F 18 FDG PET/CT in Evaluation of Loco-regional and Distant Recurrent Cervical Carcinoma.

Document Type : Original Paper, PET/CT

Authors

1 Nuclear Medicine Unit, Egypt.

2 Radiology Department, National Cancer Institute, Cairo University, Cairo, Egypt.

Abstract

Aim: To evaluate the diagnostic performance of F-18 FDG PET/CT for the detection of local and distant disease relapse in treated patients with cervical carcinoma. Materials and Methods: This retrospective study includes 43 patients with pathologically proven cervical carcinoma, 36 patients were pathologically proven as Squamous Cell Carcinoma (SQ.C.C.) and 7 were adenocarcinoma. They received initial treatment and with clinico-laboratory suspected recurrence. They referred to nuclear medicine unit, to perform F-18 FDG PET/CT study. Sites of the relapse (classified as positive or negative) were categorized into local and distant recurrence. The final diagnosis of disease status was made on subsequent follow up by conventional imaging (CT/MRI), F-18 FDG PET/CT, or histopathology whenever possible.
Results: 34 (79.1%) of the patients were proven to have loco-regional &/or distant recurrence based on histopathology & or follow up. F-18 FDG PET/CT changed management in 8 patients (18.6% of the group). On per patient based analysis for detection of loco-regional and distant recurrence, F-18 FDG PET/CT, outperformed Ce-CT alone as regards the sensitivity indices with NPV 88.89% for F-18 FDG PET/CT compared to 66.67% for Ce-CT alone.
As regards loco-regional recurrence, and on per lesion based analysis, statistically higher sensitivity and NPV were seen with F-18 FDG PET/CT of 100% exceeding those of Ce-CT alone(SN 71.11% & NPV 80.6%) with P-value 0.0001 & 0.002 respectively, with overall diagnostic accuracy reached 98.06% with F-18 FDG PET/CT compared to 83.5% with Ce-CT (P-value 0.017). Distant metastases were also analyzed on per lesional basis where PET/CT revealed higher sensitivity and specificity indices compared to Ce-CT, with sensitivity, specificity, NPV and overall accuracy were 97.92%, 83.33%, 89.29%, & 95.4% respectively compared to 82.64%, 66.67%, 44.44%, 79.89%, for Ce-CT respectively with P-value <0.05.Conclusion: F-18 FDG PET/CT appears to be an efficient tool in detection of loco-regional and distant recurrence in cervical carcinoma patients.

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