Fluorine F 18 Sodium Fluoride Positron Emission Tomography in Evaluating Response to Dasatinib in Patients With Prostate Cancer and Bone Metastases

Inclusion Criteria: * Must be able to provide a written informed consent * Men 18 years or older with metastatic castration-resistant prostate cancer enrolling onto the Febbo clinical trial with dasatinib therapy (must meet all inclusion criteria for dasatinib treatment study and comply with requirements of that specific clinical trial) * Histologic confirmation of original prostate cancer diagnosis * Presence of at least one convincing bone metastasis as defined by bone scintigraphy, computed tomography (CT) scan (magnetic resonance imaging \[MRI\] if indicated), or plain X-ray * Must currently have castrate testosterone levels (\< 50 ng/dL) from orchiectomy or maintenance on a luteinizing hormone-releasing hormone (LHRH) agonist or LHRH antagonist Exclusion Criteria: * On the nilutamide-only arm (Arm A of the clinical therapeutic trial) * Note: However, if a patient crosses-over from nilutamide at the time of progression to add dasatinib therapy, he may be eligible for 18F-fluoride PET imaging protocol if he meets all inclusion criteria for this trial * Any condition that would alter the patient's mental status, prohibiting the basic understanding and/or authorization of informed consent * A serious underlying medical condition that would otherwise impair the patient's ability to receive treatment and imaging studies * Expected lifespan of 12 weeks or less * Extremely poor intravenous access, prohibiting the placement of a peripheral IV line for injection of radiotracer * Initiation of bisphosphonate therapy less than 4 weeks from the first PET scan * Radiation treatment to bone less than 4 weeks from first PET scan * Radiopharmaceutical treatment to bone less than 4 weeks from first PET scan * Treatment with granulocyte-macrophage colony stimulating factor (GM-CSF) or granulocyte CSF (G-CSF) within 4 weeks prior to first PET scan * Inability to lie still for the imaging * Weight \> 300 lbs. (due to equipment specifications)