Sentinel Node Mapping Guided by Indocyanine Green Fluorescence Imaging: A New Method for Sentinel Node Navigation Surgery in Gastrointestinal Cancer

Abstract

Background: Recently, gastrointestinal cancer has also been identified as a target for sentinel node navigation surgery (SNNS). This study is the first to determine the feasibility of sentinel node (SN) mapping guided by indocyanine green (ICG) fluorescence imaging in gastrointestinal cancer. Methods: Our series consisted of 22 patients with gastric cancer and 26 patients with colorectal cancer who had undergone standard surgical resection. ICG solution was injected intraoperatively into the subserosa around the tumor. Fluorescence imaging was obtained by a charge-coupled device (CCD) camera with a light-emitting diode with a wavelength of 760 nm as the light source and a cut filter to filter out light with wavelengths below 820 nm as the detector. Results: Immediately after the ICG injection, lymphatic vessels draining the tumor and round-shaped SNs were visualized by their bright fluorescence. Even SNs that were not green in color could be easily and clearly visualized by ICG fluorescence imaging. The SN detection rate and mean number of SNs were 90.9% and 3.6 ± 4.5 (mean ± SD), respectively, in patients with gastric cancer, and 88.5% and 2.6 ± 2.4, respectively, in patients with colorectal cancer. Among the patients with gastric cancer, the accuracy and false-negative rates were 88.9 and 33.3%, respectively, in patients with T₁ stage cancer, and 70.0 and 60.0%, respectively, overall, in all the patients. Among the patients with colorectal cancer, the corresponding values were 100 and 0%, respectively, in patients with T₁ stage cancer, and 82.6 and 66.7%, respectively, overall, in all the patients. Conclusions: Our preliminary results show that ICG fluorescence imaging allows easy, highly sensitive and real-time imaging-guided SN mapping in patients with gastric or colorectal cancer. SN mapping guided by ICG fluorescence imaging could be a promising tool deserving further clinical exploration.

A new stage of sentinel node navigation surgery in early gastric cancer

“…They reported that the SN identification rate and sensitivity for infrared ray electronic endoscopy versus ICG alone were 99.5 % versus 85.8 %, and 97.0 % versus 48.4 %, respectively [15]. Moreover, another teype of fluorescence imaging using the ICG emission system was developed for SN mapping [16]. The photodynamic eye (PDE; Hamamatsu Photonics, Hamamatsu, Japan) is able to observe ICG fluorescence emitted by a light-emitting diode.…”

Sentinel Lymph Node Detection by Blue Dye Versus Indocyanine Green Fluorescence Imaging in Colon Cancer

“…FI may offer better tissue contrast, facilitating detection in deep anatomic regions such as the abdomen, and is easy and safe to perform (13,14,17). Furthermore, ICG-FI is not influenced by the patient's BMI nor by lymphatic invasion, as has been shown for conventional methods, and has been shown to increase SLN detection in comparison with standard techniques (16,18).…”

“…ICG-FI has emerged as a promising new imaging technique for in vivo detection of SLNs of colorectal origin (13,14). FI may offer better tissue contrast, facilitating detection in deep anatomic regions such as the abdomen, and is easy and safe to perform (13,14,17).…”

“…Only few studies have evaluated FI in CRC (13)(14)(15)(16). These studies have shown a potential advantage of FI compared to classical blue dye and lymphoscintigraphy techniques for the detection of deep LN, particularly in obese patients (16).…”

The use of fluorescent dyes and probes in surgical oncology

“…36 However, in these patients very high false negative rates were found (70.0 % for gastric cancer and 66.7% for colorectal cancer), since many of the detected lymph nodes were not the true SLN. The accuracy of SLN detection for patients with T1 stage colorectal cancer as well T1 stage gastric cancer was better than for the higher staged tumors.…”