Objective To analyze the relationship between No.12a lymph node metastasis and clinicopathological features of upper gastric cancer and to discuss the indications and prognostic significance of lymph node dissection in this group.

Methods A retrospective analysis was performed on the medical records of 377 patients with upper gastric cancer, to compare the relationship between No.12a lymph node metastasis and clinicopathological characteristics of patients with upper gastric cancer. Kaplan-Meier method was used to analyze the prognosis of patients with or without No.12a lymph node metastasis, and Cox regression analysis was performed to analyze the influencing factors of prognosis and survival of patients with upper gastric cancer.

Results Tumor location (lesser curvature side), tumor diameter (≥5.5 cm), degree of differentiation, and T/N/TNM stage were significantly correlated with No.12a lymph node metastasis (P < 0.05). After excluding N staging, Cox regression results showed that the degree of differentiation (HR: 0.668, 95%CI: 0.48-0.931, P=0.017) and pTNM stage (HR: 6.319, 95%CI: 4.063-9.828, P < 0.001) were the independent risk factors, but No.12a lymph node metastasis (HR: 1.477, 95%CI: 0.71-3.075, P=0.297) was not an independent risk factor for survival of upper gastric cancer patients.

Conclusion No.12a lymph node metastasis does not seem to be an independent risk factor for the prognosis of upper gastric cancer patients. However, the prognosis of patients with No.12a lymph node metastasis is worse than that of patients without No.12a lymph node metastasis. The No.12a lymph nodes should be actively dissected when the tumor is in the following situations: the tumor is located in the lesser curvature, the degree of differentiation is poorly differentiated, and the tumor stage is late (T4, N3, or Ⅱ-Ⅲ stage).