The Journal of Korean Society for Radiation Therapy (대한방사선치료학회지)

Korean Society for Radiation Therapy (대한방사선치료학회)
권호 표지

The evaluation of properties for radiation therapy techniques with flattening filter-free beam and usefulness of time and economy to a patient with the radiation therapy

Flattening filter-free beam을 이용한 방사선 치료 기법의 특성 및 환자의 시간적.경제적 유용성 평가

  • Goo, Jang Hyeon (Department of Radiation Oncology, Seoul national university Bundang hospital) ;
  • Won, Hui Su (Department of Radiation Oncology, Seoul national university Bundang hospital) ;
  • Hong, Joo Wan (Department of Radiation Oncology, Seoul national university Bundang hospital) ;
  • Chang, Nam Jun (Department of Radiation Oncology, Seoul national university Bundang hospital) ;
  • Park, Jin Hong (Department of Radiation Oncology, Seoul national university Bundang hospital)
  • 구장현 (분당서울대학교병원 방사선종양학과) ;
  • 원희수 (분당서울대학교병원 방사선종양학과) ;
  • 홍주완 (분당서울대학교병원 방사선종양학과) ;
  • 장남준 (분당서울대학교병원 방사선종양학과) ;
  • 박진홍 (분당서울대학교병원 방사선종양학과)
  • Received : 2014.05.30
  • Accepted : 2014.12.02
  • Published : 2014.12.30
Download PDF
⟨ Previous Next ⟩

Abstract

Purpose : The aim of this study was to appraise properties for radiation therapy techniques and effectiveness of time and economy to a patient in the case of applying flattening filter-free (3F) and flattening filter (2F) beam to the radiation therapy. Materials and Methods : Alderson rando phantom was scanned for computed tomography image. Treatment plans for intensity modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT) and stereotactic body radiation therapy (SBRT) with 3F and 2F beam were designed for prostate cancer. To evaluate the differences between the 3F and 2F beam, total monitor units (MUs), beam on time (BOT) and gantry rotation time (GRT) were used and measured with $TrueBeam^{TM}$ STx and Surveillance And Measurement (SAM) 940 detector was used for photoneutron emitted by using 3F and 2F. To assess temporal and economical aspect for a patient, total treatment periods and medical fees were estimated. Results : In using 3F beam, total MUs in IMRT plan increased the highest up to 34.0% and in the test of BOT, GRT and photoneutron, the values in SBRT plan decreased the lowest 39.8, 38.6 and 48.1%, respectively. In the temporal and economical aspect, there were no differences between 3F and 2F beam in all of plans and the results showed that 10 days and 169,560 won was lowest in SBRT plan. Conclusion : According as the results, total MUs increased by using 3F beam than 2F beam but BOT, GRT and photoneutron decreased. From above the results, using 3F beam can decrease intra-fraction setup error and risk of radiation-induced secondary malignancy. But, using 3F beam did not make the benefits of temporal and economical aspect for a patient with the radiation therapy.

