Aims: High dose rate (HDR) brachytherapy offers a highly conformal approach to radiotherapy delivery, enabling dose escalation. We report our experience using a combined HDR boost and external beam radiotherapy (EBRT) approach and its associated toxicity and effect on quality of life.
Materials and methods: Patients with intermediate- or high-risk prostate cancer were treated with a single fraction HDR boost and EBRT between July 2008 and March 2010. Patient-reported toxicity data were collected at baseline and regular intervals after radiotherapy using International Prostate Symptom Score and Late Effects in Normal Tissues-Subjective, Objective, Management and Analytic scales (LENT-SOMA) questionnaires; health-related quality of life data were captured by the Expanded Prostate Cancer Index Composite (EPIC) questionnaire.
Results: Ninety-five patients received an HDR boost of 12.5 Gy followed by EBRT delivered as 37.5 Gy in 15 fractions over 3 weeks. The International Prostate Symptom Score peaked 6 weeks after radiotherapy (median value: 9). The LENT-SOMA bladder/urethra mean baseline score was 0.35 and peaked 6 weeks after radiotherapy (mean = 0.59). Difficulties with urinary flow and frequency were the most common reported symptoms. LENT-SOMA rectum/bowel mean scores at baseline were 0.24 and peaked after 6 months (mean = 0.37). Bowel urgency was the most common reported toxicity. EPIC urinary scores returned to baseline values at 6 months and bowel median scores recovered after 24 months. There were no statistically significant associations between patient or dosimetric parameters and patient-reported outcomes.
Conclusion: A combined HDR boost and hypofractionated EBRT regimen offers a well-tolerated method of dose escalation with acceptable levels of patient-reported toxicity.
Keywords: Brachytherapy; hypofractionation; patient-reported toxicity; prostate.
Copyright © 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.