In Vivo PARP-1 Expression With 18F-FluorThanatrace PET/CT in Patients With Pheochromocytoma and Paraganglioma

Overview

This study will enroll up to 30 evaluable patients with pheochromocytoma or paraganglioma who are undergoing surgical or systemic treatment. A pre-treatment 18F-FluorThanatrace (\[18F\]FTT) positron emission tomography/computed tomography (PET/CT) scan will be done prior to surgery or systemic therapy. PET/CT imaging will be used to evaluate PARP-1 expression in sites of pheochromocytoma or paraganglioma using the investigational radiotracer \[18F\]FTT. This is an observational study in that \[18F\]FTT PET/CT will not be used to direct treatment decisions. While patients and referring physicians will not be blinded to the \[18F\]FTT PET/CT results, treatment decisions will be made by the treating physicians based upon clinical criteria.

Up to 30 patients who will undergo approximately 60 minutes of dynamic scanning head to thigh starting at approximately the same time as the injection, this will be followed by a second head to thigh scan \[starting at approximately 90 minutes post injection. PET/CT imaging sessions will include an injection of ≤ 12 mCi of \[18F\]FTT intravenously (approximate range for most studies is anticipated to be 8-12 mCi). If surgery is performed according to standard of care tissue will be processed for both clinical and research use, if the subject has consented for use of tissue. Data will be collected to evaluate uptake of \[18F\]FTT in pheochromocytoma and paraganglioma and compare with PARP-1 activity and other experimental assays in tissue from biopsy and surgery, when available. All evaluable patients may undergo surgery or systemic therapy following the \[18F\]FTT PET/CT scan. Up to 10 patients undergoing systemic therapy may undergo a second (optional) scan that will be performed approximately 1-21 days after therapy has started. The second scan is obtained to evaluate whether the initiation of systemic therapy alters \[18F\]FTT uptake. As this is a pilot study, only a limited number of patients are sought for the second scan.