Value of 18F-FDG PET/CT in diagnosing suspected recurrence and metastasis in gynecological malignancies

Objective: Recurrence and metastasis are significant prognostic factors in patients with gynecological malignancies. The purpose of the study was to evaluate the value of 18F-fluorodeoxyglucose (FDG) PET/CT in diagnosing suspected recurrence and metastasis in gynecological malignancies, and to investigate the influence of PET/CT on clinical restaging and treatment decision. Methods: Forty-seven patients with gynecological malignancies clinically suspected of recurrence or metastasis underwent 18 F-FDG PET/CT imaging. The images of 18F-FDG PET/CT, PET and CT were compared respectively. χ2-test with SPSS 12.0 was used for data analysis. Results: One hundred and forty-nine malignant lesions and 9 benign lesions were found in 47 patients. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of 18 F-FDG PET/CT in detecting recurrence and metastasis of gynecological malignancies were 95.97% ( 143/149), 6/9, 94.30% ( 149/158), 97.95% (143/146) and 50.00% ( 6/12), respectively. The difference was significant between ,18 F-FDG PET/CT image and CT alone in sensitivity, accuracy and negative predictive value (χ2 = 18.198, 18.890, 6.825, all P <0.05). Compared with 18F-FDG PET/CT image, PET alone had no difference in the qualitative diagnostic accuracy (χ2 = 0.632, 0.000, 0.459, 0.000, 0.150, all P>0.05), but 18F-FDG PET/CT had a clear advantage in determining the location of the lesions [33.54% (53/158)]. PET/CT changed the TN M staging in 44.68% ( 21/47 ) and 31.91% (15/47) patients, respectively, comparing with CT or PET alone. Furthermore, 19.15% ( 9/47 ) had change in their clinical staging and treatment decision based on the results of PET/CT. Conclusion: 18F-FDG PET/CT is valuable in the detection, restaging and management decision in recurrent and metastatic gynecological malignancies. (authors)