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STUDY ON MONITORING UNIT EFFICIENCY OF FLATTENING-FILTER FREE PHOTON BEAM IN ASSOCIATION WITH TUMOR SIZE AND LOCATION
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 Title & Authors
STUDY ON MONITORING UNIT EFFICIENCY OF FLATTENING-FILTER FREE PHOTON BEAM IN ASSOCIATION WITH TUMOR SIZE AND LOCATION
Kim, Dae Il; Kim, Jung-In; Yoo, Sook Hyun; Park, Jong Min;
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 Abstract
To investigate monitoring unit (MU) efficiency and plan quality of volumetric modulated arc therapy (VMAT) using flattening-filter free (FFF) photon beam in association with target size and location. A virtual patient was generated in Eclipse (ver. A10, Varian Medical Systems, Palo Alto, USA) treatment planning system. The length of major and minor axis in axial view was 50 cm and 30 cm, respectively. Cylindrical-shaped targets were generated inside that patient at the center (symmetric target) and in the periphery (asymmetric target, 7.5 cm away from the center of the patient to the right direction) of the virtual patient. The longitudinal length was 10 cm and the diameters were 2, 5, 10 and 15 cm. Total 8 targets were generated. RapidArc plans using TrueBeam STx were generated for each target. Two full arcs were used and the axis of rotation of the gantry was set to be at the center of the virtual patient. Total MU, homogeneity index (HI), target mean dose, the value of gradient measure and body mean dose were calculated. In the case of symmetric targets, averaged total MU of FFF plan was 23% and 19% higher than that of flattening filter (FF) plan when using 6 MV and 10 MV photons, respectively. The difference of HI, target mean dose, gradient measure and body mean dose between FF and FFF was less than 0.04, 2.6%, 0.1 cm and 2.2%, respectively. For the asymmetric targets, total MU of FFF plan was 21% and 32% was higher than that of FF when using 6 MV and 10 MV photons, respectively. The homogeneity of the target was always worse when using FFF than using FF. The maximum difference of HI was 0.22. The target mean dose of FFF was 3.2% and 4.1% higher than that of FF for the 6 MV and 10 MV, respectively. The difference of gradient measure was less than 0.1 cm. The body mean dose was higher when using FFF than FF about 4.2% and 2.8% for the 6 MV and 10 MV, respectively. No significant differences between VMAT plans of FFF beam and FF beam were observed in terms of quality of treatment plan. The HI was higher when using FFF 10 MV photons for the asymmetric targets. The MU was increased noticeably when using FFF photon beams.
 Keywords
Flattening-filter free photon beam;Monitoring unit efficiency;Volumetric modulated arc therapy;
 Language
English
 Cited by
 References
1.
Otto K. Volumetric modulated arc therapy: IMRT in a single gantry arc. Med. Phys. 2008;35(1):310-317. crossref(new window)

2.
Wolff D, Stieler F, Welzel G, Lorenz F, Abo-Madyan Y, Mai S, Herskind C, Polednik M, Steil V, Wenz F, Lohr F. Volumetric modulated arc therapy (VMAT) vs. serial tomotherapy, step-and-shoot IMRT and 3D-conformal RT for treatment of prostate cancer. Radiotherapy and oncology. 2009;93(2):226-233. crossref(new window)

3.
Alongi F, Cozzi L, Arcangeli S, Iftode C, Comito T, Villa E, Lobefalo F, Navarria P, Reggiori G, Mancosu P, Clerici E, Fogliata A, Tomatis S, Taverna G, Graziotti P, Scorsetti M. Linac based SBRT for prostate cancer in 5 fractions with VMAT and flattening filter free beams: preliminary report of a phase II study. Radiat. Oncol. 2013;8(1):171. crossref(new window)

4.
Ding L, Lo YC, Kadish S, Goff D, Pieters RS, Graeber G, Uy K, Quadri S, Moser R, Martin K, Day J, Fitzgerald TJ. Volume Modulated Arc Therapy (VMAT) for pulmonary Stereotactic Body Radiotherapy (SBRT) in patients with lesions in close approximation to the chest wall. Front Oncol. 2013;3:12.

