title: Early Gastric Cancers: Is CT Surveillance Necessary after Curative Endoscopic Submucosal Resection for Cancers That Meet the Expanded Criteria?
abstract: Purpose To determine the yield of follow-up abdominopelvic computed tomography (CT) in detecting extragastric recurrence after curative endoscopic submucosal dissection (ESD) for early gastric cancers (EGCs) that meet the expanded criteria. Materials and Methods Institutional review board approval was obtained for this retrospective study, and the requirement to obtain informed consent was waived. Patients who underwent curative ESD for EGCs that met the expanded criteria between November 2005 and December 2009 and who underwent post-ESD CT and endoscopy were included. The final cohort comprised 415 EGCs in 404 patients (261 EGCs in 251 patients met the conventional criteria, and 154 EGCs in 153 patients met the expanded criteria). The primary outcome was post-ESD CT discovery of extragastric recurrence (ie, lymph node or distant metastasis) not detected with endoscopy. The mean radiation dose from each CT examination was calculated. The incidence of gastric recurrence detected with endoscopy and/or CT was also analyzed. The cumulative incidence of gastric recurrence during the post-ESD follow-up period was analyzed with the Kaplan-Meier method. Results From a total of 2182 post-ESD CT examinations, extragastric recurrence (lymph node metastasis) was detected in only two patients (one with EGC that met conventional criteria and one with EGC that met expanded criteria). The mean (±standard deviation) volume CT dose index, dose-length product, and size-specific dose estimate per CT examination was 28.95 mGy ± 8.44, 876.80 mGy · cm ± 161.86, and 43.78 mGy ± 11.54, respectively. From a total of 3262 post-ESD endoscopic examinations, 41 gastric recurrences were detected (11 local recurrences and five synchronous and 25 metachronous gastric cancers). Among them, eight gastric recurrences were also detected with CT. The cumulative incidences of gastric recurrence 1, 3, and 5 years after ESD were 1.7% (two of 404 patients), 3.2% (13 of 404 patients), and 7.4% (30 of 404 patients), respectively. Conclusion When EGC meets the expanded criteria, surveillance CT after curative ESD rarely depicts extragastric recurrence during 5-year post-ESD follow-up.©RSNA, 2016 Online supplemental material is available for this article.
authors.affiliation: From the Departments of Radiology (K.S.C., S.H.K., J.K.H.) and Internal Medicine (S.G.K.), Seoul National University Hospital, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea; Department of Radiology, Seoul National University College of Medicine, Seoul, Korea (S.H.K., J.K.H.); and Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea (J.K.H.).
authors.forename: Kyu Sung
authors.initials: KS
authors.lastname: Choi
authors.affiliation: From the Departments of Radiology (K.S.C., S.H.K., J.K.H.) and Internal Medicine (S.G.K.), Seoul National University Hospital, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea; Department of Radiology, Seoul National University College of Medicine, Seoul, Korea (S.H.K., J.K.H.); and Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea (J.K.H.).
authors.forename: Se Hyung
authors.initials: SH
authors.lastname: Kim
authors.affiliation: From the Departments of Radiology (K.S.C., S.H.K., J.K.H.) and Internal Medicine (S.G.K.), Seoul National University Hospital, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea; Department of Radiology, Seoul National University College of Medicine, Seoul, Korea (S.H.K., J.K.H.); and Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea (J.K.H.).
authors.forename: Sang Gyun
authors.initials: SG
authors.lastname: Kim
authors.affiliation: From the Departments of Radiology (K.S.C., S.H.K., J.K.H.) and Internal Medicine (S.G.K.), Seoul National University Hospital, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea; Department of Radiology, Seoul National University College of Medicine, Seoul, Korea (S.H.K., J.K.H.); and Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea (J.K.H.).
authors.forename: Joon Koo
authors.initials: JK
authors.lastname: Han
mesh_terms: D000368:Aged; D005260:Female; D005773:Gastroscopy; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging* / Q000473:pathology*; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome