Diagnostic performance of 11 C-choline PET/CT and FDG PET/CT for staging and restaging of renal cell cancer.

Purpose: To compare findings obtained with ¹¹ C-choline and FDG PET/CT scanning for renal cell carcinoma staging and restaging.
Materials and Methods: Twenty-eight renal cell carcinoma patients whose histological subtype was clear cell type in 26 and papillary type in 2, while Fuhrman nuclear grade was G1,2 in 16 and G3,4 in 12, underwent both ¹¹ C-choline and FDG PET/CT examinations before (n = 10) and/or after (n = 18) treatment, then those scanning modalities were compared in regard to patient- and lesion-based diagnostic performance using 5 grading scores. Final diagnosis in each case was obtained based on histopathology, conventional radiological imaging, and clinical follow-up findings. The differences between ¹¹ C-choline and FDG PET/CT findings were evaluated using receiver-operating-characteristic (ROC) analysis and a McNemar test.
Results: Patient-based sensitivity, specificity, positive predictive, negative predictive, accuracy, and area under the ROC curve (AUC) values for ¹¹ C-choline PET/CT for staging and restaging were 88.0% (22/25), 66.7% (2/3), 95.7% (22/23), 40.0% (2/5), 85.7% (24/28), and 0.887, respectively, while those for FDG-PET/CT were 56.0% (14/25), 66.7% (2/3), 93.3% (14/15), 15.4% (2/13), 57.1% (16/28), and 0.647, respectively. Sensitivity, accuracy, and AUC were significantly different (p = 0.013, p = 0.013, p = 0.012, respectively). Among the 120 lesions, those with kidney, lung, lymph node, bone, pancreas, venous tumor thrombosis, adrenal gland, liver, or skin localization numbered 15, 64, 16, 13, 4, 3, 2, 2, and 1, respectively. For all 120 lesions, 75 (62.5%) and 47 (39.2%) were detected by ¹¹ C-choline and FDG PET/CT, respectively (p < 0.0001).
Conclusion: For staging and restaging of renal cell carcinoma patients, ¹¹ C-choline-PET/CT is significantly more useful than FDG-PET/CT.