Using Molecular Imaging to Enhance Decision Making in the Management of Pituitary Adenomas

Inmost patients with suspected or confirmed pituitary adenomas (PAs), MRI, performed using T1- (with or without gadolinium enhancement) and T2-weighted sequences, provides sufficient information to guide effective clinical decision making. In other patients, additional MR sequences (e.g., gradient recalled echo, fluid-attenuation inversion recovery, MR elastography, or MR angiography) may be deployed to improveadenoma detection, assess tumoral consistency, or aid distinction from other sellar/parasellar lesions (e.g., aneurysm, meningioma). However, there remains a small but important subgroup of patients in whom primary or secondary intervention (e.g., first or redo transsphenoidal surgery, stereotactic radiosurgery) is limited by the inability of MRI to accurately localize the site(s) of de novo, persistent, or recurrent PA. Emerging evidence indicates that hybrid imaging, which combines molecular (e.g. C-11-methionine PET) and cross-sectional (MRI) modalities, can enable the detection and precise localization of sites of active tumor to guide targeted intervention. This not only increases the likelihood of achieving complete remission with preservation of remaining normal pituitary function but may mitigate the need for long-term (even lifelong) high-cost medical therapies. Here, we review published evidence supporting the use of molecular imaging in the management of PAs, including our own 10-y experience with C-11-methionine PET.

Automated summary

For most patients with suspected or confirmed pituitary adenomas, MRI is usually sufficient for clinical decision making, but additional MR sequences may be needed for certain patients. There is a subgroup of patients for whom MRI cannot accurately localize the tumor site, leading to limited intervention options. Emerging evidence suggests that hybrid imaging, combining molecular and cross-sectional modalities, can improve tumor detection and localization for targeted intervention, potentially reducing the need for long-term high-cost therapies.