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The impact of respiratory motion and treatment technique on stereotactic body radiation therapy for liver cancer.

Publication ,  Journal Article
Wu, QJ; Thongphiew, D; Wang, Z; Chankong, V; Yin, F-F
Published in: Med Phys
April 2008

Stereotactic body radiation therapy (SBRT), which delivers a much higher fractional dose than conventional treatment in only a few fractions, is an effective treatment for liver metastases. For patients who are treated under free-breathing conditions, however, respiration-induced tumor motion in the liver is a concern. Limited clinical information is available related to the impact of tumor motion and treatment technique on the dosimetric consequences. This study evaluated the dosimetric deviations between planned and delivered SBRT dose in the presence of tumor motion for three delivery techniques: three-dimensional conformal static beams (3DCRT), dynamic conformal arc (DARC), and intensity-modulated radiation therapy (IMRT). Five cases treated with SBRT for liver metastases were included in the study, with tumor motions ranging from 0.5 to 1.75 cm. For each case, three different treatment plans were developed using 3DCRT, DARC, and IMRT. The gantry/multileaf collimator (MLC) motion in the DARC plans and the MLC motion in the IMRT plans were synchronized to the patient's respiratory motion. Retrospectively sorted four-dimensional computed tomography image sets were used to determine patient-organ motion and to calculate the dose delivered during each respiratory phase. Deformable registration, using thin-plate-spline models, was performed to encode the tumor motion and deformation and to register the dose-per-phase to the reference phase images. The different dose distributions resulting from the different delivery techniques and motion ranges were compared to assess the effect of organ motion on dose delivery. Voxel dose variations occurred mostly in the high gradient regions, typically between the target volume and normal tissues, with a maximum variation up to 20%. The greatest CTV variation of all the plans was seen in the IMRT technique with the largest motion range (D99: -8.9%, D95: -8.3%, and D90: -6.3%). The greatest variation for all 3DCRT plans was less than 2% for D95. Dose variations for DARC fell between the 3DCRT and IMRT techniques. The dose volume histogram variations for normal organs were negligible. Therefore, the IMRT technique may be a preferable treatment choice in cases where the target volume and critical organs are in close proximity, or when normal organ protection is a high priority, provided that motion effect for the target volume can be managed.

Duke Scholars

Published In

Med Phys

DOI

ISSN

0094-2405

Publication Date

April 2008

Volume

35

Issue

4

Start / End Page

1440 / 1451

Location

United States

Related Subject Headings

  • Sensitivity and Specificity
  • Respiratory Mechanics
  • Reproducibility of Results
  • Radiotherapy Planning, Computer-Assisted
  • Radiotherapy Dosage
  • Radiosurgery
  • Radiometry
  • Nuclear Medicine & Medical Imaging
  • Movement
  • Liver Neoplasms
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Wu, Q. J., Thongphiew, D., Wang, Z., Chankong, V., & Yin, F.-F. (2008). The impact of respiratory motion and treatment technique on stereotactic body radiation therapy for liver cancer. Med Phys, 35(4), 1440–1451. https://doi.org/10.1118/1.2839095
Wu, Q Jackie, Danthai Thongphiew, Zhiheng Wang, Vira Chankong, and Fang-Fang Yin. “The impact of respiratory motion and treatment technique on stereotactic body radiation therapy for liver cancer.Med Phys 35, no. 4 (April 2008): 1440–51. https://doi.org/10.1118/1.2839095.
Wu QJ, Thongphiew D, Wang Z, Chankong V, Yin F-F. The impact of respiratory motion and treatment technique on stereotactic body radiation therapy for liver cancer. Med Phys. 2008 Apr;35(4):1440–51.
Wu, Q. Jackie, et al. “The impact of respiratory motion and treatment technique on stereotactic body radiation therapy for liver cancer.Med Phys, vol. 35, no. 4, Apr. 2008, pp. 1440–51. Pubmed, doi:10.1118/1.2839095.
Wu QJ, Thongphiew D, Wang Z, Chankong V, Yin F-F. The impact of respiratory motion and treatment technique on stereotactic body radiation therapy for liver cancer. Med Phys. 2008 Apr;35(4):1440–1451.

Published In

Med Phys

DOI

ISSN

0094-2405

Publication Date

April 2008

Volume

35

Issue

4

Start / End Page

1440 / 1451

Location

United States

Related Subject Headings

  • Sensitivity and Specificity
  • Respiratory Mechanics
  • Reproducibility of Results
  • Radiotherapy Planning, Computer-Assisted
  • Radiotherapy Dosage
  • Radiosurgery
  • Radiometry
  • Nuclear Medicine & Medical Imaging
  • Movement
  • Liver Neoplasms