Characteristics and clinical outcome of proximal-third gastric cancer

It is generally accepted that the prognosis of patients with proximal gastric cancer (PGC) is worse than that of patients with more distal gastric cancer.

The aim of this study was to compare the clinical features and outcomes of PGC with those of middle- and distal-third gastric cancers. A total of 646 primary gastric cancers was analyzed as a retrospective study.

Proximal gastric cancer occurred in 21.8% of the 646 cancers analyzed, and approximately 21% of PGCs had esophageal invasion. The 5-year survival rate for patients with PGC was significantly lower than that of patients with more distal tumors. When the PGC group was divided into patients with esophageal invasion and without esophageal invasion, patients with esophageal invasion had significantly worse outcomes. When corrected for depth of invasion, lesions with esophageal invasion had significantly worse outcomes than those of other sites in T2 curative cancers. Proximal gastric cancer with esophageal invasion was characterized by a larger tumor, deeper penetration, and a higher incidence of lymph node metastasis compared with tumors in other sites, and in multivariate analysis of all curative cases, these variables were independent prognostic factors for survival. The frequency of positive proximal margins of PGC was higher than those of other sites.

The relatively poor prognosis associated with PGC is mainly from advanced tumor stages of esophageal invasion. Early detection is the most important strategy to improve the survival of patients with PGC. In addition, aggressive lymph node dissection and chemotherapy for esophageal invasion should be considered even if the tumor invasion is moderate (T2 tumor), and a tumor-free margin is important.