Published online Apr 7, 2016. doi: 10.3748/wjg.v22.i13.3644
Peer-review started: November 10, 2015
First decision: December 11, 2015
Revised: December 31, 2015
Accepted: January 30, 2016
Article in press: January 30, 2016
Published online: April 7, 2016
AIM: To investigate feasibility and accuracy of near-infrared fluorescence imaging using indocyanine green: nanocolloid for sentinel lymph node (SLN) detection in gastric cancer.
METHODS: A prospective, single-institution, phase I feasibility trial was conducted. Patients suffering from gastric cancer and planned for gastrectomy were included. During surgery, a subserosal injection of 1.6 mL ICG:Nanocoll was administered around the tumor. NIR fluorescence imaging of the abdominal cavity was performed using the Mini-FLARE™ NIR fluorescence imaging system. Lymphatic pathways and SLNs were visualized. Of every detected SLN, the corresponding lymph node station, signal-to-background ratio and histopathological diagnosis was determined. Patients underwent standard-of-care gastrectomy. Detected SLNs outside the standard dissection planes were also resected and evaluated.
RESULTS: Twenty-six patients were enrolled. Four patients were excluded because distant metastases were found during surgery or due to technical failure of the injection. In 21 of the remaining 22 patients, at least 1 SLN was detected by NIR Fluorescence imaging (mean 3.1 SLNs; range 1-6). In 8 of the 21 patients, tumor-positive LNs were found. Overall accuracy of the technique was 90% (70%-99%; 95%CI), which decreased by higher pT-stage (100%, 100%, 100%, 90%, 0% for respectively Tx, T1, T2, T3, T4 tumors). All NIR-negative SLNs were completely effaced by tumor. Mean fluorescence signal-to-background ratio of SLNs was 4.4 (range 1.4-19.8). In 8 of the 21 patients, SLNs outside the standard resection plane were identified, that contained malignant cells in 2 patients.
CONCLUSION: This study shows successful use of ICG:Nanocoll as lymphatic tracer for SLN detection in gastric cancer. Moreover, tumor-containing LNs outside the standard dissection planes were identified.
Core tip: Sentinel lymph node (SLN) detection using indoyanine green adsorbed to nanocolloid (ICG:Nanocoll) was investigated in 26 patients with gastric cancer. Adsorption of ICG to nanocolloid results in better retention in SLNs and staining of less 2nd tier nodes. After subserosal injection, fluorescent SLN detection using the Mini-FLARE™ system was performed. A mean number of 3.1 SLNs per patient were found and overall accuracy was 90%. In 8 patients, SLNs outside the standard resection planes were identified, that contained malignant cells in 2 patients. To conclude, NIR fluorescence imaging using ICG:Nanocoll as lymphatic tracer identified SLNs in- and outside standard dissection planes.