Significance of three-field lymphadenectomy for carcinoma of the thoracic esophagus based on depth of tumor infiltration, lymph nodal involvement and survival rate.

BACKGROUND: Significance of three-field lymhpadenectomy for carcinoma of the thoracic esophagus was examined retrospectively based on depth of tumor infiltration, lymph nodal involvements and long-term survival.
METHODS: One hundred and fifty-two consecutive patients who underwent curative esophagectomy for thoracic carcinoma invading to submucosa (pT1) or deeper layers of the esophageal wall from 1983 to 1996 were examined. Sixty-six patients underwent three-field lymphadenectomy (3F) and 86 underwent two-field lymphadenectomy (2F). Survival curves were compared between 3F and 2F after stratifications according to depth of tumor infiltration, the number of positive nodes (0, 1 to 4, 5 or more), and positive intrathoracic recurrent nerve-chain nodes.
RESULTS: Overall 5-year survival rate for 3F was 43.8%, while it was 30.2% for 2F (p = 0.07). In 41 patients with pT1 cancers, the 5-year survival rate for 3F was 55.7%, while it was 41.4% for 2F (p = NS). In patients with cancers invading to muscularis propria (pT2), the 5-year survival rate for 3F was 49.4%, while it was 30.7% for 2F (p = 0.06). In patients with tumors invading to adventitia, there was no significant difference. In patients with one to four positive nodes, the 5-year survival rates for 3F was 50.1%, while it was 24.1% for 2F (p = 0.01). There was no significant difference in the subgroups with no positive nodes and five or more. In subgroups with positive recurrent nerve-chain nodes, the 5-year survival rate for 3F was 27.9%, while it was 0% for 2F (p = 0.01).
CONCLUSIONS: Significance of three-field lymphadenectomy was found in patients with one to four positive nodes or positive intrathoracic recurrent nerve-chain nodes.