[Feasibility and toxicity of a single fraction high-dose-rate brachytherapy followed by a course of EBRT for localized prostate cancer: a retrospective study. The Polyclinique Courlancy experience].

PURPOSE

Evaluate the feasibility and toxicity of radiation dose escalation delivered with a single fraction high-dose-rate (HDR) brachytherapy boost followed by external beam radiotherapy for intermediate and high risk localized prostate cancer - a retrospective study.

PATIENTS AND METHODS

Between December 2004 and December 2008, 61 patients with intermediate risk or high-risk localized prostate cancer received a single 10 Gy fraction of interstitial HDR brachytherapy followed by a 64 Gy course of external beam radiation therapy. Dose volume histograms, conformity index and side effects were systematically analyzed.

RESULTS

HDR brachytherapy dosimetric criteria were respected. Early side effects (< or = 3 months after full treatment): 30 % reported grade 2 or grade 3 urinary toxicity and 26 % reported grade 2 or grade 3 bowel toxicity were reported. Late side effects (> 3 months): 12 % reported grade 2 or grade 3 urinary toxicity and 5 % reported grade 2 or grade 3 bowel toxicity were reported. No patients reported any grade 4 late toxicity events. Three months after treatment, 7 % grade 1, 25 % grade 2 and 39 % grade 3 erectile dysfunction were reported.

CONCLUSION

Our monofractionation protocol is an easy technique to implement logistically. Acute and late toxicities are acceptable and comparable to those published by various teams mostly using multifractionation protocols. A longer follow-up is required to assess the effect of this dose escalation protocol on long-term biological control.