Dataset Information

Comparison of dose decrement from intrafraction motion for prone and supine prostate radiotherapy.

ABSTRACT:

Background and purpose

Dose effects of intrafraction motion during prone prostate radiotherapy are unknown. We compared prone and supine treatment using real-time tracking data to model dose coverage.

Material and methods

Electromagnetic tracking data were analyzed for 10 patients treated prone, and 15 treated supine, with IMRT for localized prostate cancer. Plans were generated using 0 mm, 3 mm, and 5mm PTV expansions. Manual beam-hold interventions were applied to reposition the patient when translations exceeded a predetermined threshold. A custom software application (SWIFTER) used intrafraction tracking data acquired during beam-on model delivered prostate dose, by applying rigid body transformations to the prostate structure contoured at simulation within the planned dose cloud. The delivered minimum prostate dose as a percentage of planned dose (Dmin%), and prostate volume covered by the prescription dose as a percentage of the planned volume (VRx%) were compared for prone and supine treatment.

Results

Dmin% was reduced for prone treatment for 0 (p=0.02) and 3 mm (p=0.03) PTV margins. VRx% was reduced for prone treatment only for 0mm margins (p=0.002). No significant differences were found using 5 mm margins.

Conclusions

Intrafraction motion has a greater impact on target coverage for prone compared to supine prostate radiotherapy. PTV margins of 3 mm or less correlate with a significant decrease in delivered dose for prone treatment.

SUBMITTER: Olsen JR

PROVIDER: S-EPMC3423556 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature

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Publications

Comparison of dose decrement from intrafraction motion for prone and supine prostate radiotherapy.

Olsen Jeffrey R JR Parikh Parag J PJ Watts Michael M Noel Camille E CE Baker Kenneth W KW Santanam Lakshmi L Michalski Jeff M JM

Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology 20120717 2

<h4>Background and purpose</h4>Dose effects of intrafraction motion during prone prostate radiotherapy are unknown. We compared prone and supine treatment using real-time tracking data to model dose coverage.<h4>Material and methods</h4>Electromagnetic tracking data were analyzed for 10 patients treated prone, and 15 treated supine, with IMRT for localized prostate cancer. Plans were generated using 0 mm, 3 mm, and 5mm PTV expansions. Manual beam-hold interventions were applied to reposition the ...[more]

PMID: 22809590

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Dataset Information

Comparison of dose decrement from intrafraction motion for prone and supine prostate radiotherapy.

Background and purpose

Material and methods

Results

Conclusions

Publications

Comparison of dose decrement from intrafraction motion for prone and supine prostate radiotherapy.

Similar Datasets

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