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