This prospective phase II diagnostic feasibility study investigates the diagnostic potential of 68-Gallium PSMA-PET/CT in stereotactic irradiated brain metastases from non-small cell lung cancer, melanoma and breast cancer.
Participants will be enrolled in three predefined cohorts per primary tumor type:
1. newly diagnosed brain metastases,
2. definite radiation necrosis, and
3. diagnostic dilemma after radiotherapy.
The goals of this study are:
1\. Evaluating PSMA expression using Ga68-PSMA PET/CT in brain metastases of NSCLC, breast cancer and melanoma patients eligible for stereotactic radiotherapy (SRT) or surgery. 2. Evaluating PSMA expression using Ga68-PSMA PET/CT in patients with definite radiation necrosis. 3. Evaluating the use of Ga68-PSMA PET/CT to differentiate progressive brain metastases of NSCLC, breast cancer and/ or melanoma from radiation necrosis by quantifying PSMA activity.
