Dataset Information

Image-guided radiotherapy reduces the risk of under-dosing high-risk prostate cancer extra-capsular disease and improves biochemical control.

ABSTRACT:

Background

To determine if reduced dose delivery uncertainty is associated with daily image-guidance (IG) and Prostate Specific Antigen Relapse Free Survival (PRFS) in intensity-modulated radiotherapy (IMRT) of high-risk prostate cancer (PCa).

Methods

Planning data for consecutive PCa patients treated with IMRT (n?=?67) and IG-IMRT (n?=?35) was retrieved. Using computer simulations of setup errors, we estimated the patient-specific uncertainty in accumulated treatment dose distributions for the prostate and for posterolateral aspects of the gland that are at highest risk for extra-capsular disease. Multivariate Cox regression for PRFS considering Gleason score, T-stage, pre-treatment PSA, number of elevated clinical risk factors (T2c+, GS7+ and PSA10+), nomogram-predicted risk of extra-capsular disease (ECD), and dose metrics was performed.

Results

For IMRT vs. IG-IMRT, plan dosimetry values were similar, but simulations revealed uncertainty in delivered dose external to the prostate was significantly different, due to positioning uncertainties. A patient-specific interaction term of the risk of ECD and risk of low dose to the ECD (p?=?0.005), and the number of elevated clinical risk factors (p?=?0.008), correlate with reduced PRFS.

Conclusions

Improvements in PSA outcomes for high-risk PCa using IG-IMRT vs. IMRT without IG may be due to improved dosimetry for ECD.

SUBMITTER: Munck Af Rosenschold P

PROVIDER: S-EPMC5898030 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Publications

Image-guided radiotherapy reduces the risk of under-dosing high-risk prostate cancer extra-capsular disease and improves biochemical control.

Munck Af Rosenschold Per P Zelefsky Michael J MJ Apte Aditya P AP Jackson Andrew A Oh Jung Hun JH Shulman Elliot E Desai Neil N Hunt Margie M Ghadjar Pirus P Yorke Ellen E Deasy Joseph O JO

Radiation oncology (London, England) 20180412 1

<h4>Background</h4>To determine if reduced dose delivery uncertainty is associated with daily image-guidance (IG) and Prostate Specific Antigen Relapse Free Survival (PRFS) in intensity-modulated radiotherapy (IMRT) of high-risk prostate cancer (PCa).<h4>Methods</h4>Planning data for consecutive PCa patients treated with IMRT (n = 67) and IG-IMRT (n = 35) was retrieved. Using computer simulations of setup errors, we estimated the patient-specific uncertainty in accumulated treatment dose distrib ...[more]

PMID: 29650035

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Dataset Information

Image-guided radiotherapy reduces the risk of under-dosing high-risk prostate cancer extra-capsular disease and improves biochemical control.

Background

Methods

Results

Conclusions

Publications

Image-guided radiotherapy reduces the risk of under-dosing high-risk prostate cancer extra-capsular disease and improves biochemical control.

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