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Strahlentherapie und Onkologie

, Volume 194, Issue 7, pp 664–674 | Cite as

Shorter treatment times reduce the impact of intra-fractional motion

A real-time 4DUS study comparing VMAT vs. step-and-shoot IMRT for prostate cancer
  • Hendrik BallhausenEmail author
  • Minglun Li
  • Ute Ganswindt
  • Claus Belka
Original Article

Abstract

Purpose

To evaluate the impact of shorter treatment times on intra-fractional motion of the prostate during external beam radiotherapy.

Methods

53 h of intra-fractional motion of the prostate were recorded in real-time by 4D ultrasound (4DUS) during 720 fractions in 28 patients, 14 of which whom treated with step-and-shoot intensity-modulated radiotherapy (IMRT) and 14 of whom were treated with volumetric arc therapy (VMAT).

Results

The average VMAT fraction was recorded for 2 min 43 s and was substantially shorter than the average step-and-shoot IMRT fraction at 6 min 13 s. Average radial displacement of the prostate per fraction was substantially and significantly reduced from 1.31 ± 1.28 mm (n = 357 step-and-shoot IMRT fractions) to 0.96 ± 1.04 mm (n = 363 VMAT fractions), p = 0.00004. Radial, vertical, and longitudinal root-mean-square (r. m. s.) error per fraction was reduced from 1.55 to 1.12 mm (−28%, p < 0.0001), from 1.16 to 0.77 mm (−34%, p < 0.0001), and from 0.79 to 0.56 mm (−29%, p = 0.0002), respectively. Lateral intra-fractional motion was generally small and did not differ significantly. The prostate remained during 95% of fraction time within 4.55 mm of the isocenter in case of step-and-shoot IMRT and within 2.45 mm in case of VMAT. The variance of displacements increased linearly with time, and the rate was the same for both step-and-shoot IMRT and VMAT patients.

Conclusions

The position of the prostate changed less during shorter fractions, limiting fraction-average and end-of-fraction variance. This substantially and significantly reduced the impact of intra-fractional motion during shorter VMAT fractions as compared to longer step-and-shoot IMRT fractions.

Keywords

Organ motion Ultrasound imaging Volumetric-modulated arc therapy Radiotherapy, intensity-modulated Prostate cancer 

Kürzere Behandlungszeit reduziert den Einfluss intrafraktioneller Bewegung

Eine Echtzeit-4DUS-Studie vergleicht VMAT vs. Step-and-shoot-IMRT beim Prostatakarzinom

Zusammenfassung

Zielsetzung

Die Studie untersucht den Einfluss kürzerer Behandlungszeiten auf das Ausmaß der intrafraktionellen Bewegung der Prostata während einer Strahlentherapie.

Methoden

In Echtzeit wurden 53 h intrafraktioneller Bewegung der Prostata mit vierdimensionalem Ultraschall (4DUS) während 720 Fraktionen in 28 Patienten aufgezeichnet. Davon wurden 14 Patienten mit intensitätsmodulierter Strahlentherapie (IMRT) im Step-and-shoot-Verfahren behandelt und 14 Patienten im Volumetric-Arc-Therapy-Protokoll (VMAT).

Ergebnisse

Die mittlere VMAT-Fraktion wurde für 2 min und 43 s aufgezeichnet und war damit deutlich kürzer als die mittlere Step-and-shoot-IMRT-Fraktion mit 6 min und 13 s. Die mittlere radiale Auslenkung der Prostata pro Fraktion wurde deutlich und signifikant reduziert von 1,31 ± 1,28 mm (357 Step-and-shoot-IMRT-Fraktionen) auf 0,96 ± 1,04 mm (363 VMAT-Fraktionen; p = 0,00004). Radiale, vertikale und longitudinale Root-Mean-Square-Fehler (r. m. s.) pro Fraktion wurden reduziert von 1,55 auf 1,12 mm (−28 %; p < 0,0001) bzw. von 1,16 auf 0,77 mm (−34 %; p < 0,0001) bzw. von 0,79 auf 0,56 mm (−29 %; p = 0,0002). Die laterale intrafraktionelle Bewegung war allgemein klein und unterschied sich nicht signifikant. Die Prostata blieb während der Dauer einer Fraktion zu 95 % innerhalb von 4,55 mm im Falle von Step-and-shoot-IMRT und innerhalb von 2,45 mm im Falle von VMAT. Die Varianz der Verschiebungen nahm linear mit der Behandlungszeit zu, wobei die Steigung bei beiden Protokollen die gleiche war.

