Metabolic Change in Prostate Cancer Bone Metastases on 68Ga-HBED-CC-PSMA PET/CT Following Radium-223 Therapy

Metabolic Change in Prostate Cancer Bone Metastases on 68Ga-HBED-CC-PSMA PET/CT Following Radium-223 Therapy

Broadly, the objective of this study is to evaluate the fractional decline of intensity of tracer uptake measured by SUVmax on 68Ga-PSMA PET/CT in bone metastases from prostate cancer following treatment with radium-223 as a surrogate marker for tumor cell killing.

Inclusion Criteria

• Resident of Canada
• Male sex
• Age 18 years or older
• Progressive (symptoms, conventional imaging, PSA, bone scan, FCH PET/CT or other) castration-resistant prostate cancer in the judgment of the treating physician without change in systemic anti-neoplastic therapy since documented progression
• Six or greater bone metastases robustly-avid on recent (4 weeks) MDP or NaF scintigraphy
• Recently failed (within 3 months) or failing novel androgen receptor pathway inhibitors (abiraterone + prednisone or enzalutamide) with intention of continuing the drug for at least 7 months OR minimum 14 day washout period from either agent prior to study enrollment
• No known visceral metastases or adenopathy greater than 3 cm short axis on conventional imaging
• Not received docetaxel for castration-resistant disease
• ECOG performance status 0 - 2, inclusive
• Life expectancy of greater than 6 months
• Serum testosterone less than or equal to 50 ng/dl
• Hemoglobin greater than or equal to 100 g/L with no blood transfusions or EPO in preceding 3 weeks
• Neutrophils greater than or equal to 1.5 x109/L
• Platelets greater than or equal to 100 x109/L
• No prior hemi-body radiotherapy
• No impending or established spinal cord compression
• No unmanageable fecal incontinence
• Patient has good IV access
• Able to understand and provide written informed consent

Exclusion Criteria

• Planned change in systemic anti-neoplastic therapy during the approximately 7 month trial
• Unable to tolerate the physical/logistical requirements of a PET/CT scan including lying supine for up to 30 minutes with the arms above the head and tolerating intravenous cannulation for injection of the study drug.
• Medically unstable patients (e.g. acute cardiac or respiratory distress or hypotensive, etc.)
• Patients who exceed the safe weight limit of the PET/CT bed (approximately 400 lbs.) or who cannot fit through the PET/CT bore (70 cm diameter)
• Patients who are claustrophobic