Long-term Outcome of Esophageal Mucosal Squamous Cell Carcinoma Without Lymphovascular Involvement After Endoscopic Resection

Background: Esophageal cancer is an aggressive cancer with a reported 3-year survival of 20%. However, early-stage esophageal cancer can be cured by endoscopic resection (ER). The long-term survival of esophageal mucosal squamous cell carcinoma after ER was investigated by calculating the standard mortality rate (SMR).

Methods: From January 1995 to December 2004, 110 patients with 138 esophageal mucosal squamous cell carcinomas without lymphovascular involvement were treated by ER. Long-term survival after ER was compared with that in the general population by calculating SMR. Subgroup analysis of patients without second primary cancer diagnosed within 1 year before ER (subgroup A) was also performed.

Results: A total of 108 patients (98.2%) were followed-up completely, with a mean observation period of 4.7 (0.4-11.3) years. The cumulative 5-year survival rate of all patients and subgroup A was 79.5% and 86.6%, respectively. Overall mortality (SMR, 1.68; 95% confidence interval [CI], 1.05-2.55) and mortality from malignant tumor (SMR, 3.14; 95% CI, 1.79-5.09) was significantly higher than that in the general population. SMR of esophageal cancer was high, although it was not significantly different from that in the general population (SMR, 4.82; 95% CI, 0.06-26.81). In subgroup A overall mortality (SMR, 0.86; 95% CI, 0.41-1.57) was similar to that in the general population.

Conclusions: High overall mortality in patients with esophageal mucosal cancer after ER was mainly due to elevated mortality from second primary cancer. Favorable mortality in subgroup A indicates the efficiency of ER as a curative treatment for esophageal mucosal cancer.