Abstract: Abstract: Objective To investigate the diagnostic value of 18 F - fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) in uterine cervix squamous cell cancer patients with squamous cell carcinoma antigen （SCC-Ag） elevation after treatment. Methods Data of 52 cervical squamous cancer patients with elevated SCC-Ag (>1.5 μg/L) after surgery and/or radiotherapy and chemotherapy were retrospectively analyzed．18 F-FDG PET/CT was used for full body scanning to show the recurrence and / or metastasis in patients. The diagnostic efficiency of PET / CT in the recurrence and/or metastasis of cervical squamous cell carcinoma was evaluated according to pathological and (or) follow-up results. The follow-up period was 6 to 12 months. Results There were positive 18 F-FDG PET/CT findings in 44 patients and negative 18 F-FDG PET/CT findings in 8 patients. There were 3 false-positive and 1 false-negative cases. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of diagnostic efficiency of PET/CT were 97.6% (41/42), 70.0% (7/10)， 93.2% (41/44)， 87.5%(7/8) and 92.3%(48/52) respectively. The diagnostic results of 18 F-FDG PET/CT are highly consistent with histopathological and (or) clinical follow-up results (Kappa value=0.732，P＜0.01). Conclusion 18 F-FDG PET /CT can reliably identify and accurately detect the recurrence and (or) metastasis of cervical squamous cancer in patients with elevated SCC-Ag after treatment, which has important clinical application value.

Key words:  fluorodeoxyglucose F18, positron-emission tomography, tomography, X-ray computed, uterine cervical neoplasms, carcinoma, squamous cell, recurrence, neoplasm metastasis, squamous cell carcinoma antigen