C-Acetate PET/CT Imaging to Evaluate Treatment Changes in Prostate Cancer

Inclusion Criteria: * Inclusion Criteria at least 18 years of age * History of biopsy proven or clinically documented castrate resistant prostate cancer which is metastatic to bone as assessed by medical record review. * Patients selected for Ra-223 dichloride therapy for treatment of bone metastasis by their treating physician. * Participants must be informed of the investigational nature of this study and provide written informed consent in accordance with institutional and federal guidelines prior to study-specific procedures. Exclusion Criteria: * Not on current androgen deprivation therapy or plan for withdrawal of androgen deprivation therapy * Cytotoxic chemotherapy within 4 weeks prior to study enrollment * Systemic radioisotope therapy within 24 weeks prior to study enrollment * Eminent or established cord compression as assessed by medical record review * History of hemibody external radiotherapy as assessed by medical record review * Inability to tolerate imaging procedures in the opinion of an investigator or treating physician * Serious or unstable medical or psychological comorbidities that, in the opinion of the investigator, would compromise the subject's safety or successful participation in the study. * Documented visceral metastases or current lymphadenopathy \> 3 cm by standard imaging (e.g. MRI, CT, ultrasound, FDG PET/CT) * Only individuals (aged 18 or over) who can understand and give informed consent will be eligible to participate in this study. Individuals who are considered to be mentally disabled will not be recruited for this study. All subjects must be able to give informed consent. We will not be using specific methods to assess decisional capacity. Economically disadvantaged persons will not be vulnerable to undue influence, as this study offers no compensation. All individuals will be told that their choice regarding study participation will in no way change their access to clinical care. This should negate any undue influence or coercion. Women, children, fetuses, neonates, or prisoners are not included in this research study.