A method of incorporating organ motion uncertainties into three-dimensional conformal treatment plans Journal Article


Authors: Mageras, G. S.; Kutcher, G. J.; Leibel, S. A.; Zelefsky, M. J.; Melian, E.; Mohan, R.; Fuks, Z.
Article Title: A method of incorporating organ motion uncertainties into three-dimensional conformal treatment plans
Abstract: Purpose: We describe a method of incorporating organ motion into three-dimensional (3D) conformal treatment plans, which predicts the effect of organ motion on the calculated dose to both the clinical target volume (CTV) and nontarget organs. Methods and Materials: The method is based on measurements of organ motion by means of multiple computed tomography (CT) scans from a group of "reference" patients, in which the data consist of previously drawn contours of the target and nontarget organs. A computer program records the differences in contour position and shape that occur between scans in the reference data, and according to those differences adjusts the contours and dose calculation points of a "study" patient currently being planned, thus simulating organ motion. Dose-volume histograms (DVHs) are accumulated, and the process is repeated over the set of reference patient scans, resulting in a set of treatment plans that are ranked according to a dose-based endpoint. Two plans are selected corresponding to specified lower and upper confidence limits in the endpoint, and the DVHs from these plans are displayed for comparison with the DVHs from the nominal plan in the absence of motion. Results: As an example of the method's use, it is applied to a 6-field conformal treatment plan for prostate cancer. Confidence limit DVHs of the CTV and rectal wall (in which the plans were ranked by probabilities for tumor control and normal tissue complication, respectively) are presented and compared to those from the nominal plan. Conclusion: The method provides a means of estimating the uncertainty in dose delivered by a treatment plan when organ motion is present. It is generally applicable to any treatment site for which data in the form of multiple CT scans are available, and can be extended to include other treatment uncertainties such as variation in patient positioning.
Keywords: treatment planning; radiation dose; computer assisted tomography; tumor volume; radiotherapy dosage; prostate cancer; prostatic neoplasms; algorithm; three dimensional imaging; artifact; radiotherapy planning, computer-assisted; patient positioning; computer assisted radiotherapy; computer program; histogram; movement; organ motion; prostate radiotherapy; humans; human; male; priority journal; article; conformal therapy; computerized 3d treatment planning
Journal Title: International Journal of Radiation Oncology, Biology, Physics
Volume: 35
Issue: 2
ISSN: 0360-3016
Publisher: Elsevier Inc.  
Date Published: 1996-05-01
Start Page: 333
End Page: 342
Language: English
DOI: 10.1016/0360-3016(96)00008-9
PUBMED: 8635941
PROVIDER: scopus
DOI/URL:
Notes: Article -- Export Date: 22 November 2017 -- Source: Scopus
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MSK Authors
  1. Zvi Fuks
    427 Fuks
  2. Michael J Zelefsky
    754 Zelefsky
  3. Steven A Leibel
    252 Leibel
  4. Gerald J Kutcher
    106 Kutcher
  5. Gikas S Mageras
    277 Mageras
  6. Radhe   Mohan
    97 Mohan