Rectal dose variation during the course of image-guided radiation therapy of prostate cancer

Lili Chen, Kamen Paskalev, Xiu Xu, Jennifer Zhu, Lu Wang, Robert A. Price, Wei Hu, Steven J. Feigenberg, Eric M. Horwitz, Alan Pollack, C. M Charlie Ma

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

Background and purpose: To investigate the change in rectal dose during the treatment course for intensity- modulated radiotherapy (IMRT) of prostate cancer with image-guidance. Materials and methods: Twenty prostate cancer patients were recruited for this retrospective study. All patients have been treated with IMRT. For each patient, MR and CT images were fused for target and critical structure delineation. IMRT treatment planning was performed on the simulation CT images. Interfractional motion during the course of treatment was corrected using a CT-on-rails system. The rectum was outlined on both the original treatment plan and the subsequent daily CT images from the T-onrails by the same investigator. Dose distributions on these daily CT images were recalculated with the isocenter shifts relative to the simulation CT images using the leaf sequences/MUs based on the original treatment plan. The rectal doses from the subsequent daily CTs were compared with the original doses planned on the simulation CT using our clinical acceptance criteria. Results: Based on 20 patients with 139 daily CT sets, 28% of the subsequent treatment dose distributions did not meet our criterion of V 40 < 35%, and 27% did not meet our criterion of V 65 < 17%. The inter-fractional rectal volume variation is significant for some patients. Conclusions: Due to the large inter-fractional variation of the rectal volume, it is more favorable to plan prostate IMRT based on an empty rectum and deliver treatment to patients with an empty rectum. Over 70% of actual treatments showed better rectal doses than our clinical acceptance criteria. A significant fraction (27%) of the actual treatments would benefit from adaptive image-guided radiotherapy based on daily CT images.

Original languageEnglish
Pages (from-to)198-202
Number of pages5
JournalRadiotherapy and Oncology
Volume95
Issue number2
DOIs
StatePublished - May 1 2010
Externally publishedYes

Fingerprint

Image-Guided Radiotherapy
Prostatic Neoplasms
Intensity-Modulated Radiotherapy
Rectum
Therapeutics
Prostate
Retrospective Studies
Research Personnel

Keywords

  • Course of treatment
  • IGRT
  • Prostate IMRT
  • Radiotherapy
  • Rectal dose

ASJC Scopus subject areas

  • Oncology
  • Radiology Nuclear Medicine and imaging
  • Hematology
  • Medicine(all)

Cite this

Chen, L., Paskalev, K., Xu, X., Zhu, J., Wang, L., Price, R. A., ... Ma, C. M. C. (2010). Rectal dose variation during the course of image-guided radiation therapy of prostate cancer. Radiotherapy and Oncology, 95(2), 198-202. https://doi.org/10.1016/j.radonc.2010.02.023

Rectal dose variation during the course of image-guided radiation therapy of prostate cancer. / Chen, Lili; Paskalev, Kamen; Xu, Xiu; Zhu, Jennifer; Wang, Lu; Price, Robert A.; Hu, Wei; Feigenberg, Steven J.; Horwitz, Eric M.; Pollack, Alan; Ma, C. M Charlie.

In: Radiotherapy and Oncology, Vol. 95, No. 2, 01.05.2010, p. 198-202.

Research output: Contribution to journalArticle

Chen, L, Paskalev, K, Xu, X, Zhu, J, Wang, L, Price, RA, Hu, W, Feigenberg, SJ, Horwitz, EM, Pollack, A & Ma, CMC 2010, 'Rectal dose variation during the course of image-guided radiation therapy of prostate cancer', Radiotherapy and Oncology, vol. 95, no. 2, pp. 198-202. https://doi.org/10.1016/j.radonc.2010.02.023
Chen, Lili ; Paskalev, Kamen ; Xu, Xiu ; Zhu, Jennifer ; Wang, Lu ; Price, Robert A. ; Hu, Wei ; Feigenberg, Steven J. ; Horwitz, Eric M. ; Pollack, Alan ; Ma, C. M Charlie. / Rectal dose variation during the course of image-guided radiation therapy of prostate cancer. In: Radiotherapy and Oncology. 2010 ; Vol. 95, No. 2. pp. 198-202.
@article{1e0cac5758994b779622a084005b8df8,
title = "Rectal dose variation during the course of image-guided radiation therapy of prostate cancer",
abstract = "Background and purpose: To investigate the change in rectal dose during the treatment course for intensity- modulated radiotherapy (IMRT) of prostate cancer with image-guidance. Materials and methods: Twenty prostate cancer patients were recruited for this retrospective study. All patients have been treated with IMRT. For each patient, MR and CT images were fused for target and critical structure delineation. IMRT treatment planning was performed on the simulation CT images. Interfractional motion during the course of treatment was corrected using a CT-on-rails system. The rectum was outlined on both the original treatment plan and the subsequent daily CT images from the T-onrails by the same investigator. Dose distributions on these daily CT images were recalculated with the isocenter shifts relative to the simulation CT images using the leaf sequences/MUs based on the original treatment plan. The rectal doses from the subsequent daily CTs were compared with the original doses planned on the simulation CT using our clinical acceptance criteria. Results: Based on 20 patients with 139 daily CT sets, 28{\%} of the subsequent treatment dose distributions did not meet our criterion of V 40 < 35{\%}, and 27{\%} did not meet our criterion of V 65 < 17{\%}. The inter-fractional rectal volume variation is significant for some patients. Conclusions: Due to the large inter-fractional variation of the rectal volume, it is more favorable to plan prostate IMRT based on an empty rectum and deliver treatment to patients with an empty rectum. Over 70{\%} of actual treatments showed better rectal doses than our clinical acceptance criteria. A significant fraction (27{\%}) of the actual treatments would benefit from adaptive image-guided radiotherapy based on daily CT images.",
keywords = "Course of treatment, IGRT, Prostate IMRT, Radiotherapy, Rectal dose",
author = "Lili Chen and Kamen Paskalev and Xiu Xu and Jennifer Zhu and Lu Wang and Price, {Robert A.} and Wei Hu and Feigenberg, {Steven J.} and Horwitz, {Eric M.} and Alan Pollack and Ma, {C. M Charlie}",
year = "2010",
month = "5",
day = "1",
doi = "10.1016/j.radonc.2010.02.023",
language = "English",
volume = "95",
pages = "198--202",
journal = "Radiotherapy and Oncology",
issn = "0167-8140",
publisher = "Elsevier Ireland Ltd",
number = "2",

