Perioperative and recurrence-free survival outcomes after laparoscopic hepatectomy for colorectal cancer liver metastases using indocyanine green fluorescence imaging: an inverse probability treatment weighted analysis

Background: Colorectal cancer (CRC) frequently metastasizes to the liver, significantly worsening patient outcomes. While hepatectomy offers the best curative option for colorectal liver metastases (CRLM), margin recurrence remains a major challenge post-surgery. Intraoperative ultrasound (IOUS) aids tumor identification and margin determination, but its limitations in laparoscopic surgery necessitate additional methods. Indocyanine green fluorescence imaging (ICGFI) has emerged as a promising tool for tumor localization and margin assessment in CRLM. However, existing studies lack large cohorts and long-term outcomes. This study evaluates perioperative and long-term results of ICGFI-assisted laparoscopic hepatectomy in CRLM patients.

Method: A retrospective cohort study was performed on CRLM patients who underwent liver resection at our single center. The study population was divided into three groups: the L-ICG group (laparoscopic hepatectomy with ICGFI), the L-Non-ICG group (laparoscopic hepatectomy without ICGFI), and the open group (open liver resection). Robust statistical methods including multiple imputations and inverse probability of treatment weighting (IPTW) were employed to minimize bias.

Results: A total of 340 CRLM patients who underwent hepatectomy were analyzed. The L-ICG group had a higher rate of neoadjuvant therapy and smaller tumor sizes compared to the open group. The L-ICG group also demonstrated shorter operative times, less blood loss, and a higher microscopically margin-negative (R0) resection rate than other two groups. Recurrence occurred in 70% of patients, with 77% being intrahepatic. Margin recurrence was significantly lower in the L-ICG group compared to the L-Non-ICG group (15.3% vs. 45.7%, p = 0.001). Median recurrence-free survival and overall survival did not differ significantly among groups after IPTW adjustment.

Conclusion: ICGFI improves R0 resection rates, perioperative outcomes, and reduces margin recurrence in CRLM patients undergoing laparoscopic hepatectomy, though it does not significantly impact OS or RFS.