Deep impact analysis of surgical strategy changes guided by indocyanine green fluorescence angiography in laparoscopic low anterior resection for rectal cancer.

PURPOSE: This study investigated the patient factors leading to ICG fluorescence angiography (ICG-FI)-guided surgical plan changes during rectal cancer surgery and evaluated the impact of these changes on anastomotic height and postoperative bowel function. METHODS: In a retrospective analysis of 302 patients undergoing laparoscopic low anterior resection, we compared 28 patients requiring perfusion-based plan changes (Change group) to 274 without changes (No-Change group). We analyzed demographics, anastomotic height, and 6-month LARS scores. RESULTS: The Change group had significantly older age, higher BMI, more neoadjuvant therapy, and lower tumor height. Their final anastomoses were higher (8.0 vs. 6.0 cm, p < 0.001). This group also had better bowel function, with lower LARS scores (18 vs. 25, p = 0.007) and fewer major LARS cases (14.3% vs. 32.1%, p = 0.041). Anastomotic leakage rates were similar. CONCLUSIONS: ICG-FI identifies patients with perfusion risk factors (age, obesity, neoadjuvant therapy, low tumors) who benefit from surgical plan modification. Guiding the proximal resection margin based on ICG assessment to create a higher, well-perfused anastomosis significantly improves functional outcomes, underscoring its role in personalized surgery. TRIAL REGISTRATION: The study was registered in the clinical trials registry with registration number NCT06270745.