Significance of the depth of tumor invasion and lymph node metastasis in superficially invasive (T1) esophageal adenocarcinoma

Superficially invasive esophageal adenocarcinomas are a heterogeneous group of tumors, including tumors invading into mucosa and submucosa. The prognostic significance of the depth of tumor invasion and lymph node status in this group of patients remain unclear. We evaluated 90 consecutive patients with resected T1 adenocarcinoma of esophagus or esophagogastric junction. The T1 tumors were classified into four groups based on the depth of invasion: T1a, invading into lamina propria; T1b, into muscularis mucosae; T1c, into superficial submucosa; and T1d, into deep submucosa. The depth of tumor invasion was compared with clinicopathologic features. The depth of tumor invasion was significantly associated with the presence of lymph node metastasis (36% in T1d, 8% in T1c, 12% in T1b, and 0% in T1a; P < 0.001) and with tumor size (76% > 1.2 cm in T1d, 75% in T1c, 35% in T1b, and 25% in T1a; P < 0.001). The 5-year recurrence-free and overall survivals were significantly better in patients with tumors confined to mucosa (100% and 91%, respectively) than invasive into submucosa (60% and 58%; P = 0.0005 and P = 0.02, respectively). Lymph node rnetastasis was associated with tumor recurrence (P = 0.01) but not overall survival. Lymphovascular invasion was associated with both tumor recurrence (P = 0.001) and overall survival (P < 0.001) and was an independent prognostic factor in multivariate analysis (P = 0.04). Our study indicated evaluation of depth of tumor invasion, status of lymph nodes, and lymphovascular invasion is important in resected superficially invasive esophageal adenocarinoma and may provide supportive information for the decision about postoperative adjuvant therapy.