Risk factors and patterns of lymph node involvement in primary gastric large B-cell lymphoma: implications for target definition

BACKGROUND: The aim of this study was to identify the appropriate radiation volume for primary gastric diffuse large B-cell lymphoma (PG-DLBCL). METHODS: We retrospectively analyzed the clinical and pathological findings of 68 patients treated with total gastrectomy and D2 lymphadenectomy. RESULTS: There were 23, 14, and 29 patients with stage I, stage II, and stage IIE disease, respectively, and 30 patients had lymph node involvement. Primary tumor location, as well as the depth of invasion, was significantly associated with lymph node involvement. When the tumor was limited to the muscularis, the involved lymph nodes were found to be perigastric nodes. For tumors invading beyond the muscularis, regional lymph nodes were involved. CONCLUSION: The optimal radiation volume for patients with PG-DLBCL is largely dependent on the primary location and depth of invasion. Larger series and longer follow-up are needed to further delineate the radiation volumes for PG-DLBCL.