Lymphatic mapping for upper gastrointestinal malignancies

Recent studies on lymphatic mapping of upper gastrointestinal (GI) malignancies have provided new insights with regard to the sentinel node (SN) concept in solid tumors. At present, the SN concept seems to be valid not only for breast cancer, but also for esophageal and gastric cancers, which have multidirectional and complicated lymphatic flows. In addition to the staging merits, individualized surgical management has been proposed for upper GI cancer based on the SN concept. Gastric cancer is now a suitable target of SN-guided surgery after breast cancer because of its anatomical situation. Laparoscopic local resection is theoretically feasible for curative treatment of SN-negative early gastric cancer. Because SNs in esophageal cancer are multiple and widespread, complete sampling of SNs is not a minimally invasive procedure, as it is in breast cancer. However, selective and modified lymphadenectomy targeting SNs for clinically N0 esophageal cancer instead of three-field lymph node dissection should become not only feasible but also clinically important. When performing chemoradiotherapy as curative treatment for cT1N0 esophageal cancer, lymphoscintigrams revealing the distribution of SNs in each individual case are useful to tailor the field of irradiation to control occult micrometastases. Although there are several issues to be resolved, this novel procedure has the potential to improve quality control in upper GI cancer.