Imaging uterine cervical cancer with FDG-PET/CT: direct comparison with PET.

PURPOSE: To compare 2-deoxy-2-[F-18]fluoro-D-glucose-positron emission tomography (FDG-PET) and PET/computed tomography (CT) for certainty of image interpretation and for diagnostic accuracy in patients with primary and metastatic uterine cervical cancer.

MATERIALS AND METHODS: Images of 13 patients with cervical cancer having PET/CT examinations were reviewed retrospectively. PET and PET/CT images of all cases were read blindly and randomly by two readers. Foci of increased FDG uptake on PET or PET/CT were classified using a scoring system regarding lesion localization and characterization. PET and PET/CT findings were assessed with all clinical information available, and diagnostic accuracy was determined on a per-lesion and on a per-patient basis.

RESULTS: For both readers, PET/CT provided significantly higher frequencies of definite lesion localization (>30% higher) and definite lesion characterization (>20% higher) compared to the findings on PET alone. The improvement in lesion localization to the definite level by PET/CT provided the definite lesion characterization in at least 50% of cases. PET/CT tended to exhibit higher diagnostic accuracy than PET alone on a lesion-based analysis (92% vs. 78% in reader 1 and 92% vs. 82% in reader 2, respectively). Metastatic disease spread was, however, almost equally evaluated between PET and PET/CT.

CONCLUSION: PET/CT was demonstrated to be useful in the definite localization and characterization of foci of increased FDG uptake, which provided its higher diagnostic accuracy than PET alone. PET/CT appears preferable to PET in the evaluation of cervical cancer, although additional study is needed.