목 적 : Flattening filter-free (3F) beam과 flattening filter (2F) beam을 이용한 치료기법에 따른 특성 비교와 환자 측면의 시간적 경제적 유용성을 비교 평가하고자 한다. 대상 및 방법 : Alderson rando phantom의 전산화단층촬영 영상을 획득하여 가상의 전립선을 설정한 후 세기변조 방사선치료, 용적변조 회전방사선치료 그리고 체부정위적 방사선치료에 3F와 2F beam을 각각 적용하여 총 6개의 전산화치료계획을 수립하였다. 선량률은 3F beam을 이용한 치료기법에 1200 MU/min을 설정하였고, 2F beam의 경우 600 MU/min을 적용하였다. 3F와 2F beam을 이용한 치료기법의 특성 비교를 위하여 총 monitor unit (MU)값을 비교하였고 치료시간의 비교를 위하여 beam on time (BOT)과 gantry rotation time (GRT)을 측정하였으며, 3F와 2F beam에 의한 각 치료기법에서 발생되는 광중성자 측정을 위하여 Surveillance And Measurement (SAM) 940을 사용하였다. 또한, 환자의 총 내원기간과 자기부담금을 계산하였다. 결 과 : 총 MU값은 세기변조 방사선치료에서 3F beam을 이용하였을 때 2F beam을 이용한 경우보다 최대 34.0% 증가하였고 BOT, GRT 그리고 광중성자 측정값은 체부정위적 방사선치료에 3F beam을 적용하였을 때 2F beam보다 각각 최대 39.8, 38.6, 48.1% 감소하였다. 환자의 총 내원기간과 자기부담금은 3F와 2F beam의 이용에 따른 차이는 없었으며, 치료기법 중 체부정위적 방사선치료가 10일과 169,560원으로 가장 적게 나타났다. 결 론 : 본 연구 결과, 3F beam의 고 선량률을 이용한 치료기법은 2F beam과 비교하여 총 MU값은 증가하였으나 BOT, GRT 그리고 광중성자 측정값이 모두 감소하였다. 이처럼 3F beam의 고 선량률을 사용하는 치료기법은 intra-fraction setup error 및 2차 방사선 유발암 발생률을 줄이는 효과를 기대할 수 있으나, 동일한 치료기법 내에서 3F와 2F beam 사용에 따른 환자에게 특별한 시간적 경제적인 이점은 없었다.

Keywords

References

  1. Georg D, Kragl G, af Wetterstedt S, McCavana P, McClean B, Kns T. Photon beam quality variations of a flattening filter free linear accelerator. Med Phys 2010;37(1):49-53. https://doi.org/10.1118/1.3264617
  2. Purdy. J: Intensity-modulated radiation therapy: current status and issues of interest. Int J Radiat Oncol Biol Phys 2001; 51:880-914 https://doi.org/10.1016/S0360-3016(01)01749-7
  3. KRY, Stephen F. et al. Reduced Neutron Production Through Use of a Flattening-Filter-Free Accelerator. International Journal of Radiation Oncology* Biology* Physics, 2007, 68.4: 1260-1264. https://doi.org/10.1016/j.ijrobp.2007.04.002
  4. Zhao, B., et al. "SU C BRC 02: Plan Quality and Delivery Efficiency with Varian TrueBeam FFF Mode at High Dose Rate."Medical Physics 38.6 (2011): 3371- 3371.
  5. Kragl, Gabriele, et al. "Flattening filter free beams in SBRT and IMRT: dosimetric assessment of peripheral doses."Zeitschrift fur Medizinische Physik 21.2 (2011): 91-101. https://doi.org/10.1016/j.zemedi.2010.07.003
  6. Lohse, Ines, et al. "Effect of high dose per pulse flattening filter-free beams on cancer cell survival." Radiotherapy and Oncology 101.1 (2011): 226-232. https://doi.org/10.1016/j.radonc.2011.05.072
  7. Lechner, Wolfgang, Gabriele Kragl, and Dietmar Georg. "Evaluation of treatment plan quality of IMRT and VMAT with and without flattening filter using Pareto optimal fronts."Radiotherapy and Oncology 3 (2013): 437-441.
  8. Stathakis S, Esquivel C, Gutierrez A, et al. Treatment planning and delivery of IMRT using 6 and 18MV photon beams without flattening filter. Appl Radiat Isot 2009;67:1629e1637.
  9. Fu W, Dai J, Hu Y, Han D, Song Y. Delivery time comparison for intensity-modulated radiation therapy with/without flattening filter: a planning study. Phys Med Biol 2004;49(8):1535-47. https://doi.org/10.1088/0031-9155/49/8/011
  10. Zhao, B., et al. "SU C BRC 02: Plan Quality and Delivery Efficiency with Varian TrueBeam FFF Mode at High Dose Rate."Medical Physics 38.6 (2011): 3371-3371.