Inclusion Criteria:

1. Provision of written informed consent.

2. Men, over 18 years of age, with histologically-confirmed diagnosis of prostate cancer

3. History of treatment by complete androgen blockade for greater than 3 months prior to
enrollment

4. Serum testosterone level < 50 ng/ml. Castrate testosterone levels must be from
orchiectomy or current therapy with leutinizing hormone-releasing hormone agonist.

5. Progressive disease evidenced by two consecutive rises in PSA above a nadir value,
with the absolute value of the latest PSA > 2. 0 ng/ml.

6. Patient will be undergoing a therapeutic intervention under the supervision of his
treating physician (urologist, oncologist).

Exclusion Criteria:

1. 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.

2. Serious underlying medical conditions that would otherwise impair the patient's
ability to undergo imaging.

3. Patient weighs over 350 lbs (due to scanner weight limit).

4. Clinical life expectancy < 12 weeks.

5. 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.

6. Concurrent Therapy. Allowed: prior hormonal therapy; concurrent LHRH agonist; prior
surgery; prior or concurrent bisphosphonate. Not allowed: concurrent anti-androgen or
secondary hormonal therapy, prior or concurrent chemotherapy, concurrent radiotherapy
or radioisotope therapy (e.g., strontium). Other: Prior radiotherapy or radioisotope
therapy must be > 12 weeks since last treatment.