Surveillance strategy based on the incidence and patterns of recurrence after curative endoscopic submucosal dissection for early gastric cancer.

BACKGROUND AND STUDY AIMS: To suggest an appropriate surveillance strategy after curative endoscopic submucosal dissection (ESD) for early gastric cancers, based on incidence and patterns of local, metachronous, and extragastric recurrence. PATIENTS AND METHODS: Between 2003 and 2011, 1497 consecutive patients with 1539 differentiated-type early gastric cancers meeting absolute or expanded indication criteria underwent curative ESD. They were followed up with esophagogastroduodenoscopy (EGD) and abdominal computed tomography (CT) under a standardized surveillance protocol. Long-term outcomes were analyzed for 1306 patients with at least 1 year's follow-up. RESULTS: Incidences of residual and synchronous lesions detected within 1 year were 0.13 % and 0.87 %, respectively. During median 47 months of follow-up, there was 1 local recurrence (0.08 %; early gastric cancer) and 47 cases of metachronous recurrence (3.6 %; 44 early gastric cancers, 3 pT2 advanced gastric cancers); all were curatively treated. During a 5-year surveillance, the cumulative incidence curve of metachronous recurrence increased linearly. Median time from ESD to metachronous recurrence was 30 months. There were 2 extragastric recurrences (0.15 %) in lymph nodes, at 5 and 4 years, respectively, after curative ESD for absolute and expanded indications. The patient with the expanded indications underwent a palliative operation and died of gastric cancer progression. CONCLUSIONS: There was a constant incidence rate of metachronous recurrence during a 5-year surveillance period and there was extragastric recurrence at least 4 years after ESD of early gastric cancer even for absolute indications. Therefore, annual or biannual surveillance EGD and abdominal CT might be necessary for at least 5 years after curative ESD for early gastric cancers, with absolute as well as expanded indications.