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Dose accumulation with deformable image registration method using helical tomotherapy images for prostate cancer

Published online by Cambridge University Press:  06 June 2019

Warit Thongsuk
Affiliation:
Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand Graduate School, Chiang Mai University, Chiang Mai, Thailand
Imjai Chitapanarux*
Affiliation:
Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
Somsak Wanwilairat
Affiliation:
Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
Wannapha Nobnop
Affiliation:
Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
*
Author for correspondence: Imjai Chitapanarux, Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chiang Mai University, 110 Intavaroros Rd., Sriphum 50200, Chiang Mai, Thailand. Tel: 66 53935456. Email: imjai@hotmail.com

Abstract

Purpose:

To evaluate changes of accumulated doses from an initial plan in each fraction by deformable image registration (DIR) with daily megavoltage computed tomography (MVCT) images from helical tomotherapy for prostate cancer patients.

Materials and methods:

The MVCT images of five prostate cancer patients were acquired by using a helical tomotherapy unit before the daily treatment fraction began. All images data were exported to DIR procedures by MIM software, in which the planned kilovoltage computed tomography (kVCT) images were acting as the source images with the daily MVCT acquired as the target images for registration. The automatic deformed structure was used to access the volume variation and daily dose accumulation to each structure. All dose-volume parameters were compared to the initial planned dose.

Results:

The actual median doses of the planning target volume (PTV) received 70 Gy and 50.4 Gy were decreased at the end of the treatment with an average 1·0 ± 0·67% and 2·1 ± 1·54%, respectively. As regards organs at risk (OARs), the bladder and rectum dose-volume parameters tended to increase from the initial plan. The high-dose regions of the bladder and rectum, however, were decreased from the initial plan at the end of the treatment.

Conclusions:

The daily actual dose differs from the initial planned dose. The accumulated dose of target tends to be lower than the initial plan, but tends to be higher than the initial plan for the OARs. Therefore, inter-fractional anatomic changes should be considered by the DIR methods, which would be useful as clinically informative and beneficial for adaptive treatment strategies.

Type
Original Article
Copyright
© Cambridge University Press 2019 

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References

Yartsev, S, Kron, T, Van Dyk, J. Tomotherapy as a tool in image-guided radiation therapy (IGRT): theoretical and technological aspects. Biomed Imaging Interv J. 2007; 3(1): e16.Google ScholarPubMed
Huang, E, Dong, L Chandra, A, et al. Intrafraction prostate motion during IMRT for prostate cancer. Int J Radiat Oncol Biol Phys. 2002; 53: 261268.CrossRefGoogle ScholarPubMed
Wu, J, Haycocks, T, Alasti, H, et al. Positioning errors and prostate motion during conformal prostate radiotherapy using on-line isocentre set-up verification and implanted prostate markers. Radiother Oncol. 2001; 61: 127133.CrossRefGoogle ScholarPubMed
Oh, S, Kim, S. Deformable image registration in radiation therapy. Radiat Oncol J. 2017; 35(2): 101111.CrossRefGoogle ScholarPubMed
Lee, WR, Dignam, JJ, Amin, M, et al. NRG oncology RTOG 0415: a randomized phase III non-inferiority study comparing two fractionation schedules in patients with low-risk prostate cancer. Int J Radiat Oncol Biol Phys. 2016; 94(1): 34.CrossRefGoogle Scholar
Broggi, S, Scalco, E, Belli, ML, et al. A comparative evaluation of 3 different free-form deformable image registration and contour propagation methods for head and neck MRI: the case of parotid changes during radiotherapy. Technol Cancer Res Treat. 2017; 16(3): 373381.CrossRefGoogle ScholarPubMed
Pinkawa, M, Asadpour, B, Gagel, B, Piroth, MD, Holy, R, Eble, MJ. Prostate position variability and dose-volume histograms in radiotherapy for prostate cancer with full and empty bladder. Int J Radiat Oncol Biol Phys. 2006; 64: 856861.CrossRefGoogle ScholarPubMed
Godley, A, Ahunbay, E, Peng, C, Li, XA. Accumulating daily-varied dose distributions of prostate radiation therapy with soft-tissue-based kV CT guidance. J Appl Clin Med Phys. 2012; 13(3): 98107.CrossRefGoogle ScholarPubMed