Avodart (dutasteride) reduces the male hormone (DHT) that leads to prostate growth and stimulates cancerous growth. Avodart is currently approved by the FDA to treat men with symptoms of an enlarged prostate. Avodart works by reducing DHT and prostate size; therefore, the drug may be useful in improving lower urinary tract symptoms (LUTS) such as frequency, urgency, weak stream, and urination difficulty (dysuria), among others, in men with prostate cancer. Avodart may be effective in men with prostate cancer who are being treated with hormonal therapy with one injection of Zolodex (goserelin) followed one month later with a trans-urethral incision of the prostate (TUIP), and three months after that, seed implantation (SI) of the prostate.

The purpose of this study is to test whether Avodart (dutasteride) is effective on LUTS and dysuria in men with localized prostate cancer being treated with single-dose goserelin, TUIP, and interval SI.

Dutasteride is an inhibitor of the 5 alpha reductase type I and type II enzymes that convert testosterone to DHT, the male hormone that leads to benign prostate growth and drives malignant growth. Dutasteride has been shown to significantly decrease intraprostatic DHT in men with localized prostate cancer, and additionally cause apoptosis and regression of some prostate cancers [Andriole, 2004a; Andriole, 2004b]. Furthermore, reduction in tumor volume has also been demonstrated in human prostate tissue [Iczkowski, 2004]. Dutasteride is currently indicated to treat symptomatic BPH in men with enlarged prostates, but is also being studied to reduce the risk of prostate cancer in men at risk (elevated PSA and previous negative biopsy). Dutasteride is clinically useful at improving lower urinary tract symptoms (LUTS) in men with clinically-localized prostate cancer and voiding difficulty being treated with single-dose goserelin, TUIP, and interval SI. [Mitcheson, personal observation].

Inclusion Criteria:A subject will be eligible for inclusion in this study only if all of the following criteria apply:

1. Must be male ≥35 and ≤90 years of age
2. Have biopsy proven, localized prostate cancer
3. Gleason score ≤ 8
4. Clinical stage T1c-T2b
5. Serum PSA (prostate specific antigen) ≤10ng/mL within the 12 months period prior to positive prostate biopsy.
6. Able to swallow and retain oral medication
7. Able and willing to participate in the full duration of the study
8. Able to read and write (health outcomes questionnaires are self-administered), understand instructions related to study procedures and give written informed consent.

Exclusion Criteria:

1. Subject has ever been treated for prostate cancer with any of the following:

   • Radiotherapy (external beam or brachytherapy)
   • Chemotherapy
   • Hormonal therapy (e.g., megestrol, medroxyprogesterone, cyproterone, diethyl-stilbestrol (DES)
   • Oral glucocorticoids
   • Gonadotropin Releasing Hormone (GnRH) analogues (e.g., leuprolide, goserelin) other than the single-dose gosereline given as treatment in this study.

2. Glucocorticoids, except inhaled or topical, are not permitted within 3 months prior to visit one

3. Current and/or previous use of the following medications:

   • Finasteride (Proscar, Propecia), or Dutasteride (Avodart) exposure within 6 months prior to study entry are excluded.
   • Any other investigational 5-reductase inhibitors within the past 12 months.
   • Anabolic steroids (subject must discontinued for 6 months prior to study entry to be eligible)
   • Drugs with antiandrogenic properties within the past 6 months (e.g,. spironolactone, flutamide, bicalutamide, *cimetidine, *ketoconazole, progestational agents) *The use of cimetidine is permitted prior to study entry. The use of topical ketoconazole is permitted prior to and during the study.