PS01.156: THE PATTERN OF LYMPH NODE METASTATIC AND ITS CLINICAL SIGNIFICANCE FOR THORACIC SUPERFICIAL ESOPHAGEAL SQUAMOUS CELL CARCINOMATHE PATTERN OF LYMPH NODE METASTATIC AND ITS CLINICAL SIGNIFICANCE FOR THORACIC SUPERFICIAL ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Abstract

Abstract Background The pattern of lymph node metastasis and surgical method in superficial esophageal squamous cell carcinoma (sESCC) remains to be established. Methods Clinical data of all patients from 2003 to 2015 who underwent curative esophagectomy for thoracic sESCC were collected based on a prospectively-maintained database. The pattern of lymph node metastasis was analyzed based on depth of tumor invasion and tumor location. Results The involved lymph node region was associated to the tumor location, however, upper mediastinal and perigastric region was the most vulnerable region. As for the depth of tumor invasion, the incidence of lymph node metastasis increased with the depth of tumor invasion going deeper. No lymph node involvement was found in tumors invading proper mucosa (M2), while the distribution of positive lymph nodes in tumors invading the deepest 1/3 submucosa was similar to that in advanced ESCC. Lymphatic invasion, tumor location and upper mediastinal lymph node involvement were independent predictors for cervical lymph node metastasis. For patients without lymphatic invasion, the positive predictive value of upper mediastinal lymph node metastasis for positive cervical lymph node was low (0∼25%), while the negative predictive value was very high, wherever the tumor located (93.8∼100%). Conclusion Tumors invading till proper mucosa was the best indication for endoscopic mucosa resection; Tumors invading the deepest 1/3 submucosa might benefit from neoadjuvant therapy; Mediastinal-abdominal lymphadenectomy was essential for sESCC. For those without lymphatic invasion, cervical lymphadenectomy might be avoided in case of negative upper mediastinal lymph node. Disclosure All authors have declared no conflicts of interest.