FEASIBILITY OF SENTINEL NODE NAVIGATED SURGERY IN PATIENTS WITH HIGH-RISK SUBMUCOSAL (T1B) ESOPHAGEAL ADENOCARCINOMA USING A HYBRID TRACER OF TECHNETIUM-99M AND INDOCYANINE GREEN

Aims Minimally invasive esophagectomy with two-field thoracolaparoscopic lymphadenectomy is the current standard of care for high-risk T1b esophageal adenocarcinoma. However, since the tumor can often be removed completely with endoscopic resection, and lymph node involvement only concerns the minority of patients, the majority of patients receive overtreatment. Sentinel node navigation surgery is a well-known concept to tailor the extent of lymphadenectomy. The aim of this study was to evaluate the feasibility and safety of sentinel node navigation surgery with a hybrid tracer (technetium-99m/indocyanine green/nanocolloid) for patients with high-risk T1b esophageal adenocarcinoma.

Methods In this prospective, multicenter pilot study, five patients with high-risk T1b esophageal adenocarcinoma without neoadjuvant treatment were included. The hybrid tracer was injected endoscopically the day before surgery, followed by preoperative imaging (lymphoscintigraphy/SPECT-CT). During surgery, sentinel nodes were localized and resected based on preoperative imaging, combined with intraoperative gammaprobe- and near-infrared detection. Immediately thereafter, standard of care minimally invasive esophagectomy was performed in all patients. Primary endpoints were the percentage of patients with detectable sentinel nodes, concordance between preoperative and intraoperative sentinel node detection, and the additive value of indocyanine green.

Results Sentinel nodes could be identified and resected in all five patients, with a median of 3 sentinel nodes (range 2-7) per patient. The concordance between preoperative imaging, and intraoperative gammaprobe- and fluorescence-based detection of sentinel nodes was high. In 2 patients additional peritumoral sentinel nodes were identified with the near-infrared camera. None of the resected lymph nodes showed signs of (micro) metastases.

Conclusions Sentinel node navigation surgery using technetium-99m and indocyanine green seems feasible and safe in patients with high-risk T1b esophageal adenocarcinoma. Indocyanine green seems to be of additive value for detection of peritumoral sentinel nodes. More research is needed before introducing this new treatment algorithm in clinical daily practice.