The effectiveness of whole body magnetic resonance imaging (diffusion-weighted imaging and fat saturated T2-weighted imaging) in the evaluation of patients with newly diagnosed malignancies in comparison with positron emission tomography-computed tomography.

PURPOSE: To evaluate the effectiveness of WB-MRI for the detection of primary and metastatic lesions in comparison to PET-CT in patients with newly diagnosed malignancies MATERIAL AND METHODS: In this prospective study, 36 patients were evaluated between August 2008 and October 2012. The findings of WB-MRI (DWI and fat saturated T2 weighted images) were compared to the findings of PET-CT re- garding the primary lesions and metastasis. Sensitivity, specificity, positive and negative predictive values were calculated. To assess the aggreement between PET-CT and WB-MRI, kappa analysis was performed. RESULTS: The sensitivity, specificity, positive and negative predictive values for WB-DWI for the detection of primary and metastatic lesions in comparison to PET-CT were 96%, 89%, 97% and 84%, respectively. These are calculated as 96%, 56%, 90% and 77%, for fat-saturated T2W images. According to kappa analysis, the agreement between PET-CT and WB-DWI was excellent (χ = 0.83), but between PET-CT and fat-saturated T2 weighted images, it was moderate (χ = 0.58). CONCLUSION: Providing both morphogical and functional data, WB-MRI with DWI is emerging as a promising alternative imaging tool in the evaluation of cancer patients and may become complementary to PET-CT in several clinical applications.

Demonstrating disease activity in patients with rheumatoid arthritis. Is 18F FDG PET a sensitive method?

AIM: We aimed to investigate the relationship of fluor-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F FDG PET/CT) with clinical, laboratory parameters and conventional radiographs in patients with rheumatoid arthritis (RA). PATIENTS, MATERIAL, METHODS: 25 patients with RA diagnosis were evaluated by sociodemographic, clinical [duration of disease (year), the joints in which the complaints started, most recent joint involvement]; other parameters used in RA-specific clinical assessment [Steinbocker functional staging, disease activity score 28 (DAS 28 score), health assessment questionnaire score (HAQ score), general RA assessment (patients' and physicians' global assessment), patients' assessments of pain and general health condition (visual analog scale)], laboratory, radiological [conventional radiology of hand and foot joints], positron emission tomography [18F FDG PET visual total score and maximum standardized uptake value (SUVmax) total score] parameters. RESULTS: No significant correlation was detected between the 18F FDG PET total score and SUVmax total score of the patients and clinical, laboratory, and radiological parameters (p > 0.05). There was no relationship between the cut-off values determined according to the disease activity and 18F FDG PET/SUVmax total values (p > 0.05). CONCLUSIONS: In our study, no relationship was found between disease activity demonstrated by 18F FDG PET/CT in RA patients and clinical, laboratory, and radiological parameters. 18F FDG PET/CT appears to be a more sensitive method in demonstrating disease activity compared to other evaluated methods.

Comparison of F18-FDG PET/CT findings with current clinical disease status in patients with Takayasu's arteritis.

OBJECTIVES: 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (F-18 FDG PET/CT) scanning has been proposed as a new tool to assess disease activity in Takayasu Arteritis (TA). We investigated whether F-18 FDG PET/CT findings were consistent with current clinical disease status in patients with TA. METHODS: In this cross-sectional study, 22 patients with TA were enrolled. Clinical disease activity was assessed by the combination of National Institutes of Health (NIH) criteria, Disease Extent Index-Takayasu (DEI-Tak) score, physician global assessment and F-18 FDG PET/CT scans. RESULTS: At the time F-18 FDG PET/CT scans were taken, the majority of the patients (17/22) were using immunosuppressive (IS) drugs, and only four patients had clinically active disease. F-18 FDG PET/CT scans confirmed the presence of active vasculitic lesions in those four patients. In 16 out of 18 patients who were accepted to be in clinical remission, F-18 FDG PET/CT scans were also normal. There were only two patients with discordant results, i.e. active F-18 FDG PET/CT findings despite the lack of clinical activity. Interestingly, clinical exacerbation occurred four weeks later in one of them. Overall sensitivity and specificity of F-18 FDG PET/CT findings for clinical activity were 100% and 88.9%, respectively. CONCLUSIONS: We found that F-18 FDG PET/CT findings were generally consistent with clinical disease status in TA. Although use of IS drugs certainly impairs diagnostic accuracy of F-18 FDG PET/CT in TA, this imaging method may still have a potential for confirming remission or detecting disease activity in patients with TA receiving treatment.