ICG-Guided Lymphadenectomy during Surgery for Colon and Rectal Cancer—Interim Analysis of the GREENLIGHT Trial

Abstract

Lymphadenectomy is crucial for an optimal oncologic resection of colon and rectal cancers. However, without a direct visualization, an aberrant route of lymph node (LN) diffusion might remain unresected. Indocyanine-green (ICG) lymphatic mapping permits a real-time LNs visualization. We designed the GREENLIGHT trial to explore in 100 patients undergoing robotic colorectal resection the clinical significance of a D3 ICG-guided lymphadenectomy. The primary endpoint was the number of patients in whom ICG changed the extent of lymphadenectomy. We report herein the interim analysis on the first 70 patients. After endoscopic ICG injection 24 h (n = 49) or 72 h (n = 21) ahead, 19, 20, and 31 patients underwent right colectomy, left colectomy, and anterior rectal resection. The extent of lymphadenectomy changed in 35 (50%) patients, mostly (29 (41.4%)) for the identification of LNs (median two) outside the standard draining basin. Identification of such LNs was less frequent in rectal tumors that had undergone chemoradiotherapy (26.3%) (p > 0.05). A non-significant correlation between time-to-ICG injection and identification of aberrant LNs was observed (48.9% at 24 h vs. 23.8% at 72 h). The presence of LN metastases did not affect a proper fluorescent mapping. These data indicate that ICG lymphatic mapping provides relevant information in 50% of patients, thus increasing the accuracy of potentially curative resections.

The NXDC-MEN-301 Study on 5-ALA for Meningiomas Surgery: An Innovative Study Design for the Assessing the Benefit of Intra-Operative Fluorescence Imaging

“…Apart from brain tumors, efforts are underway to extend FGR to other organ systems as well, not only using 5-ALA [ 17 , 18 , 19 , 20 ], but also other fluorochromes, and study designs resulting in regulatory approval are being intensely discussed [ 21 ].…”

Indocyanine Green Fluorescence Guided Surgery in Colorectal Surgery

“…More recently, the interim analysis of the GREENLIGHT trial, [ 72 ] a prospective non-randomized trial of ICG lymphatic mapping, showed that the extent of the lymphadenectomy was modified based on the results of imaging in 50% of the study population (35/70). What was more interesting is that they demonstrated that lymph node metastasis was not correlated with a paucity in ICG signal, as was shown in previous studies.…”

A New Urokinase Plasminogen Activator Receptor‐Targeted Near‐Infrared Fluorescence (NIR) Probe for Glioma Imaging

“…Since ICG was initially applied to guide the resection of brain tumors, its application in tumor diagnosis and surgical navigation has been pursued actively. Moreover, fluorescence imaging (FLI) in the second near‐infrared window (NIR‐II) of ICG has been further investigated and utilized in recent years [5–10] …”

“…Moreover, fluorescence imaging (FLI) in the second near-infrared window (NIR-II) of ICG has been further investigated and utilized in recent years. [5][6][7][8][9][10] Despite the advantages mentioned above, the features such as passive tumor uptake and the short half-life of free ICG still limit its clinical application in accurate tumor imaging, especially the accurate identification of tumor margins in tumor operation. Therefore, developing ICG-labeled probes for tumorspecific targets will conquer the obstacles in clinical practice.…”