Clinicopathologic Characteristics of and Prognosis for Proximal Gastric Carcinomas

ABSTRACT

PURPOSE: Many epidemiological studies have revealed an increasing tendency for proximal gastric cancer. Furthermore, proximal gastric cancer has been known to have unique characteristics and a poor prognosis in contrast to middle and distal gastric cancer, but the reason have not yet been fully explained. For that reason, we investigated changes in the incidence of proximal gastric cancer, its clinicopathologic characteristics, and its prognosis, and we compared the results with those of other reports and tried to identify the reasons for such phenomena. METHODS: After excluding linitis platisca-type cancer, double primary cancer, and gastric cancer arising from the remnant stomach, we retrospectively analyzed the case histories of 836 patients who had undergone operations for gastric cancer from 1992 to 1997. The cases were divided into a proximal gastric-cancer (PGC) group and a middle and distal gastric-cancer (DGC) group based on the location of the primary tumor. RESULTS: The PGC group included 74 patients (8.9%); 762 patients (91.1%) were in the DGC group. The incidence of proximal gastric cancer was 5.0% in 1992 and 11.6% in 1997. The PGC group has more advanced tumor stages (p=0.001) and more positive lymph-node metastases (p=0.013). The resectability of PGC was 87.8%, and that of the DGC was 92.4%, but these were not significantly different (p=0.169). The overall 5-year survival rate for PGC was 48.4% and that of DGC was 59.0%, but these were also not significantly different (p=0.5776). Comparing the survival rates of two groups for various stages revealed no differences. CONCLUSION: The increasing tendency of proximal gastric cancer was similar those in other reports even though we observed for a shorter periods and the proximal gastric cancers were diagnosed in advanced stages, and probably that was the reason for the poor prognosis. Therefore, if early diagnosis is made and adequate therapy is performed, proximal gastric cancer, in contrast to distal gastric cancer, is not a unique disease entity.