Using Desmopressin-Stimulated FDG PET Imaging to Detect MRI-Negative Pituitary Adenomas in Cushings Disease Assessing Tumor Location Accuracy Compared to Surgery and Histology

What this Trial Is About

Researchers are evaluating the use of DDAVP-stimulated 18F-fluorodeoxyglucose FDG PET imaging to detect MRI-negative pituitary adenomas in patients with Cushings disease. This single institution trial focuses on subjects with small pituitary tumors who have biochemical evidence of Cushings disease but show negative or unclear results on standard MRI scans. The goal is to improve detection and localization of these tumors to aid surgical planning and treatment. Participants aged 8 years and older who are surgical candidates for resection of ACTH-producing pituitary adenomas will receive intravenous DDAVP Desmopressin acetate 10 mcg, followed approximately four hours later by FDG administration for high-resolution PET imaging. Within 24 weeks after PET imaging, subjects will undergo surgical removal of the tumor. PET images will be independently reviewed by neuroradiologists who are unaware of surgical or histological findings to assess the accuracy of DDAVP-stimulated PET imaging compared to MRI and surgical results. During the study, participants will have MRI scans within 9 months prior to screening, PET imaging with DDAVP stimulation, and surgical evaluation of the pituitary adenoma. Researchers will compare PET imaging results with surgical and histological confirmation of tumor location to determine diagnostic accuracy. Safety and liver function will be monitored, and eligibility includes tolerance to previous DDAVP administration. The primary outcome is detection of tumors by PET imaging in MRI-negative cases, with secondary outcomes assessing localization accuracy compared to surgery and histology.

DDAVP for Pituitary Adenoma