Stereotactic Body Radiation Therapy (SBRT) for Prostate Cancer

Phase I/II Trial of Stereotactic Hypofractionated Radiotherapy of the Prostate

The purpose of this study is to evaluate a short course (five radiation treatments) of very focused ("stereotactic") external beam radiation therapy for the treatment of early stage prostate cancer.

External beam radiation therapy for prostate cancer, while effective, takes up to 9 weeks to deliver on a Monday through Friday basis. Recent phase I/II studies from Seattle and Palo Alto using stereotactic guidance to deliver high doses of radiation to the prostate over a 1 to 2 week period of time suggest that outcomes may be equal or superior to standard approaches. These data, combined with markedly improved convenience for patients, make radiosurgery (SBRT) for early-stage prostate cancer an enticing option. The goal of this study is to offer a radiosurgical option to patients within the Sharp system under the umbrella of an IRB-approved study.

Inclusion Criteria:

• Male with any age (typically 50 to 70 years old) with a low risk disease. This is defined as a Gleason's score of 6 or less, clinical stage of T2a or less, and a PSA of less than 15. We will also include patients with Gleason's score of 3+4=7 if there are fewer than 2 cores positive, with no more than 5mm of tumor in aggregate dimension.

Exclusion Criteria:

• Prior surgery or radiotherapy for prostate cancer, PSA over 10, Gleason scores 7, 8, 9, or 10 (except Gleason 7 as noted, above), or clinical stage T2b, T2c, T3, or T4.