}

TY - JOUR

T1 - Rectal dose variation during the course of image-guided radiation therapy of prostate cancer

AU - Chen, Lili

AU - Paskalev, Kamen

AU - Xu, Xiu

AU - Zhu, Jennifer

AU - Wang, Lu

AU - Price, Robert A.

AU - Hu, Wei

AU - Feigenberg, Steven J.

AU - Horwitz, Eric M.

AU - Pollack, Alan

AU - Ma, C. M Charlie

PY - 2010/5/1

Y1 - 2010/5/1

N2 - Background and purpose: To investigate the change in rectal dose during the treatment course for intensity- modulated radiotherapy (IMRT) of prostate cancer with image-guidance. Materials and methods: Twenty prostate cancer patients were recruited for this retrospective study. All patients have been treated with IMRT. For each patient, MR and CT images were fused for target and critical structure delineation. IMRT treatment planning was performed on the simulation CT images. Interfractional motion during the course of treatment was corrected using a CT-on-rails system. The rectum was outlined on both the original treatment plan and the subsequent daily CT images from the T-onrails by the same investigator. Dose distributions on these daily CT images were recalculated with the isocenter shifts relative to the simulation CT images using the leaf sequences/MUs based on the original treatment plan. The rectal doses from the subsequent daily CTs were compared with the original doses planned on the simulation CT using our clinical acceptance criteria. Results: Based on 20 patients with 139 daily CT sets, 28% of the subsequent treatment dose distributions did not meet our criterion of V 40 < 35%, and 27% did not meet our criterion of V 65 < 17%. The inter-fractional rectal volume variation is significant for some patients. Conclusions: Due to the large inter-fractional variation of the rectal volume, it is more favorable to plan prostate IMRT based on an empty rectum and deliver treatment to patients with an empty rectum. Over 70% of actual treatments showed better rectal doses than our clinical acceptance criteria. A significant fraction (27%) of the actual treatments would benefit from adaptive image-guided radiotherapy based on daily CT images.

AB - Background and purpose: To investigate the change in rectal dose during the treatment course for intensity- modulated radiotherapy (IMRT) of prostate cancer with image-guidance. Materials and methods: Twenty prostate cancer patients were recruited for this retrospective study. All patients have been treated with IMRT. For each patient, MR and CT images were fused for target and critical structure delineation. IMRT treatment planning was performed on the simulation CT images. Interfractional motion during the course of treatment was corrected using a CT-on-rails system. The rectum was outlined on both the original treatment plan and the subsequent daily CT images from the T-onrails by the same investigator. Dose distributions on these daily CT images were recalculated with the isocenter shifts relative to the simulation CT images using the leaf sequences/MUs based on the original treatment plan. The rectal doses from the subsequent daily CTs were compared with the original doses planned on the simulation CT using our clinical acceptance criteria. Results: Based on 20 patients with 139 daily CT sets, 28% of the subsequent treatment dose distributions did not meet our criterion of V 40 < 35%, and 27% did not meet our criterion of V 65 < 17%. The inter-fractional rectal volume variation is significant for some patients. Conclusions: Due to the large inter-fractional variation of the rectal volume, it is more favorable to plan prostate IMRT based on an empty rectum and deliver treatment to patients with an empty rectum. Over 70% of actual treatments showed better rectal doses than our clinical acceptance criteria. A significant fraction (27%) of the actual treatments would benefit from adaptive image-guided radiotherapy based on daily CT images.

KW - Course of treatment

KW - IGRT

KW - Prostate IMRT

KW - Radiotherapy

KW - Rectal dose

UR - http://www.scopus.com/inward/record.url?scp=77956563265&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77956563265&partnerID=8YFLogxK

U2 - 10.1016/j.radonc.2010.02.023

DO - 10.1016/j.radonc.2010.02.023

M3 - Article

C2 - 20303193

AN - SCOPUS:77956563265

VL - 95

SP - 198

EP - 202

JO - Radiotherapy and Oncology

JF - Radiotherapy and Oncology

SN - 0167-8140

IS - 2

ER -