Lymphatic involvement in early gastric cancer - Prevalence and prognosis in France

Background: The prognosis of early gastric cancer (EGC) is considered bette r than that of invasive gastric carcinoma, with a 5-year survival rate of m ore than 90% after surgery. The prevalence of lymph node metastasis in EGC ranges from 8%, to 20% and is associated with a poor prognosis. Hypothesis: The main prognostic factor of EGC in patients in France is lymp hatic involvement. Design, Setting, and Patients: From January 1979 to December 1988, 332 pati ents with EGC were operated on in 23 centers of 2 of the French Association s for Surgical Research. Clinical, pathological, and therapeutic data were reviewed, and the reckoning point was in June 1996. Main Outcome Measures: The cumulative 5- and 7-year specific survival rates of EGC with or without lymphatic involvement. Results: The cumulative 5- and 7-year specific survival rates of 332 patien ts with EGC (mean follow-up time, 80 months), excluding both operative and unrelated mortality, were 92% and 87.5%, respectively. Thirty-four patients (10.2%); had metastatic lymphatic spread: 13 exclusively in the lymphatic vessels close to the tumor, 17 in at least 1 lymph node, and 4 in both the lymphatic vessels and nodes. The rate of lymph node involvement (regardless of lymphatic vessel involvement) correlated significantly with submucosal invasion (P=.05) and histologic undifferentiation (P=.03). Lymphatic vessel involvement correlated positively with lymph node involvement (P=.003). Si nce 5- and 7-year survival rates of the 13 patients with EGC who had lympha tic vessel involvement without lymph node involvement did not differ signif icantly from those of patients who had EGC with lymph node involvement (85% and 84% vs 72% and 63%, respectively [P=.42]), all patients with lymph nod e and/or lymphatic vessel involvement were considered unique. Prognosis was poorest in these patients according to both univariate analysis (94% for 2 98 without node or vessel involvement vs 78% for 34 with node and/or vessel involvement; P=.006) and multivariate analysis (P=.01). Submucosal invasio n was a prognostic factor independent of lymphatic involvement (P=.05). Fiv e- and 7-year survival rates did not differ when the group of 211 patients for whom less than 15 lymph nodes were retrieved were compared with those ( n=51) for whom 15 or more lymph nodes were retrieved (95.5% vs 92% and 95.5 % vs 88%, respectively), whether according to univariate (P=.21) or multiva riate (P=.31) analysis. Conclusions: Our results suggest that both lymph node and lymphatic vessel involvement are important prognostic factors in patients with EGG. Lymphade nectomy in EGC is important to identify the high-risk population for whom p rognosis is worse. The extent of lymphadenectomy (at least 15 nodes) in the se patients, however, does not alter prognosis.