This work has been submitted for presentation at ASTRO's annual meeting 2013
Comparison of high-dose (86.4 Gy) IMRT vs combined brachytherapy plus IMRT for intermediate-risk prostate cancer
Article first published online: 22 JAN 2014
© 2013 The Authors. BJU International © 2013 BJU International
Volume 114, Issue 3, pages 360–367, September 2014
How to Cite
Spratt, D. E., Zumsteg, Z. S., Ghadjar, P., Kollmeier, M. A., Pei, X., Cohen, G., Polkinghorn, W., Yamada, Y. and Zelefsky, M. J. (2014), Comparison of high-dose (86.4 Gy) IMRT vs combined brachytherapy plus IMRT for intermediate-risk prostate cancer. BJU International, 114: 360–367. doi: 10.1111/bju.12514
- Issue published online: 25 AUG 2014
- Article first published online: 22 JAN 2014
- Accepted manuscript online: 15 OCT 2013 10:20AM EST
- intensity-modulated radiotherapy;
- distant metastases
- To compare tumour control and toxicity outcomes with the use of high-dose intensity-modulated radiation therapy (IMRT) alone or brachytherapy combined with IMRT (combo-RT) for patients with intermediate-risk prostate cancer.
Patients and Methods
- Between 1997 and 2010, 870 consecutive patients with intermediate-risk prostate cancer were treated at our institution with either 86.4 Gy of IMRT alone (n = 470) or combo-RT consisting of brachytherapy combined with 50.4 Gy of IMRT (n = 400).
- Brachytherapy consisted of low-dose-rate permanent interstitial implantation in 260 patients and high-dose-rate temporary implantation in 140 patients.
- The median (range) follow-up for the entire cohort was 5.3 (1–14) years.
- For IMRT alone vs combo-RT, 7-year actuarial prostate-specific antigen (PSA)-relapse-free survival (PSA-RFS) rates were 81.4 vs 92.0% (P < 0.001), and distant metastases-free survival (DMFS) rates were 93.0 vs 97.2% (P = 0.04), respectively.
- Multivariate analysis showed that combo-RT was associated with better PSA-RFS (hazard ratio [HR], 0.40 [95% confidence interval, 0.24–0.66], P < 0.001), and better DMFS (HR, 0.41 [0.18–0.92], P = 0.03).
- A higher incidence of acute genitourinary (GU) grade 2 (35.8 vs 18.9%; P < 0.01) and acute GU grade 3 (2.3 vs 0.4%; P = 0.03) toxicities occurred in the combo-RT group than in the IMRT-alone group. Most acute toxicity resolved. Late toxicity outcomes were similar between the treatment groups. The 7-year actuarial late toxicity rates for grade 2 gastrointestinal (GI) toxicity were 4.6 vs 4.1% (P = 0.89), for grade 3 GI toxicity 0.4 vs 1.4% (P = 0.36), for grade 2 GU toxicity 19.4 vs 21.2% (P = 0.14), and grade 3 GU toxicity 3.1 vs 1.4% (P = 0.74) for the IMRT vs the combo-RT group, respectively.
- Enhanced dose escalation using combo-RT was associated with superior PSA-RFS and DMFS outcomes for patients with intermediate-risk prostate cancer compared with high-dose IMRT alone at a dose of 86.4 Gy.
- While acute GU toxicities were more prevalent in the combo-RT group, the incidence of late GI and GU toxicities was similar between the treatment groups.