Near-infrared fluorescent guided surgery in patients with pancreatic cancer

Background: The irradical resection rate of pancreatic cancer (PC) worldwide is still ∼60% due to difficulties in discriminating tumor from normal tissue. Near-infrared fluorescence (NIRF) is a promising imaging technique, potentially improving intraoperative demarcation of PC and radical resection rates. In this study, a novel, fluorescent-labelled antibody targeting carcinoembryonic antigen (CEA), named SGM-101, was investigated. The tolerability and feasibility of intraoperative fluorescence tumor imaging using SGM-101 was assessed in patients undergoing a surgical exploration for pancreatic cancer. Methods: Patients (n = 12) were injected intravenously with 5, 7.5 or 10 mg SGM-101, 48, 72 or 96 hours prior to surgery. Tolerability assessment was performed at regular intervals after dosing. During surgery the Quest NIR imaging system was used to detect the fluorescent signals. The fluorescent signals of the resected specimens were correlated to the histopathological assessment. Results: SGM-101 specifically accumulated in primary tumors, peritoneal and liver metastases, with upregulated expression of CEA, allowing real-time intraoperative fluorescence imaging. Sufficient fluorescent signals were observed in primary tumors and in metastatic lesions. Of the resected lesions, one lesion was histologically assessed as benign but was fluorescent, two lesions were histologically assessed as malign but no fluorescent signal was detected. Conclusion: Our study demonstrates that SGM-101, a safe fluorescent-labelled anti-CEA antibody, is able to penetrate PC and allows intraoperative NIRF imaging. Both primary tumors and the metastases were intraoperatively detected. The current technique should be further improved to ib=increase tumor specific fluorescent signals and sensitivity.