Indocyanine green fluorescence angiography in laparoscopic sigmoid and rectal cancer surgery: no reduction in anastomotic leakage but a lower incidence of anastomotic strictures. A prospective single-center study.

Introduction: Anastomotic leakage (AL) remains one of the most serious complications after colorectal cancer surgery and is closely linked to postoperative morbidity and poorer oncologic outcomes. Intraoperative indocyanine green fluorescence angiography (ICG-FA) has been introduced to allow real-time assessment of bowel perfusion; however, its role in reducing AL is still debated. Therefore, the primary aim of this study was to evaluate whether intraoperative ICG-FA, compared with standard visual assessment, reduces the rate of anastomotic leakage in patients undergoing laparoscopic sigmoid or rectal cancer resection. The secondary aims were to assess its impact on the incidence of anastomotic strictures, overall postoperative complications, reoperation rates, length of hospital stay, readmission, and 30-day mortality. Methods: We conducted a prospective single-center study with a retrospective historical control group, including consecutive patients undergoing laparoscopic sigmoid or rectal cancer resection. Patients who underwent intraoperative ICG-FA between October 2023 and January 2025 were compared with those undergoing similar procedures without fluorescence assessment. The primary endpoint was AL within 30 days. Secondary outcomes included anastomotic stricture within six months, postoperative complications, reoperation, length of hospital stay, readmission, and mortality. Results: A total of 113 patients were analyzed, including 34 in the ICG-FA group and 79 in the control group. The AL rate did not differ significantly between groups (14.7% vs. 12.7%, Conclusion: Intraoperative ICG-FA did not significantly reduce the rate of AL but was associated with a lower incidence of anastomotic strictures. These results imply that fluorescence-guided perfusion assessment may help improve anastomotic healing beyond just preventing clinically evident leakage. Larger prospective multicenter studies are needed to verify these findings. Clinical trial registration: https://clinicaltrials.gov/study/NCT07423130, ClinicalTrials.gov NCT07423130.