Prognostic comparison of endoscopic submucosal dissection versus surgery for undifferentiated early gastric cancer: a...

Although endoscopic submucosal dissection (ESD) is widely accepted for early gastric cancer (EGC), its role in managing undifferentiated-type EGC (UD-EGC) is still debated. This multicenter study aimed to compare the short- and long-term outcomes of ESD and surgery in patients with UD-EGC.

We retrospectively analyzed patients with UD-EGC who underwent ESD or surgery at 11 tertiary centers in Taiwan between 2007 and 2025. Inclusion criteria included intramucosal tumors ≤ 20 mm without ulceration or lymphovascular invasion. Demographic, endoscopic, and pathological data were collected, and long-term outcomes were compared.

A total of 37 ESD and 42 surgery patients were analyzed. En bloc resection was achieved in all cases. R0 resection rates were 86% for ESD and 98% for surgery in unadjusted analysis (P = 0.06), while propensity score-weighted analysis showed significantly higher R0 resection in the surgery group (85.8% vs. 98.7%, P = 0.017). The ESD group demonstrated significantly shorter procedure times (84.6 vs. 285.7 min, P < 0.001) and hospital stays (6.8 vs. 17.6 days, P < 0.001). Complication rates were comparable between groups (11% for ESD vs. 14% for surgery, P = 0.74). In unadjusted analyses, the cumulative incidence of recurrence was higher in the ESD group than in the surgery group (P = 0.03), whereas overall survival (OS) was similar between groups (5-year OS: 93% for ESD vs. 90% for surgery; log-rank P = 0.12). After propensity score overlap weighting, the difference in recurrence between groups was attenuated and no longer statistically significant (P = 0.22).

Although ESD is less invasive with shorter procedure time and hospital stay, its lower R0 resection rate and higher recurrence risk require careful patient selection and close surveillance. Similar OS supports the potential role of ESD in selected UD-EGC patients, although further validation is needed.