Abstract
When planning breast IMRT, the distance of the CTV from the patient external surface is often less than the PTV margin required, presenting difficulties for ensuring CTV coverage. Several techniques have been proposed to ensure coverage in this scenario, one of which is robust optimisation; a technique that simultaneously optimises a plan in multiple geometries representing the worst case setup error expected. A range of plans were created utilising opposed tangential beams and these differing planning techniques, and were delivered and computed at 5 and 10 mm offsets perpendicular to the beam axes. The accuracy of dose computation was verified with a scintillator and film, and the surface dose coverage was evaluated for each of the plans in the offset positions. When 10 mm robust optimisation was used the CTV minimum, maximum and mean dose at the 5 and 10 mm offset locations were all within 3 % of those at the no offset setup. Robust optimisation was found to be comparable to other established planning methods for ensuring coverage of the breast CTV with setup variations.
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References
Lin Y, Wang B (2015) Dosimetric absorption of intensity-modulated radiotherapy compared with conventional radiotherapy in breast-conserving surgery. Oncol Lett 9:9–14. doi:10.3892/ol.2014.2704
Dogan N, Cuttino L, Lloyd R et al (2007) Optimized dose coverage of regional lymph nodes in breast cancer: the role of intensity-modulated radiotherapy. Int J Radiat Oncol Biol Phys 68:1238–1250. doi:10.1016/j.ijrobp.2007.03.059
Donovan E, Bleakley N, Denholm E et al (2007) Randomised trial of standard 2D radiotherapy (RT) versus intensity modulated radiotherapy (IMRT) in patients prescribed breast radiotherapy. Radiother Oncol 82:254–264. doi:10.1016/j.radonc.2006.12.008
Pignol J-P, Olivotto I, Rakovitch E et al (2008) A multicenter randomized trial of breast intensity-modulated radiation therapy to reduce acute radiation dermatitis. J Clin Oncol 26:2085–2092. doi:10.1200/JCO.2007.15.2488
Thomas SJ, Hoole ACF (2004) The effect of optimization on surface dose in intensity modulated radiotherapy (IMRT). Phys Med Biol 49:4919–4928
Neve WD, Wu Y, Ezzell G (2006) Practical IMRT planning. In: Bortfeld T, Schmidt-Ullrich R, Neve WD, Wazer DE (eds) Image-guided IMRT. Springer, Berlin, pp 47–59
Thilmann C, Grosser KH, Rhein B et al (2002) Virtual bolus for inversion radiotherapy planning in intensity-modulated radiotherapy of breast carcinoma within the scope of adjuvant therapy. Strahlenther Onkol 178:139–146
Bortfeld T, Chan TCY, Trofimov A, Tsitsiklis JN (2008) Robust management of motion uncertainty in intensity-modulated radiation therapy. Oper Res 56:1461–1473. doi:10.1287/opre.1070.0484
Chan TCY, Bortfeld T, Tsitsiklis JN (2006) A robust approach to IMRT optimization. Phys Med Biol 51:2567–2583. doi:10.1088/0031-9155/51/10/014
Fredriksson A, Forsgren A, Hårdemark B (2015) Maximizing the probability of satisfying the clinical goals in radiation therapy treatment planning under setup uncertainty. Med Phys 42:3992–3999. doi:10.1118/1.4921998
Chu M, Zinchenko Y, Henderson SG, Sharpe MB (2005) Robust optimization for intensity modulated radiation therapy treatment planning under uncertainty. Phys Med Biol 50:5463. doi:10.1088/0031-9155/50/23/003
Fredriksson A (2012) A characterization of robust radiation therapy treatment planning methods-from expected value to worst case optimization. Med Phys 39:5169–5181. doi:10.1118/1.4737113
Nguyen TB, Hoole ACF, Burnet NG, Thomas SJ (2009) The optimization of intensity modulated radiotherapy in cases where the planning target volume extends into the build-up region. Phys Med Biol 54:2511. doi:10.1088/0031-9155/54/8/017
Jones S, Fitzgerald R, Owen R, Ramsay J (2015) Quantifying intra- and inter-fractional motion in breast radiotherapy. J Med Radiat Sci 62:40–46. doi:10.1002/jmrs.61
George R, Keall PJ, Kini VR et al (2003) Quantifying the effect of intrafraction motion during breast IMRT planning and dose delivery. Med Phys 30:552–562. doi:10.1118/1.1543151
Fredriksson A, Forsgren A, Hårdemark B (2011) Minimax optimization for handling range and setup uncertainties in proton therapy. Med Phys 38:1672–1684. doi:10.1118/1.3556559
(2014) RayStation 4.5 User Manual. RaySearch Laboratories AB, Stockholm, Sweden
Zhang G, Jiang Z, Shepard D et al (2006) Direct aperture optimization of breast IMRT and the dosimetric impact of respiration motion. Phys Med Biol 51:N357–N369. doi:10.1088/0031-9155/51/20/N01
Ashburner MJ, Tudor S (2014) The optimization of superficial planning target volumes (PTVs) with helical tomotherapy. J Appl Clin Med Phys 15:4560
Carrasco P, Jornet N, Jordi O et al (2015) Characterization of the Exradin W1 scintillator for use in radiotherapy. Med Phys 42:297–304. doi:10.1118/1.4903757
Beaulieu L, Goulet M, Archambault L, Beddar S (2013) Current status of scintillation dosimetry for megavoltage beams. J Phys Conf Ser 444:12013. doi:10.1088/1742-6596/444/1/012013
Mijnheer B, Beddar S, Izewska J, Reft C (2013) In vivo dosimetry in external beam radiotherapy. Med Phys 40:70903. doi:10.1118/1.4811216
Ferreira BC, Lopes MC, Capela M (2009) Evaluation of an Epson flatbed scanner to read Gafchromic EBT films for radiation dosimetry. Phys Med Biol 54:1073–1085. doi:10.1088/0031-9155/54/4/017
Fiandra C, Ricardi U, Ragona R et al (2006) Clinical use of EBT model Gafchromic film in radiotherapy. Med Phys 33:4314–4319. doi:10.1118/1.2362876
Shima K, Tateoka K, Saitoh Y et al (2012) Analysis of post-exposure density growth in radiochromic film with respect to the radiation dose. J Radiat Res 53:301–305
Butson MJ, Cheung T, Yu PKN (2006) Scanning orientation effects on Gafchromic EBT film dosimetry. Australas Phys Eng Sci Med 29:281–284
Moylan R, Aland T, Kairn T (2013) Dosimetric accuracy of Gafchromic EBT2 and EBT3 film for in vivo dosimetry. Australas Phys Eng Sci Med 36:331–337. doi:10.1007/s13246-013-0206-0
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Byrne, M., Hu, Y. & Archibald-Heeren, B. Evaluation of RayStation robust optimisation for superficial target coverage with setup variation in breast IMRT. Australas Phys Eng Sci Med 39, 705–716 (2016). https://doi.org/10.1007/s13246-016-0466-6
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DOI: https://doi.org/10.1007/s13246-016-0466-6