Scheduled endoscopic surveillance controls secondary cancer after curative endoscopic resection for early gastric cancer: a multicentre retrospective cohort study by Osaka University ESD study group.
BACKGROUND
After endoscopic submucosal dissection (ESD) of early gastric cancer (EGC), patients are at high risk for synchronous or metachronous multiple gastric cancers.


OBJECTIVE
To elucidate the time at which multiple cancers develop and to determine whether scheduled endoscopic surveillance might control their development.


METHODS
A multicentre retrospective cohort study from 12 hospitals was conducted. Patients with EGC who underwent ESD with en bloc margin-negative curative resection were included. Synchronous cancer was classified as concomitant cancer or missed cancer. The cumulative incidence of metachronous cancers and overall survival rate were calculated using the Kaplan-Meier method.


RESULTS
From April 1999 to December 2010, 1258 patients met the inclusion criteria. Synchronous or metachronous multiple cancers were detected in 175 patients (13.9%) during a mean of 26.8 months. Among the 110 synchronous cancers, 21 were missed at the time of the initial ESD. Many of the missed lesions existed in the upper third of the stomach and the miss rate was associated with the endoscopist's inexperience (<500 oesophagogastroduodenoscopy cases). The cumulative incidence of metachronous cancers increased linearly and the mean annual incidence rate was 3.5%. The incidence rate did not differ between patients with or without Helicobacter pylori eradication. Four lesions (0.32%) were detected as massively invading cancers during the follow-up.


CONCLUSIONS
Nineteen per cent of synchronous cancers were not detected until the initial ESD. The incidence rate of metachronous cancer after ESD was constant. Scheduled endoscopic surveillance showed that almost all recurrent lesions were treatable by endoscopic resection.
Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
Motohiko
M
Kato
Tsutomu
T
Nishida
Katsumi
K
Yamamoto
Shiro
S
Hayashi
Shinji
S
Kitamura
Takamasa
T
Yabuta
Toshiyuki
T
Yoshio
Takeshi
T
Nakamura
Masato
M
Komori
Naoki
N
Kawai
Akihiro
A
Nishihara
Fumihiko
F
Nakanishi
Masanori
M
Nakahara
Hideharu
H
Ogiyama
Kazuo
K
Kinoshita
Takuya
T
Yamada
Hideki
H
Iijima
Masahiko
M
Tsujii
Tetsuo
T
Takehara
D000368:Aged; D002983:Clinical Competence; D003951:Diagnostic Errors / Q000706:statistics & numerical data; D004210:Dissection / Q000379:methods; D005260:Female; D005773:Gastroscopy / Q000379:methods*; D016481:Helicobacter Infections / Q000150:complications / Q000453:epidemiology; D016480:Helicobacter pylori; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D053208:Kaplan-Meier Estimate; D008297:Male; D009361:Neoplasm Invasiveness; D009378:Neoplasms, Multiple Primary / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D011159:Population Surveillance / Q000379:methods*; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000453:epidemiology / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome