Assessment of the Relationship Between Positive Radial Margin and Prognosis in Patients with Gastric Adenocarcinoma.

: Gastrectomy is among the most effective treatments for gastric adenocarcinoma. Margin status can be categorized into three types: proximal, distal, and radial margins. While the relationship between proximal and distal margin involvement in specimens and prognosis has been extensively studied, the impact of a radial margin has not been thoroughly investigated. This study was conducted to determine whether a positive radial margin could affect the prognosis of patients with gastric adenocarcinoma undergoing gastrectomy. : This is a retrospective cohort study of patients with stage II/III gastric adenocarcinoma who received gastrectomy from January 2009 to December 2019 at Taichung Veterans General Hospital, Taiwan. The clinicopathologic features and outcomes were compared between groups. : Among the 431 patients who underwent gastrectomy, 94 patients (21.8%) had a positive margin. Radial margin positivity accounted for 16.2%. Factors associated with a positive margin included perineural invasion and advanced cancer stage. The factors related to poor overall survival (OS) and disease-free survival (DFS) included advanced Borrmann type, positive nodal disease, higher nodal burden (≥5), and margin status. In the subgroup analysis, radial margin positivity could negatively impact OS and DFS in the advanced T stage subgroup and nodal-positive subgroup. : Aggressive tumor biology may result in a positive margin following gastrectomy. A positive radial margin was correlated with poorer OS and DFS. Future investigations should focus on developing tailored treatment plans for patients with a positive radial margin.