Chemotherapy Response Monitoring With 18F-choline PET/CT in Hormone Refractory Prostate Cancer

Patients who meet eligibility criteria and are enrolled will undergo whole-body imaging with 18F-choline PET/CT at 3 time points during the course of treatment that is indicated for castrate resistant prostate cancer. The 1st PET/CT scan is performed at baseline before treatment initiation. The 2nd and 3rd scans are performed at two other treatment-releated timepoints or at approximately 1 month and 3 months after treatment initiation. Change in lesion 18F-choline uptake from baseline measured at each time point will be determined. Cancer 18F-choline uptake will be evaluated as a marker of therapeutic response in comparison to PSA response and symptom scores. Treatment-related changes in tumor 18F-choline uptake occur will be studied after the second and third PET scans to determine the acuity by which changes in tumor 18F-choline uptake can be expected following specific treatments for castrate-resistant prostate cancer. The study evaluates a diagnostic intervention and the treatments themselves are not considered part of the investigation. All treatment decisions will be made independent of the study and must be deemed clinically-warranted by a treating physician.

Inclusion criteria

• Provision of written informed consent.
• Men, over 18 years of age, with histologically-confirmed diagnosis of prostate cancer
• History of treatment by complete androgen blockade for greater than 3 months prior to enrollment
• Progressive disease evidenced by 2 consecutive rises in PSA measured at least 1 week apart, with the absolute value of the latest PSA > 5.0 ng/ml.
• A rise in PSA following anti-androgen drug withdrawal, above the last PSA value before withdrawal.
• Patient has agreed to treatment for hormone-refractory (ie. castrate-resistant) prostate cancer under supervision of a medical oncologist, urologist, radiation oncologist or nuclear medicine physician. Treatments indicated for HRPC are docetaxel-, cabazitaxel-, or mitoxantrone-based chemotherapy, abiraterone, radium-223, enzalutamide, or sipulecuil-T.

Exclusion criteria

• Other co-existing malignancies or malignancies diagnosed within the last 5 years with the exception of basal cell carcinoma or superficial transitional cell carcinoma of the bladder.
• Serious underlying medical conditions that would otherwise impair the patient's ability to undergo imaging.
• Patient weighs over 350 lbs (due to scanner weight limit).
• Clinical life expectancy < 12 weeks.
• Participated in other radioactive drug studies where estimated total cumulative dose within 1 year is > 0.05 Sievert for whole body, active blood-forming organs, eye lens, gonads, or 0.15 Sievert for other organs.
• Concurrent Therapy. Allowed: Prior or concurrent chemotherapy, but must be > 12 weeks since last treatment at enrollment; prior or concurrent hormonal therapy; prior surgery; prior or concurrent bisphosphonate; prior or concurrent receptor/biologic agent allowed if given on approved study protocol.