Role of 18F-FDG PET/CT in the detection of ovarian cancer recurrence in the setting of normal tumor markers

Purpose: To evaluate the diagnostic performance of 18F-flurodeoxyglucose positron emission tomography/contrast enhanced computed tomography (18F-FDG PET/CT) in patients with clinically/radiologically suspected ovarian tumor recurrence and normal tumor markers. Materials and methods: A total of 54 18F-FDG PET/CT studies from 41 patients with suspected ovarian tumor recurrence and normal tumor markers were evaluated. Each patient underwent PET/CT with CE-CT scans in the same study. 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 recurrence (local, regional or distant). The final diagnosis of tumor status was made on the basis of subsequent follow-up by conventional imaging (CT/MRI), 18F-18F-FDG PET/CT or histopathology whenever possible. Results: Of the 54 studies evaluated, 26 (48%) studies had tumor recurrence and 28 (52%) studies were disease-free based on final diagnosis. Combined 18F-FDG PET/CT vs. CE-CT alone showed sensitivity, specificity and accuracy of 92% vs. 73%, 90% vs. 55%, and 91% vs. 63%, respectively. 18F-18F-FDG PET/CT was significantly more sensitive, more specific and more accurate compared to CE-CT with P-values of 0.06, 0.006 and 0.0001, respectively. Site-based analyses were also performed and showed significantly higher diagnostic indices for combined FDG-PET/CT. Conclusion: Combined 18F-FDG PET/CT with contrast enhancement is more accurate than CE-CT alone in the diagnosis of ovarian tumor recurrence in patients with normal tumor markers

Utility of left lateral supine position for myocardial perfusion single-photon emission computed tomography compared with other methods of correcting inferior wall attenuation

Introduction Single-photon emission computed tomography (SPECT) myocardial perfusion imaging is an accepted method for reflecting the pathophysiological significance of lesions detected by coronary angiography. However, it has an inherent drawback in terms of false-positive perfusion defects for the inferior myocardial wall. To overcome this problem, different acquisition techniques have been proposed, including the computed tomographic-based attenuation correction method. In this respect, a new imaging technique, left supine lateral position SPECT myocardial perfusion imaging with technetium-99m methoxyisobutylisonitrile (Tc-99m MIBI), has been proposed to eliminate this problem and its value has been investigated in this report