18F-FDG PET/CT Outperforms Contrast Enhanced CT in the Diagnosis of Peritoneal Metastases from Ovarian Tumors

Objectives: To evaluate the diagnostic
performance of 18F-Flurodeoxyglucose
positron emission tomography/
computed tomography in comparison
to contrast enhanced computed
tomography alone in the detection of
peritoneal metastases after initial
treatment of malignant ovarian tumors.
Patients and Methods: The study
prospectively recruited 111 patients
with clinical suspicion of ovarian tumor
recurrence. Each patient underwent 18FFDG
PET/CT and Ce-CT scans in the
same day. Study-based analyses for a
total of 136 scans were evaluated.
Studies were read independently by one
experienced nuclear medicine
physician and one experienced
radiologist. A four-point score (score
0= definitely benign, score 1 = probably
benign, score 2= probably malignant
and score 3= definitely malignant) used
to assess the presence or absence of
peritoneal metastases. The final
diagnosis of peritoneal disease status
was made on the basis of subsequent
follow-up by 18F-FDG PET/CT,
conventional imaging (CT/MRI) or
histopathology whenever possible.
Results: Of the 136 studies evaluated,
75 (55%) studies had peritoneal disease
and 61 (45%) studies were free based
on final diagnosis.18F-FDG PET/CT &
Ce-CT had sensitivity, specificity and
accuracy of 96% vs 69%, 100% vs
85%, and 98% vs 76%; respectively.
18F-FDG PET/CT was significantly
more sensitive, specific and accurate
compared to Ce-CT with P-values
of <0.0001, 0.004 and <0.0001;
respectively. Conclusions: 18F-FDG
PET/CT is superior to Ce-CT in the
diagnosis of peritoneal metastases in
patients with malignant ovarian tumors.