Stereotactic body radiotherapy: an emerging treatment approach for localized prostate cancer.

Here we report results from the first cohort of over 100 patients treated with hypofractionated, stereotactic body radiotherapy (SBRT) for early stage prostate cancer. Between February 2005 and December 2006, 112 patients with localized, biopsy-proven adenocarcinoma of the prostate (clinical stage T1cN0M0 to T2cN0M0) were treated in Naples, FL on a CyberKnife system (Accuray Incorporated, Sunnyvale, CA). Eighty-one patients had a Gleason score of 3+3. Mean initial PSA was 6.0, and mean initial prostate volume was 46.3cc. Implanted gold fiducials were used for image-guided targeting and tracking. Patients received 35-36 Gy administered in 5 consecutive fractions to the prostate and the proximal seminal vesicles, as identified on CT and MRI scans. At a median follow-up of 24 months, the mean PSA value was 0.78 ng/ml. Two patients have developed biopsy-confirmed local relapse; one developed distant metastases. Acute side effects were generally mild and resolved shortly after treatment. A single Grade 3 rectal complication was reported (bleeding). Eighty-two percent of patients who were sexually potent before treatment maintained erectile function post-treatment. Additional follow-up is required to better evaluate potential late toxicity and long-term PSA outcomes.

Treatment of intermediate-risk prostate cancer with brachytherapy without supplemental pelvic radiotherapy: a review of the H. Lee Moffitt Cancer Center experience.

PURPOSE: To determine the biochemical outcomes of patients with intermediate-risk prostate cancer treated at the H. Lee Moffitt Cancer Center with an I-125 permanent seed implant without supplemental pelvic radiotherapy. METHODS AND MATERIALS: Under an institutional review board approved protocol, the charts of 88 patients with intermediate-risk prostate cancer and a minimum follow-up of 36 months treated with brachytherapy without supplemental pelvic radiotherapy were reviewed. Median follow-up for the whole cohort was 57 months (range 37-121). Biochemical failure was defined using the American Society for Therapeutic Radiology and Oncology definition. RESULTS: The 5-year biochemical failure-free survival for the cohort was 83%. Patients with perineural invasion had a worse biochemical outcome, which was statistically significant (perineural invasion vs. no perineural invasion, 5-year biochemical failure-free survival 64% vs. 89%, P = 0.004). None of the following factors were found significant in this subset of patients: Gleason scores 6 versus 7, primary Gleason grades 3 versus 4, percentage of core positive <20% versus >20%, number of cores positive <2 versus 2 versus >2, hormonal therapy versus no hormonal therapy, T1 versus T2, prostate-specific antigen <10 versus >10, or > or =2 intermediate risk factors versus 1 intermediate risk factor. CONCLUSIONS: Our data suggest that patients with intermediate-risk prostate cancer may be treated effectively with brachytherapy without supplemental pelvic radiotherapy. However, because of the limited nature of our study, we cannot exclude that patients with intermediate-risk prostate cancer may benefit from supplemental external beam radiotherapy.

Managing toxicities in pelvic malignancies.

Pelvic malignancies, including bladder, prostate, and gynecologic cancers, are typically treated with some form of radiation therapy. Reducing radiation-related toxicities in these patients is important for maintaining good quality of life as survival rates increase and also for directly affecting cure rates by reducing delays in radiotherapy. Amifostine (Ethyol) has been shown to reduce rectal bleeding in patients with prostate cancer treated with radiation therapy, prevent radiation-related dermatitis, and provide widespread mucosal protection without adversely affecting local or distant tumor control.