Utility and safety of near-infrared fluorescent marking clips for tumor localization in robot-assisted laparoscopic gastric cancer surgery.

[PURPOSE] Precise resection margins are crucial in gastric cancer surgery to optimize oncological outcomes and reduce postoperative functional disorders. Fluorescent marking clips (ZEOCLIP FS; Zeon Medical Co, Ltd) have demonstrated potential in improving resection line accuracy during laparoscopic gastrectomy. However, the original ZEOCLIP FS contained insufficient fluorescent dye, limiting its visibility with the Firefly mode of the da Vinci Surgical System. To address this limitation, a new version with increased dye concentration, the ZEOCLIP FS Marker, was developed. This study aimed to evaluate the utility and safety of the enhanced ZEOCLIP FS Marker in robot-assisted gastric cancer surgery.

[METHODS] A prospective observational study was conducted in 20 patients diagnosed with gastric cancer (cT1-T4aNanyM0). Fluorescent clips were preoperatively placed along the intended resection margins, and the Firefly mode was used intraoperatively to detect the clips. The primary endpoint was the detection rate, defined as the proportion of cases in which all preoperatively placed clips were identified under fluorescence. The secondary endpoints included detection time, thread-to-clip distance, and complications.

[RESULTS] The detection rate of the clips under fluorescence was 75.0% (90% CI, 54.4%-89.6%). At least 1 fluorescent clip was detected in all patients (20/20), facilitating approximate tumor localization. Of the 51 clips placed, 45 (88.2%) were identified under fluorescence. The median thread-to-clip distance was 3 mm (range, 0-13). Clip-related complications were minimal, with 1 case of postoperative anastomotic leakage and 2 unrelated complications.

[CONCLUSION] The enhanced ZEOCLIP FS Marker seems effective and safe for marking gastric transection lines in robot-assisted surgery. Further prospective interventional studies are warranted to confirm whether the use of fluorescent clips can reduce the reliance on intraoperative endoscopy.