Overview
This study aims to evaluate the diagnostic potential of 68-Gallium PSMA-PET/CT in stereotactic irradiated brain metastases from non-small cell lung cancer, melanoma and breast cancer.
Description
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:
- newly diagnosed brain metastases,
- definite radiation necrosis, and
- 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.
Eligibility
Inclusion Criteria:
For all groups:
- Written informed consent
- Age ≥ 18 years old
- WHO PS 0-3
- Measurable lesion ≥10mm according to RANO BM
For brain metastases groups:
\- newly diagnosed brain metastases from either NSCLC (group 1) or melanoma (group 2) or breast cancer (group 7).
For radiation necrosis groups:
\- Brain lesion at the location of a formerly brain metastases that has been treated with SRT (\> 9 months ago), with the definite diagnosis of radiation necrosis at the location of formerly SRT-treated brain metastases of NSCLC (group 3), melanoma (group 4) and/ or breast cancer (group 8).
For diagnostic dilemma groups:
\- Brain lesion at the location of a formerly brain metastases with a diagnostic dilemma of radiation necrosis and recurrent brain metastases of NSCLC (group 5), melanoma (group 6) and/ or breast cancer (group 9).
Exclusion Criteria:
For all groups:
- Known allergy to Ga68-PSMA
- Epileptic seizure less than 7 days before Ga68-PSMA PET/CT scan
- Life expectancy less than 3 months
- Patients with known prostate carcinoma
- Pregnancy


