Two Years’ Experience with Stereotactic Body Radiotherapy for Localized Prostate Cancer Using the CyberKnife System

Objectives: : evaluating clinical outcomes and toxicity for newly implemented SBRT for localized prostate cancer using cyberknife in 57357 hospital.

Methods: : Data were collected form Fifty-one prostate cancer patients who were treated with Cyberknife at Children’s Cancer Hospital Egypt between August 2022 and August 2024. All patients received a prescribed radiation dose of 36.25 Gy in 5 fractions, delivered every other day. Four golden fiducials marks were implanted in each patient using trans rectal ultrasound 12 days prior CT simulation for motion tracking during treatment. Treatment plans were designed using MLC collimator and the dose constraints to critical organs met the RTOG criteria. Patient specific quality assurance was performed for each patient.

Results: : Treatment plans were designed using MLC collimator with the dose prescribed to 88 %-90% of maximum dose, and the dose constraints to critical organs met the RTOG criteria. Patient – Specific Quality Assurance were maintained at 3% differences between measured and calculated dose. The average treatment delivery time was 17 minutes ± 2 minutes.23 patients were of high risk while 22 and 6 were with intermediate and low risk respectively. Concomitant hormonal treatment was given according to risk classification. 11 out of the 51 developed grade 1 lower GIT toxicity while 9 developed grade 1 GU toxicity. The rest developed no toxicity. Till last day of follow up, all were free of disease with normal PSA.

Conclusion(s):: Successful implementation of SBRT for localized prostate cancer using Cyberknife at our department. Our two-years’ experience demonstrated that ultrahypofractionation was well tolerated with good local control and tolerable toxicity.