-center study

Abstract

PurposeEvaluation of diagnostic value for lymph node metastasis and lymph node identification using Indocyanine Green (ICG) fluorescence in laparoscopic subtotal gastrectomy for gastric cancer. MethodsA prospective study on 79 patients who underwent radical subtotal gastrectomy with the use of ICG-guided lymph node dissection. The sensitivity and specificity of the ICG fluorescence lymphography method in detecting metastatic lymph nodes were evaluated. ResultsA total of 79 patients underwent surgery. The number of lymph nodes (LNs) were retrieved: 2.992 LNs, of which 2.392 were fluorescent (79.9%) and 600 were non-fluorescent (20.1%). The average number of lymph nodes dissected was 37.7 ± 11.8 LNs, and the average number of fluorescent lymph nodes was 30.3 ± 11.1; the LN metastasis rate in the total lymph nodes and in the ICG group were 6.79% and 7.34%, respectively. The median number of retrieved LNs in patients with LN metastases [32 (IQR 26-44)] was higher than in patients without LN metastases [26 (IQR 21-36)], (p=0.348). The median number of fluorescent LNs was significantly higher in patients with LN metastases [32 (IQR 26-44)] than in those without LN metastases [26 (IQR 21-36); p<0.001]. The sensitivity of ICG in metastasis detection was 75.86% (22 out of 29 patients), with a false-negative (FN) rate of 24.14% (7 out of 29 patients). For the identification of metastatic LNs, the sensitivity of ICG was 90.7%, with the specificity of 20.8%. The negative predictive value of non-fluorescent LNs was 97%. ConclusionICG fluorescence lymphography-guided lymphadenectomy can clearly visualize the lymphatic system and the lymph nodes alongside the tumor. The high sensitivity in detecting metastatic lymph nodes and the high negative predictive value of a non-fluorescent lymph nodes suggest that this is an effective method for clinically radical gastrectomy for gastric cancer.