In recent years, the application of 18F-FDG PET (positron emission tomography) and MRI for breast lesion diagnosis was emerging. Imbriaco et al compared the diagnostic performance of 18F-FDG PET and MRI for suspicious breast lesions, with PET showing a sensitivity of 80% and specificity 100%; and MRI revealed a sensitivity of 95% and specificity of 98%. Lim et al studied 18F-FDG PET-CT with MRI to monitor treatment response for breast cancer patients receiving NAC, with a sensitivity 70% and specificity 72%, and can detect the treatment response earlier than conventional imaging.
However, 18F-FDG is not tumor specific, and searching for an alternative tracer agent as a tumor biomarker is necessary. 18F-Fluorocholine (FCH), a choline analog, was used for diagnosis of prostate cancer, hepatocellular carcinoma (HCC), bronchioloalveolar carcinoma, brain tumor, since malignant tumors show higher choline metabolites than benign lesions; it was reported that FCH PET showed higher sensitivity (88-94%) than 18F-FDG PET (59-68%) in detecting HCC. FCH PET was used for staging for prostate cancer, with FCH PET-CT can provide sufficient information for management with an accuracy of 88%.