5.
Titt U, Vassiliev ON, Ponisch F, Dong L, Liu H, Mohan R. A flattening filter free photon treatment concept evaluation with Monte Carlo. Med. Phys. 2006;33(6):1595-1602. crossref(new window)

6.
Mesbahi A, Mehnati P, Keshtkar A, Farajollahi A. Dosimetric properties of a flattening filter-free 6-MV photon beam: a Monte Carlo study. Radiat. Med. 2007;25(7):315-324. crossref(new window)

7.
Benedict SH, Yenice KM, Followill D, Galvin JM, Hinson W, Kavanagh B, Keall P, Lovelock M, Meeks S, Papiez L, Purdie T, Sadagopan R, Schell MC, Salter B, Schlesinger DJ, Shiu AS, Solberg T, Song DY, Stieber V, Timmerman R, Tome W A, Verellen D, Wang L, Yin FF. Stereotactic body radiation therapy: the report of AAPM Task Group 101. Med. Phys. 2010;37(8):4078-4101. crossref(new window)

8.
Wang X, Zhang X, Dong L, Liu H, Gillin M, Ahamad A, Ang K, Mohan R. Effectiveness of noncoplanar IMRT planning using a parallelized multiresolution beam angle optimization method for paranasal sinus carcinoma. Int. J. Radiat. Oncol. Biol. Phys. 2005;63(2):594-601. crossref(new window)

9.
Wagner TH, Bova FJ, Friedman WA, Buatti JM, Bouchet LG, Meeks SL. A simple and reliable index for scoring rival stereotactic radiosurgery plans. Int. J. Radiat. Oncol. Biol. Phys. 2003;57(4):1141-1149. crossref(new window)

10.
Hunt MA, Desobry GE, Fowble B, Coia LR. Effect of low-density lateral interfaces on soft-tissue doses. Int. J. Radiat. Oncol. Biol. Phys. 1997;37(2):475-482. crossref(new window)

11.
Xie J, Cao J, Chen W, Cui Y, Galvin J, Yu Y, Xiao Y. Breast tangential treatment plan using flattening filter-free beams: A planning study. Int. J. Radiat. Oncol. Biol. Phys. 2012;84(3):S867-S867.

12.
Kavanaugh J, R. Kashani, E.E. Klein. Evaluation of flattening filter-free lung/tissue heterogeneity dose calculations for 2 commercial planning systems. Int. J. Radiat. Oncol. Biol. Phys. 2012;84(3):S874-S875.

13.
Vassiliev O, Beddar A, Krishnan S, Briere T, Gillin M, Mohan R and Titt U. A treatment planning study of liver cancer treatments with a flattening filter free linear accelerator. Med. Phys. 2006;33(6):2064-2065.

14.
Kry S, Vassiliev O, Kuban D, Poenisch F, Salehpour M, Gillin M, Mohan R, Titt U. Treatment planning study of prostate cancer IMRT with a flattening filter free accelerator. Med. Phys. 2006;33(6):2146.

15.
Navarria P, Ascolese AM, Mancosu P, Alongi F, Clerici E, Tozzi A, Iftode C, Reggiori G, Tomatis S, Infante M, Alloisio M, Testori A, Fogliata A, Cozzi L, Morenghi E, Scorsetti M. Volumetric modulated arc therapy with flattening filter free (FFF) beams for stereotactic body radiation therapy (SBRT) in patients with medically inoperable early stage non small cell lung cancer (NSCLC). Radiother. Oncol. 2013;107(3):414-418. crossref(new window)

16.
Scorsetti M, Alongi F, Castiglioni S, Clivio A, Fogliata A, Lobefalo F, Mancosu P, Navarria P, Palumbo V, Pellegrini C, Pentimalli S, Reggiori G, Ascolese AM, Roggio A, Arcangeli S, Tozzi A, Vanetti E, Cozzi L. Feasibility and early clinical assessment of flattening filter free (FFF) based stereotactic body radiotherapy (SBRT) treatments. Radiat. Oncol. 2011;6:113. crossref(new window)