Minimally invasive surgery for esophageal cancer: a review on sentinel node concept

Lymphoadenectomy is a cornerstone of esophageal cancer treatment, and sentinel node (SN) biopsy (SNB) might provide surgeons with an extra tool to limit unnecessarily extended lymphadenectomy and to implement a minimally invasive approach. The aim of our study was to review all the available literature on the use of SNB in esophageal surgery for malignancy. The review was conducted according to the PRISMA guidelines. A systematic search was performed in PubMed, EMBASE, and the Cochrane database to identify all original articles on the role of SNB in esophageal cancer. Data on methodologies, tumor stage and localization, and results were summarized and used to address relevant clinical questions related to the application of the SNB technique in esophageal cancer. Twelve studies were included, with a total of 492 patients. Different methods for SN identification were used (radionuclide, blue dye, computed tomography [CT] lymphography). The pooled values estimated using the random-effects model were, respectively: technetium-99 m overall detection rate (DR) 0.970 (95 % CI 0.814-0.996), accuracy (ACC) 0.902 (95 % CI 0.736-0.968); blue-dye DR 0.971 (95 % CI 0.890-0.993), ACC 0.790 (95 % CI 0.681-0.870); and CT lymphoscintigraphy DR 0.970 (95 % CI 0.814-0.996), ACC 0.902 (95 % CI 0.736-0.968). Based on these results, the concept of SN in esophageal cancer is technically feasible with an acceptable DR and ACC, and it might be applicable in the event of early-stage adenocarcinoma of the gastroesophageal junction in patients with a high surgical risk or in a patient where an endoscopic resection is taken into consideration. Further studies focused on a single tumor type and localizations are needed in order to predict the correct utilization of this concept in minimally invasive treatment of esophageal cancer.