The purpose of this study is to determine if the planning of radiation treatment of prostate cancer patient can be made more precise by comparing currently planning techniques to an imaging technique called SPECT.

Single photon emission computed tomography (SPECT) uses radioactive tracers and a scanner to record data that a computer constructs into two- or three-dimensional images. A small amount of a radioactive drug is injected into the body and a scanner is used to make detailed images of areas inside the body where the radioactive material is taken up by the cells. Using a gamma camera (a special kind of scanner), we can create a better picture of the lymph node region. We will compare these pictures to images from your CT scan, to help plan your therapy.

The research in this study involves seeing if it is feasible to use SPECT scanning procedures for the purpose of planning your radiation treatment. We hope that doing so will allow us to more accurately and precisely plan radiation treatment to potential sites of cancer, and avoid delivering too much radiation to normal

Inclusion Criteria:

• Patients with biopsy proven adenocarcinoma of the prostate
• Patients with at least one of the following high risk clinical features at the time of presentation:
• Extra-prostatic extension (on palpation or radiographic imaging)
• PSA ≥ 20
• Gleason Score ≥ 8
• Patients scheduled to receive prostatic and pelvic IMRT with ACCULOC® target localization
• Age > 18 years
• ECOG Performance Status ≤ 2
• Willing and able to sign informed consent document.-

Exclusion Criteria:

• History of radical prostatectomy
• History of prior pelvic radiation-