Background: Although gastric cancer with isolated para-aortic lymph node (PAN) involvement is considered an advanced disease, the clinical characteristics of it have not been comprehensively elucidated.
Patients and methods: We reviewed the medical records of 1,277 patients received palliative chemotherapy with advanced gastric cancer according to metastatic sites: PAN-only metastasis, single organ metastasis other than PAN, and multiple organ metastasis. Time to other organ metastasis (TTOM) was determined only in PAN-only metastasis group as the time interval between initial diagnosis of recurrence or de novo metastasis and confirming distant metastasis beyond PAN area.
Results: The median overall survival (OS) of patients with PAN-only metastasis was significantly longer than that of patients with single organ metastasis other than PAN or multiple organ metastasis (13.8 months vs. 11.4 months vs. 8.4 months; P < 0.001). In the PAN-only metastasis group, patients with recurrent diseases showed longer TTOM beyond the PAN area (10.7 vs. 7.7 months; P = 0.037) and OS (23.8 vs. 12.8 months; P = 0.010) than those with de novo metastatic disease and it was validated by multivariate analysis.
Conclusion: Patients with isolated PAN metastasis showed an excellent prognosis compared with patients with metastasis at other sites and it was primarily evident in patients with recurrent PAN metastasis.