The Role Of Indocyanine Green Fluorescence Imaging In Minimally Invasive Rectal Cancer Surgery: Tissue Perfusion And Lymph Node Mapping

BACKGROUND Despite advances in minimally invasive robotic surgery, key challenges persist— particularly in accurately staging lymphatic spread and assessing anastomotic perfusion. Real-time fluorescence-guided surgery using intraoperative indocyanine green (ICG) has gained popularity in rectal cancer procedures. This study aims to evaluate whether fluorescence imaging with ICG, can improve intraoperative identification of lymph nodes and ensure adequate anastomotic perfusion to reduce leakage risk. MATERIALS AND METHODS Between September 2020 and December 2024, 40 patients with rectal cancer underwent minimally invasive anterior rectal resection at the University Unit of General Surgery, Policlinico of Foggia. All underwent robotic or laparoscopic surgery and were divided into two groups: Group A received both preoperative peritumoral and intraoperative intravenous ICG injections; Group B did not receive ICG. RESULTS The comparative analysis between patients undergoing ICG-guided surgery (Group A) and those without ICG (Group B) showed trends favoring the ICG group, though most differences were not statistically significant. Group A had a slightly higher average number of harvested and positive lymph nodes, and intraoperative ICG fluorescence led to modified lymphadenectomy in 30% of cases and resection margin adjustments in 25%. Group A achieved 100% optimal mesorectal excision versus 75% in Group B. Notably, no anastomotic leaks occurred in Group A, compared to a 10% leak rate in Group B, suggesting a possible benefit of ICG in preventing complications. A Pearson correlation test showed no statistically significant associations, but a weak positive trend indicates that larger studies may reveal more definitive advantages of ICG- guided surgery. CONCLUSIONS This study confirms the feasibility and safety of ICG fluorescence imaging in minimally invasive rectal cancer surgery. While statistical significance was not consistently achieved, ICG use was associated with improved lymph node mapping, better mesorectal excision quality, earlier bowel recovery, and fewer anastomotic