Progress in Medical Physics (한국의학물리학회지:의학물리)

Korean Society of Medical Physics (한국의학물리학회)
권호 표지
DOI QR코드

DOI QR Code

Dosimetric Evaluation of Plans Converted with the DVH-Based Plan Converter

  • Chun, Minsoo (Department of Radiation Oncology, Seoul National University Hospital) ;
  • Choi, Chang Heon (Department of Radiation Oncology, Seoul National University Hospital) ;
  • Kim, Jung-in (Department of Radiation Oncology, Seoul National University Hospital) ;
  • Yoo, Jeongmin (Department of Radiation Oncology, Seoul National University Hospital) ;
  • Lee, Sung Young (Department of Radiation Oncology, Seoul National University Hospital) ;
  • Kwon, Ohyun (Department of Radiation Oncology, Seoul National University Hospital) ;
  • Son, Jaeman (Department of Radiation Oncology, Seoul National University Hospital) ;
  • An, Hyun Joon (Department of Radiation Oncology, Seoul National University Hospital) ;
  • Kang, Seong-Hee (Department of Radiation Oncology, Seoul National University Bundang Hospital) ;
  • Park, Jong Min (Department of Radiation Oncology, Seoul National University Hospital)
  • Received : 2018.11.28
  • Accepted : 2018.12.14
  • Published : 2018.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

Plans converted using dose-volume-histogram-based plan conversion (DPC) were evaluated by comparing them to the original plans. Changes in the dose volumetric (DV) parameters of five volumetric modulated arc therapy (VMAT) plans for head and neck (HN) cancer and five VMAT plans for prostate cancer were analyzed. For the HN plans, the homogeneity indices (HIs) of the three planning target volumes (PTV) increased by 0.03, 0.02, and 0.03, respectively, after DPC. The maximum doses to the PTVs increased by 1.20, 1.87, and 0.92 Gy, respectively, after DPC. The maximum doses to the optic chiasm, optic nerves, spinal cord, brain stem, lenses, and parotid glands increased after DPC by approximately 4.39, 3.62, 7.55, 7.96, 1.77, and 6.40 Gy, respectively. For the prostate plans after DPC, the HIs for the primary and boost PTVs increased by 0.05 and 0.03, respectively, and the maximum doses to each PTV increased by 1.84 and 0.19 Gy, respectively. After DPC, the mean doses to the rectum and femoral heads increased by approximately 6.19 and 2.79 Gy, respectively, and those to the bladder decreased by 0.20 Gy when summing the primary and boost plans. Because clinically unacceptable changes were sometimes observed after DPC, plans converted by DPC should be carefully reviewed before actual patient treatment.

Keywords

References

  1. Krishna GS, Srinivas V, Ayyangar K, Reddy PY. Comparative study of old and new versions of treatment planning system using dose volume histogram indices of clinical plans. J Med Phys. 2016;41(3):192. https://doi.org/10.4103/0971-6203.189489
  2. Hirata T, Kishi N, Imai Y, et al. Dose Volume Parameters as Predictors for Radiation-Induced Hypothyroidism After IMRT or VMAT for Head and Neck Squamous Cell Carcinoma: Comparison of the Availability Between Mean Thyroid Dose and Median Thyroid Dose. Int J Radiat Oncol Biol Phys. 2016;96(2):E365.
  3. Kim MY, Yu T, Wu H-G. Dose-volumetric parameters for predicting hypothyroidism after radiotherapy for head and neck cancer. Jpn J Clin Oncol. 2014;44(4):331-37. https://doi.org/10.1093/jjco/hyt235
  4. Park JM, Park S-Y, Choi CH, Chun M, Kim JH, Kim J-I. Treatment plan comparison between Tri-Co-60 magneticresonance image-guided radiation therapy and volumetric modulated arc therapy for prostate cancer. Oncotarget. 2017;8(53):91174.
  5. Treutwein M, Hipp M, Koelbl O, Dobler B. Searching standard parameters for volumetric modulated arc therapy (VMAT) of prostate cancer. Radiat Oncol. 2012;7(1):108. https://doi.org/10.1186/1748-717X-7-108
  6. Zulkafal H, Khan M, Ahmad M, Akram M, Buzdar S, Iqbal K. Volumetric modulated arc therapy treatment planning assessment for low-risk prostate cancer in radiotherapy. Clin Cancer Investig J. 2017;6(4):179-83. https://doi.org/10.4103/ccij.ccij_38_17
  7. Emami B, Lyman J, Brown A, et al. Tolerance of normal tissue to therapeutic irradiation. Int J Radiat Oncol Biol Phys. 1991;21(1):109-22.
  8. Lesperance RN, Kjorstadt RJ, Halligan JB, Steele SR. Colorectal complications of external beam radiation versus brachytherapy for prostate cancer. Am J Surg. 2008;195(5):616-20. https://doi.org/10.1016/j.amjsurg.2007.12.037
  9. Lawton CA, Michalski J, El-Naqa I, et al. RTOG GU Radiation oncology specialists reach consensus on pelvic lymph node volumes for high-risk prostate cancer. Int J Radiat Oncol Biol Phys. 2009;74(2):383-87. https://doi.org/10.1016/j.ijrobp.2008.08.002

Cited by

  1. A feasibility study of “plan transformation”: A novel workaround enabling patient transfer between different Varian machines vol.91, pp.None, 2018, https://doi.org/10.1016/j.ejmp.2021.10.002