Pituitary Neuroendocrine Tumor Diagnosis
MRI is commonly used in the evaluation of pituitary neuroendocrine tumors (PAs). However, it has difficulty to locate the lesions sometimes, especially microadenomas and/or postoperative recurrent tumors. On the MRI they can present various enhancement patterns and other imaging features. About 18% of macroadenomas contain cystic components, and about 20% show foci of hemorrhage, which are usually clinically asymptomatic and diagnosed incidentally in MR imaging.
Positron emission tomography/CT may be useful to detect tumors in patients with equivocal MRI results.
11C methionine positron emission tomography PET/CT can provide valuable diagnostic information when F-FDG PET/CT yields negative results, especially in patients with recurrent microadenomas 1).