Distinct Differences in Gastroesophageal Junction and Gastric Adenocarcinoma in 2194 Patients

Objective: We sought to compare gastroesophageal junction (GEJ) cancer and gastric cancer (GC) and identify clinicopathological and oncological differences. Summary Background Data: GEJ cancer and GC are frequently studied together. Although the treatment approach for each often differs, clinico-pathological and oncological differences between the 2 have not been fully evaluated. Methods: We retrospectively identified patients with GEJ cancer or GC who underwent R0 resection at our center between January 2000 and December 2016. Clinicopathological characteristics, disease-specific survival (DSS), and site of first recurrence were compared. Results: In total, 2194 patients were analyzed: 1060 (48.3%) with GEJ cancer and 1134 (51.7%) with GC. Patients with GEJ cancer were younger (64 vs 66 years; P < 0.001), more often received neoadjuvant treatment (70.9% vs 30.2%; P < 0.001), and had lower pathological T and N status. Five-year DSS was 62.2% in patients with GEJ cancer and 74.6% in patients with GC (P < 0.001). After adjustment for clinicopathological factors, DSS remained worse in patients with GEJ cancer (hazard ratio, 1.78; 95% confidence interval, 1.40–2.26; P < 0.001). The cumulative incidence of recurrence was approximately 10% higher in patients with GEJ cancer (P < 0.001). The site of first recurrence was more likely to be hematogenous in patients with GEJ cancer (60.1% vs 31.4%; P < 0.001) and peritoneal in patients with GC (52.9% vs 12.5%; P < 0.001). Conclusions: GEJ adenocarcinoma is more aggressive, with a higher incidence of recurrence and worse DSS, compared with gastric adenocarcinoma. Distinct differences between GEJ cancer and GC, especially in patterns of recurrence, may affect evaluation of optimal treatment strategies.