Whole-body PET with FDG for the diagnosis of recurrent gastric cancer

• DOI: 10.1007/s00259-001-0743-8
• Publication Date: 2003-02-13T02:43:30Z
• Authors: T. De Potter; P. Flamen; E. Van Cutsem; F. Penninckx; L. Filez; G. Bormans; A. Maes; L. Mortelmans
• Keywords: Male; Databases, Factual; Adenocarcinoma; Middle Aged; Adenocarcinoma, Mucinous; Sensitivity and Specificity; Survival Analysis; 3. Good health; Radiography; 03 medical and health sciences; 0302 clinical medicine; Fluorodeoxyglucose F18; Stomach Neoplasms; Humans; False Positive Reactions; Female; Single-Blind Method; Neoplasm Recurrence, Local; Radiopharmaceuticals; Carcinoma, Signet Ring Cell; False Negative Reactions; Neoplasm Staging; Retrospective Studies

This retrospective study was designed to assess the accuracy of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) in diagnosing recurrence of gastric cancer. Thirty-three patients who had received surgical treatment for gastric cancer with curative intent and who had subsequently undergone FDG-PET for suspected recurrence were retrieved from the PET database. All patients were reviewed with full knowledge of prior conventional diagnostic work-up. Results were compared with a gold standard, consisting of histological confirmation or radiological and clinical follow-up. The gold standard established disease recurrence in 20/33 patients (prevalence 61%). Sensitivity and specificity of FDG-PET for the diagnosis of recurrence were 70% (14/20) and 69% (9/13), respectively. Positive and negative predictive values were 78% (14/18) and 60% (9/15), respectively. Of the six false-negative cases, all had intra-abdominal lesions (three had generalised abdominal metastases, one liver metastasis, one local recurrence and one ovarian metastasis). In the subgroup with previous signet cell differentiation of the primary tumour ( n=13, disease prevalence 62%), sensitivity was 62% (5/8) and specificity, 60% (3/5). Survival analysis for the entire patient group using Kaplan-Meier statistics yielded a longer survival in the PET-negative group (mean+/-SD, 21.9+/-19.0 months) than in the PET-positive group (mean+/-SD, 9.2+/-8.2 months) ( P=0.01). In the patient group with proven recurrence ( n=20), the mean survival for the PET-negative group was 18.5 (+/-12.5) months, as compared with 6.9 (+/-6.5) months for the PET-positive group ( P=0.05). Because of its poor sensitivity and low negative predictive value, FDG-PET is not suited for screening purposes in the follow-up of treated gastric cancer. However, FDG-PET appears to provide important additional information concerning the prognosis of recurrent gastric cancer.