• In a study of 540 patients with pt1a-muscularis mucosa esophageal squamous cell carcinoma, 485 were monitored without intervention.
• The 5-year cumulative recurrence rates were low at 4.9% for observation, 2.2% for chemoradiotherapy, and 10.0% for surgery.

Given the data, observation may be a viable strategy for these patients.

• Overall survival rates were high, reaching 100% for those undergoing surgery.