Background: The optimal surgical strategy for proximal gastric cancer (PGC) remains controversial. The principal difference between total gastrectomy (TG) and proximal gastrectomy (PG) is whether lymph node (LN) 4d is dissected by radical lymphadenectomy.
Patients and methods: The subjects were 243 patients with PGC who had undergone TG between 1990 and 2006. The incidences of metastases to individual LNs were assessed. The 5-year disease-specific survival (DSS) was examined in 179 patients who had undergone TG and an additional 37 patients who had undergone PG between 1990 and 2002.
Results: When PGC was confined to the muscularis propria (mp), no patient had LN 4d or 8 metastases although these nodes are considered regional LNs, and the 5-year DSS rate did not significantly differ between TG and PG. When the PGC extended beyond the mp, the patients with LN 4d or 8 metastases in N2 disease had very poor outcomes, similar to those with N3 disease. Multivariate analysis revealed that lymph node metastatic density over 40% (ND40) was the strongest independent prognostic factor (p=0.001, HR=6.1). ND40 was significantly associated with LN 4d or 8 metastases in N2 disease (p=0.047).
Conclusion: LN 4d or 8 metastasis is equivalent to advanced LN metastasis and the presence of such metastasis indicates a poor prognosis, regardless of LN dissection, thus, PG might therefore be an adequate procedure for LN dissection in patients with PGC.