Mediastinal lymph node metastasis and recurrence in adenocarcinoma of the esophagogastric junction.

Background. Whether thorough mediastinal dissection is indicated in patients with Siewert type II adenocarcinoma of the esophagogastric junction (EGJ) remains controversial. We conducted a multicenter study to find a preoperative indicator of mediastinal node metastasis. Methods. We retrospectively collected data on 315 patients with pT2-T4 Siewert type II tumors who underwent R0 or R1 resection. The rates of metastasis or recurrence were investigated for the upper, middle, and lower mediastinal lymph nodes. Multivariate logistic analysis was used to identify significant indicators of metastasis or recurrence in the mediastinal nodes. Results. The overall rates of metastasis or recurrence in the upper, middle, and lower mediastinal lymph nodes were 4 %, 7%, and 11%, respectively. Rates were significantly higher when the distance from the EGJ to the proximal edge of primary tumor was >3 cm for the upper and middle mediastinal nodes and >2 cm for the lower mediastinal nodes. Multivariate analysis revealed that this distance was the only factor significantly associated with metastasis or recurrence in any mediastinal region. The 5-year overall survival rate in the 12 patients with metastasis in the upper or middle mediastinal lymph nodes was 17%. Conclusion. The distance from the EGJ to the proximal edge of primary tumor may be a significant indicator of metastasis or recurrence in the mediastinal lymph nodes in patients with Siewert type II tumors. Thorough mediastinal lymph node dissection via a transthoracic approach may provide a therapeutic benefit when the distance is >3 cm.