Prostate Active Surveillance Study

Inclusion Criteria:

* Histologically confirmed adenocarcinoma of the prostate from a prostate biopsy.
* Clinically localized prostate cancer: T1-2, NX or N0, MX or M0.
* No previous treatment for prostate cancer (including hormonal therapy, radiation therapy, surgery, or chemotherapy).
* ECOG Performance Status 0 or 1.
* Patient has elected Active Surveillance as preferred management plan for prostate cancer.
* Patient consent has been obtained according to local Institutional Review Board for acquisition of research specimens.
* Patient is accessible and compliant for follow-up.
* Prostate cancer diagnosis cannot be more than 3 years prior to baseline visit date.
* No more than two prostate biopsies including the initial biopsy in which cancer was diagnosed.
* If cancer diagnosis is more than one year before enrollment, there must be two prostate biopsies including the initial biopsy in which cancer was diagnosed and a subsequent biopsy. The subsequent biopsy may occur on the same day as the baseline visit.
* Biopsies must have at least 10 cores.

Exclusion Criteria:

* Unwillingness or inability to undergo serial prostate biopsy.
* History of other malignancies, except: adequately treated non-melanoma skin cancer or adequately treated superficial bladder cancer (Ta) or other solid tumors curatively treated with no evidence of disease for \> 5 years.