Background: The aim of this study was to determine the feasibility and accuracy of sentinel lymph node (SLN) biopsy for oesophageal adenocarcinoma.
Methods: Fifty-seven patients with adenocarcinoma of the lower oesophagus (n = 40) or gastric cardia (n = 17) underwent endoscopic peritumoral injection of (99m)Tc-radiolabelled nanocolloid before en bloc resection with extended lymphadenectomy. SLNs were identified during surgery using a handheld gamma probe and the pattern of radioactive uptake was quantified after operation. All 1667 resected lymph nodes were examined immunohistochemically for micrometastases.
Results: SLNs were identified in all 57 patients. They contained metastases (n = 32) or micrometastases (n = 3) in 35 of 37 node-positive patients and there were two false-negative studies. The overall accuracy of SLN biopsy was 96 per cent and SLNs were more likely to contain tumour than other lymph nodes (P < 0.001). Tumour-infiltrated nodal stations had a higher proportion of radioactive uptake (P < 0.001). Lower oesophageal tumours had a greater proportion of SLNs (P = 0.018), radioactive uptake (P < 0.001) and malignant nodes (P = 0.004) in the mediastinum than gastric cardia tumours.
Conclusion: The sentinel node concept is applicable to oesophageal adenocarcinoma and could be used to tailor the extent of lymphadenectomy. There is a close relationship between patterns of radioactive uptake and lymphatic tumour dissemination, which differ for lower oesophageal and gastric cardia tumours.