[Stereotactic Body Radiotherapy of Prostate Cancer - Effectiveness and Toxicity]

Prostate cancer is the most prevalent cancer in males and its incidence is steadily increasing. Most cases of prostate cancer are diagnosed during the early asymptomatic period, in which case the prognosis is very good. Therapies differ widely in their efficacies and toxicities, and this is an important consideration when it comes to deciding which treatment is optimal for a particular patient. One treatment method for early stage prostate cancer is stereotactic body radiotherapy (SBRT). We present the first results obtained using this modality at our institution.

A total of 261 patients with low or intermediate risk prostate cancer were treated with SBRT between August 2010 and July 2012. Patients received a total dose of 36.25 Gy in five fractions of 7.25 Gy every other day. The toxicity of the treatment was evaluated according to RTOG criteria. For assessment of quality of life, patients filled out a modified EPIC questionnaire (Expanded Prostate Composite index).

Overall survival (OS) in this study was 93.1%. Biochemical relapse free survival (bRFS) was 97.7%. As expected, OS and bRFS were worse in the group of patients with an intermediate risk of recurrence. Acute and chronic urinary and gastrointestinal RTOG toxicity was very low. Quality of life after treatment, as determined using the EPIC questionnaire, was slightly reduced immediately after treatment but returned to baseline or even improved during long term follow-up.

SBRT is an effective therapeutic modality for early prostate cancer and has acceptable rates of acute and low late toxicity.Key words: prostate cancer - stereotactic body radiotherapy - quality of life The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 5. 1. 2017Accepted: 1. 2. 2017.