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Recurrence patterns of esophagogastric junction adenocarcinoma according to Siewert's classification after radical resection.

BACKGROUND
The treatment strategy for adenocarcinoma of the esophagogastric junction (AEG) remains controversial. In the present study, the recurrence pattern of AEGs according to Siewert's classification after radical resection was reviewed, and predictive factors of recurrence were examined.


PATIENTS AND METHODS
We retrospectively analyzed the clinical data of 127 consecutive patients with Siewert type I, II, and III AEGs who underwent curative resection (R0) without perioperative chemotherapy at the National Cancer Center Hospital East between January 1993 and November 2006.


RESULTS
The median follow-up period was 48.9 (range=1.5-179) months. The recurrence rates of type I, II, and III tumors were 57.1%, 44.4%, and 41.0%, respectively. The most frequent relapse site was lymphogenous in type I, hematogenous in type II, and disseminative in type III tumors. The median time-to-recurrence after surgery was 12.6 months in type I, 12.5 months in type II, and 12.7 months in type III disease, with no significant difference. Multivariate analysis revealed that mediastinal lymph node metastasis (p=0.005) (hazard ratio=2.954, 95% Confidence Interval=1.38-6.31) was a significant and independent prognostic indicator for poor recurrence-free survival. The recurrence rate in patients with mediastinal lymph node metastasis at the time of surgery was 100%.


CONCLUSION
The recurrence pattern of AEGs differed according to Siewert's classification. Its tendency should be understood in order to determine the optimal surgical approach. Mediastinal lymph node dissection may be effective for local control, but may not significantly improve prognosis. When mediastinal lymph node metastasis is suspected, perioperative chemotherapy may be recommended.