Introduction: Sentinel node detection has become an integral part in the lymph node involvement diagnosis of several cancer entities. In esophageal and gastric carcinomas a combination of radionucleotid markers and blue dye detection has been used in the past. It would be much more easy to detect sentinel nodes by blue dye only which is the aim of this study.Patients and Methods: Forty patients with early or locally advanced carcinomas of the esophagus or stomach received a peritumoral injection endoscopically of patent blue during the operation. The visible blue node was harvested seperatelyand send for pathohistology.Results: In all 40 cases a blue stained node could be identified. In patients with adenocarcinoma of the esophagus or stomach the staining corresponded to the overall lymph node involvement in all cases of early disease (T1 tumors) and in 65% of the locally advanced tumors. This was in contrast to squamous cell carcinoma of the esophagus where sentinel node detection was possible in only 40% of the cases.Conclusion: Sentinel node detection by blue dye only is feasible and results in a similar accuracy as compared to combined detection (nucleotid and blue dye) reported in the literature. In squamous cell cancer skip metastases seem to be frequent.