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Updated: Jan 24, 2026
08:54
Treatment of Liver Metastases Using an Internal Target Volume Method for Stereotactic Body Radiotherapy
Published on: May 8, 2018
14.9K
Phase 2 Multicenter Trial of Heterogeneous-dosing Stereotactic Body Radiotherapy for Low- and Intermediate-risk
Donald B Fuller1, Aaron D Falchook2, Tami Crabtree3
1CyberKnife Centers of San Diego, San Diego, CA, USA.
European Urology Oncology
|June 4, 2019
Summary
Stereotactic body radiation therapy (SBRT) for prostate cancer (PC) shows excellent 5-year efficacy with high biochemical recurrence-free survival rates. This novel 4-day SBRT regimen is effective and well-tolerated for low- and intermediate-risk PC.
Area of Science:
- Oncology
- Radiation Oncology
- Urology
Background:
- Stereotactic body radiation therapy (SBRT) is an emerging treatment for prostate cancer (PC).
- A 38Gy in 4 fractions schedule has shown efficacy in high-dose-rate (HDR) brachytherapy.
Purpose of the Study:
- To report 5-year efficacy, toxicity, and quality-of-life (QOL) outcomes of a novel 4-day SBRT regimen for prostate cancer.
- Evaluate the effectiveness of SBRT in low- and intermediate-risk PC patients.
Main Methods:
- A single-arm prospective phase 2 trial involving 259 patients with low- or intermediate-risk PC.
- Treatment involved SBRT with 38Gy in four fractions, mimicking HDR brachytherapy dosimetry.
- Median follow-up was 5 years, with assessments of biochemical recurrence (BCR), toxicity, and QOL.
Main Results:
- 5-year BCR-free rates were 100% for low-risk and 88.5% for intermediate-risk PC.
- Cumulative 5-year toxicity rates were low: 12.4% urinary and 3.4% gastrointestinal (grade 2+).
- Prostate-specific antigen (PSA) levels significantly decreased, and QOL returned to baseline by 6 months, with some late urinary domain decline.
Conclusions:
- The 4-day SBRT regimen yields high BCR-free survival and a low PSA nadir, suggesting prostate ablation.
- This SBRT regimen is effective for selected patients with low- or intermediate-risk prostate cancer.
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