Abstract
BACKGROUND: Treatment choices for patients with pathological muscularis mucosa/submucosal layer (pMM/SM1) esophageal squamous cell cancer (ESCC) after endoscopic resection (ER) are controversial. MATERIALS AND METHODS: A single-center retrospective study at Beijing Cancer Hospital in China was conducted. Between February 2012 and November 2023, we retrospectively recruited patients with pMM/SM1 ESCC who underwent ER with or without subsequent adjuvant therapy. Survival was compared between groups. RESULTS: Overall, 93 patients were screened, and 73 patients were included. Kaplan‒Meier analysis revealed that a length of invasive cancer ≤ 10 mm (OS, P = 0.025; DFS, P = 0.059) was a high-risk factor. Compared with the follow-up group, patients who underwent radical surgery (SR) immediately after ER demonstrated significantly shorter overall survival (OS) and disease-free survival (DFS) (OS, P < 0.01; DFS, P < 0.001). High-risk patients (pMM/SM1 patients with an invasive cancer length ≤ 10 mm) may benefit from chemoradiotherapy (CRT), but low-risk patients may not. CONCLUSION: The length of invasive cancer ≤ 10 mm may be a newly identified high-risk factor. CRT after ER is recommended for high-risk patients but not for low-risk patients. SR is not recommended for any patient.