Therapeutic strategies following endoscopic submucosal dissection for T1a-MM/T1b-SM1 esophageal squamous cell carcinoma: comparisons of long-term outcomes with propensity score-matched analysis.

BACKGROUND: For esophageal squamous cell carcinoma (ESCC) invading the muscularis mucosa (T1a-MM) or upper submucosa (T1b-SM1, up to 200 µm), the curative effectiveness of endoscopic submucosal dissection (ESD) and additional therapeutic strategies remain controversial. The present study aims to investigate the effectiveness of ESD followed by different therapeutic strategies in treating such patients. METHODS: A total of 242 patients with T1a-MM/T1b-SM1 ESCCs were involved. Data on therapeutic outcomes and long-term survivals were collected for analysis. Propensity score-matched analysis was performed to compensate for selection bias between patients with no additional therapy (NAT group) and those with additional therapy (AT group). RESULTS: R0 resection rate was 83.1% and curative resection rate was 78.5%. After a mean follow-up period of 57.8 ± 27.3 months, the cumulative recurrence rate was 7.9%. The 5-year overall survival (OS) and cause-specific survival (CSS) rate was 91.1% and 94.0%. In a matched cohort of 24 pairs, the 5-year OS and CSS rates showed no significant difference between NAT group (82.0% and 87.1%) and AT group (86.0% and 89.9%) (P > 0.05). In the subgroup of patients with noncurative ESD (n = 52), the 5-year OS and CSS rates were significantly higher in surgery group (90.2% and 95.2%) than that in NAT group (50.1% and 59.5%) and chemoradiotherapy group (51.4% and 60.0%) (P < 0.05). CONCLUSIONS: ESD with no additional therapy could achieve favorable long-term outcomes in treating T1a-MM/T1b-SM1 ESCCs. For patients with noncurative ESD, surgery ranks a prime recommendation over CRT.