Safety and efficacy of carbon nanoparticle suspension injection and indocyanine green tracer-guided lymph node dissection during robotic distal gastrectomy in patients with gastric cancer

BACKGROUND: There is a lack of comparative analyses on the use of carbon nanoparticle suspension injection (CNSI) and indocyanine green (ICG) tracer technology for lymph node detection and their perioperative safety in robotic radical gastrectomy. METHODS: A retrospective analysis was performed on patients who underwent robotic distal gastrectomy between November 2019 and November 2020. Patients were assigned to the CNSI group, the ICG group, or the control group. The number of lymph nodes detected, number of lymph nodes detected at each station, number of micro lymph nodes detected, rate of lymph node metastasis, and inoperative and postoperative recovery were compared. RESULTS: Of the 93 patients analyzed, 34 were in the CNSI group, 27 were in the ICG group, and 32 were in the control group. The mean number of lymph nodes retrieved in the CNSI group (48.44) was higher than that in the ICG (39.19) and control (35.28) groups (P = 0.004; P < 0.001), and there was no difference between the ICG and control groups (P = 0.102). The mean number of micro lymph nodes retrieved in the CNSI group (13.24) was higher than that in the ICG (5.74) and control (5.66) groups (P < 0.001). The lymph node metastasis rates in the CNSI, ICG, and control groups were 5.03, 4.63, and 5.93%, respectively (P > 0.05). CONCLUSION: The effect of CNSI on lymph node dissection and sorting was better than that of ICG, and CNSI improved the surgical quality and reduced lymph node staging deviation to a greater extent. CNSI was better than ICG in terms of improving the number of micro lymph nodes detected.