Deborah S Keller, MS, MD1,2, Heman M Joshi, MBChB, MRCS2, Laurence Devoto, MBBS, MSc, MRCS2, Richard Cohen, MD, FRCS2, Manish Chand, MBA, FRCS, PhD2. 1Columbia University Medical Center, 2University College London Hospitals, NHS Trusts
Background: Surgical specimens for resected colon cancer vary in quality and there remains no universally accepted technique to guide resection margins. A minimum of 12 lymph nodes provides some quality assurance, however this remains a crude marker of optimal oncological surgery. A tool to precisely identify lymphatic drainage within the mesentery could improve the oncologic quality of resection and better guide adjuvant treatment through more optimal mesenteric lymphadenectomy. While fluorescence imaging (FI) has been described to identify nodal disease in several other cancers, feasibility and best practices have not been established in colon cancer. We describe a novel technique of FI using Indocyanine Green (ICG) to identify lymphatic spread and potentially guide optimal mesenteric lymphadenectomy in colon cancer.
Methods: Three consecutive patients with colon cancer undergoing a laparoscopic resection had peritumoral subserosal injection of ICG for FI after extracorporealization of the mobilized specimen. Three concentrations of ICG were injected – 5mg/10mL, 5mg/5mL, and 5mg/3mL. A total of 4mL was given for each patient. Using a modified laparoscopic camera, the ICG was excited by light in the near-infrared (NIR) spectrum, for real-time visualization of the lymphatic drainage. The main outcome measure was identification of lymphatic drainage.
Results: Three patients with right-sided primary colon cancer were evaluated. All three patients had successful identification of the lymphatic drainage pattern along the mesentery. The most successful protocol was 1mL (concentration 5mg/10mL) subserosal injection at 4 points within close proximity (1cm) of the tumor with a 23-gauge needle, then waiting 5 minutes for complete mapping. No intraoperative or injection-related adverse effects occurred with 30-day follow-up. The median lymph node yield was 31. All specimens had tumor-free margins.
Conclusion: From this small series, fluorescence imaging with ICG is a potentially safe and feasible technique for identifying mesocolic lymphatic drainage patterns. This proof of concept and protocol will lead to future studies to examine the utility of fluoresence imaging to guide more precise surgery in colon cancer.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 85077
Program Number: P260
Presentation Session: iPoster Session (Non CME)
Presentation Type: Poster