Gastric Cancer
Copyright ©2008 The WJG Press and Baishidengs. All rights reserved.
World J Gastroenterol. Aug 7, 2008; 14(29): 4627-4632
Published online Aug 7, 2008. doi: 10.3748/wjg.14.4627
Clinical role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in post-operative follow up of gastric cancer: Initial results
Long Sun, Xin-Hui Su, Yong-Song Guan, Wei-Ming Pan, Zuo-Ming Luo, Ji-Hong Wei, Hua Wu
Long Sun, Xin-Hui Su, Wei-Ming Pan, Zuo-Ming Luo, Ji-Hong Wei, Hua Wu, Minnan PET Center and Department of Nuclear Medicine, the First Hospital of Xiamen, Fujian Medical University, Xiamen 316003, Fujian Province, China
Yong-Song Guan, State Key Laboratory of Biotherapy, West China Medical School, Sichuan University, Gaopeng Street, Keyuan Road 4, Chengdu 610041, Sichuan Province, China
Author contributions: Sun L and Su XH contributed equally to the paper; Pan WM, Luo ZM and Wei JH completed patient follow-ups and data collection; Guan YS helped to write, organize, and correct the paper; Wu H supervised the writing and organization process.
Correspondence to: Hua Wu, Minnan PET Center and Department of Nuclear Medicine, the First Hospital of Xiamen, Fujian Medical University, Xiamen 316003, Fujian Province, China. wuhua1025@163.com
Telephone: +86-592-2139527
Fax: +86-592-2139527
Received: May 23, 2008
Revised: June 30, 2008
Accepted: July 7, 2008
Published online: August 7, 2008
Abstract

AIM: To evaluate the clinical role of 18F-fluorodeo-xyglucose positron emission and computed tomography (18F-FDG PET/CT) in detection of gastric cancer recurrence after initial surgical resection.

METHODS: In the period from January 2007 to May 2008, 23 patients who had previous surgical resection of histopathologically diagnosed gastric cancer underwent a total of 25 18F-FDG PET/CT scans as follow-up visits in our center. The standard of reference for tumor recurrence consisted of histopathologic confirmation or clinical follow-up information for at least 5 mo after PET/CT examinations.

RESULTS: PET/CT was positive in 14 patients (61%) and negative in 9 (39%). When correlated with final diagnosis, which was confirmed by histopathologic evidence of tumor recurrence in 8 of the 23 patients (35%) and by clinical follow-up in 15 (65%), PET/CT was true positive in 12 patients, false positive in 2, true negative in 8 and false negative in 2. Overall, the accuracy of PET/CT was 82.6%, the negative predictive value (NPV) was 77.7%, and the positive predictive value (PPV) was 85.7%. The 2 false positive PET/CT findings were actually chronic inflammatory tissue lesions. For the two patients with false negative PET/CT, the final diagnosis was recurrence of mucinous adenocarcinoma in the anastomosis in one patient and abdominal wall metastasis in the other. Importantly, PET/CT revealed true-positive findings in 11 (47.8%) patients who had negative or no definite findings by CT. PET/CT revealed extra-abdominal metastases in 7 patients and additional esophageal carcinoma in one patient. Clinical treatment decisions were changed in 7 (30.4%) patients after introducing PET/CT into their conventional post-operative follow-up program.

CONCLUSION: Whole body 18F-FDG PET/CT was highly effective in discriminating true recurrence in post-operative patients with gastric cancer and had important impacts on clinical decisions in a considerable portion of patients.

Keywords: 18F-fluorodeoxyglucose; Positron emission tomography/computed tomography; Gastric cancer; Follow-up; Recurrence