Background/aims: The prognosis of patients with gastric adenocarcinoma varies with the location of the tumor. Adenocarcinoma in the middle third of the stomach has been claimed to have a better outcome than those in other locations. However, there is still very limited information specifically regarding the prognostic factors which influence the survival time of patients with adenocarcinoma in the middle third of the stomach. This retrospective study was designed with the aim to evaluate and uncover the possible significant clinicopathological parameters for adenocarcinoma in the middle third of the stomach.
Methodology: Between 1986 and 1992, 363 patients underwent gastric resection for primary gastric adenocarcinoma at this hospital. Fifty-two (14.3%) of these patients were included in this study and they all met the following criteria: 1) tumor primarily located in the middle third of the stomach without distant metastases or peritoneal seeding, 2) undergoing curative resection and 3) undergoing R2 nodal dissection, at least. The clinicopathological findings were obtained by detailed review of the medical records and the histologic slides. All surviving patients were also contacted and their current conditions were recorded.
Results: The overall 5-year survival rate (Kaplan-Meier method) was 42.5%. In univariate survival analysis by Kaplan-Meier method and long-rank test, serosal invasion (p < 0.01), lymph node metastasis (p < 0.01) and lymphatic involvement (p < 0.01) had an individual prognostic significance. When a multivariate analysis using Cox proportional hazards regression was performed, serosal invasion (P < 0.01) and lymphatic involvement (p < 0.05) appeared as the only two independent prognostic factors regarding long-term survival. When these 52 patients were categorized into patients with early gastric cancer (n = 10) and patients with advanced gastric cancer (n = 42), there was a significant difference (p < 0.01) between the survival rates (90.0% vs. 29.1%). When these tumors were further categorized into early gastric cancer (n = 10), early simulating advanced gastric cancer (n = 14) and Borrmann type advanced gastric cancer (n = 28), there were significant differences (P < 0.01 and P < 0.01, respectively) in 5-year overall survival rates between early gastric cancer (90.0%) and Borrmann type advanced gastric cancer (18.9%), also between early simulating advanced gastric cancer (52.5%) and Borrmann type advanced gastric cancer (18.9%). UICC stage also had significant influence (P < 0.01) on the survival rates.
Conclusions: Serosal invasion and lymphatic involvement are the significant, independent prognostic factors in predicting the survival rate of patients with adenocarcinoma in the middle third of the stomach. Since more advanced stage tumors usually carry a poorer prognosis, early detection is of extreme importance for improving the survival rate.