Image-guided Intensity-modulated Radiotherapy for Prostate Cancer Employing Hypofractionation and Simultaneous Integrated Boost: Results of a Consecutive Case Series with Focus on Erectile Function

Aim: To report on clinical outcomes of prostate cancer patients treated with hypofractionated radiotherapy employing a simultaneous integrated boost strategy.

Patients and methods: A consecutive series of 104 patients affected with prostate cancer was treated with intensity-modulated radiotherapy using a hypofractionated schedule and a simultaneous integrated boost consisting of 70 Gy (2.5 Gy daily) to the prostate gland, 63 Gy to the seminal vesicles (2.25 Gy daily) and 53.2 Gy to the pelvic nodes (1.9 Gy daily) when needed, delivered in 28 fractions. All patients underwent image-guided radiotherapy procedure consisting of daily cone-beam computed tomography.

Results: After a median observation time of 26 (range=15-48) months, the 3-year biochemical failure-free survival was 96.5% [95% confidence interval (CI)=89%-98%], 3-year cancer-specific survival was 98.5% (95% CI=91%-99%) and 3-year overall survival was 96.5% (95% CI=89%-98%). The gastrointestinal and genitourinary toxicity profiles were mild with fewer than 2% of grade 3 events. Erectile function was partially affected by radiation in men potent at baseline.

Conclusion: Hypofractionation delivered with intensity-modulated radiotherapy and a simultaneous integrated boost approach proved to be a safe and effective treatment option for patients with prostate cancer. Patients with a preserved baseline erectile function experience a decrease in functionality correlated with the mean dose received by penile bulb.