Schlussfolgerung

Die Prostataposition verändert sich während kürzerer Fraktionen weniger, was die mittlere Varianz und die Varianz am Ende der Fraktion begrenzt. Dies reduziert deutlich und signifikant den Einfluss der intrafraktionellen Bewegung während kürzerer VMAT-Fraktionen im Vergleich zu längeren Step-and-shoot-IMRT-Fraktionen.

Schlüsselwörter

Organbewegung Ultraschall Volumetrisch modulierte Arc-Therapie Strahlentherapie, intensitätsmodulierte Prostatakarzinom 

Notes

Compliance with ethical guidelines

Conflict of interest

U. Ganswindt and C. Belka have a research cooperation with Elekta AB, Stockholm, Sweden. H. Ballhausen and M. Li declare that they have no competing interests.

Ethical standards

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. For this type of study formal consent is not required. This article does not contain any studies with animals performed by any of the authors.

References

  1. 1.
    Krengli M, Loi G, Pisani C, Beldi D, Apicella G, Amisano V et al (2016) Three-dimensional surface and ultrasound imaging for daily IGRT of prostate cancer. Radiat Oncol 11:159CrossRefGoogle Scholar
  2. 2.
    Bell K, Heitfeld M, Licht N, Rube C, Dzierma Y (2017) Influence of daily imaging on plan quality and normal tissue toxicity for prostate cancer radiotherapy. Radiat Oncol 12:7CrossRefGoogle Scholar
  3. 3.
    Park SS, Yan D, McGrath S, Dilworth JT, Liang J, Ye H et al (2012) Adaptive image-guided radiotherapy (IGRT) eliminates the risk of biochemical failure caused by the bias of rectal distension in prostate cancer treatment planning: clinical evidence. Int J Radiat Oncol Biol Phys 83:947–952CrossRefGoogle Scholar
  4. 4.
    Jolnerovski M, Salleron J, Beckendorf V, Peiffert D, Baumann AS, Bernier V et al (2017) Intensity-modulated radiation therapy from 70 Gy to 80 Gy in prostate cancer: six-year outcomes and predictors of late toxicity. Radiat Oncol 12:99CrossRefGoogle Scholar
  5. 5.
    Robinson D, Liu D, Steciw S, Field C, Daly H, Saibishkumar EP et al (2012) An evaluation of the Clarity 3D ultrasound system for prostate localization. J Appl Clin Med Phys 13:3753CrossRefGoogle Scholar
  6. 6.
    Baker M, Behrens CF (2016) Determining intrafractional prostate motion using four dimensional ultrasound system. BMC Cancer 16:484CrossRefGoogle Scholar
  7. 7.
    Beltran C, Herman MG, Davis BJ (2008) Planning target margin calculations for prostate radiotherapy based on intrafraction and interfraction motion using four localization methods. Int J Radiat Oncol Biol Phys 70:289–295CrossRefGoogle Scholar
  8. 8.
    Huang E, Dong L, Chandra A, Kuban DA, Rosen II, Evans A et al (2002) Intrafraction prostate motion during IMRT for prostate cancer. Int J Radiat Oncol Biol Phys 53:261–268CrossRefGoogle Scholar
  9. 9.
    Oehler C, Lang S, Dimmerling P, Bolesch C, Kloeck S, Tini A et al (2014) PTV margin definition in hypofractionated IGRT of localized prostate cancer using cone beam CT and orthogonal image pairs with fiducial markers. Radiat Oncol 9:229CrossRefGoogle Scholar
  10. 10.
    Quan EM, Li X, Li Y, Wang X, Kudchadker RJ, Johnson JL et al (2012) A comprehensive comparison of IMRT and VMAT plan quality for prostate cancer treatment. Int J Radiat Oncol Biol Phys 83:1169–1178CrossRefGoogle Scholar
  11. 11.
    Wolff D, Stieler F, Welzel G, Lorenz F, Abo-Madyan Y, Mai S et al (2009) Volumetric modulated arc therapy (VMAT) vs. serial tomotherapy, step-and-shoot IMRT and 3D-conformal RT for treatment of prostate cancer. Radiother Oncol 93:226–233CrossRefGoogle Scholar
  12. 12.
    Teoh M, Clark CH, Wood K, Whitaker S, Nisbet A (2011) Volumetric modulated arc therapy: a review of current literature and clinical use in practice. Br J Radiol 84:967–996CrossRefGoogle Scholar
  13. 13.
    Hoogeman MS, Nuyttens JJ, Levendag PC, Heijmen BJ (2008) Time dependence of intrafraction patient motion assessed by repeat stereoscopic imaging. Int J Radiat Oncol Biol Phys 70:609–618CrossRefGoogle Scholar
  14. 14.
    Rossi MM, Peulen HM, Belderbos JS, Sonke JJ (2016) Intrafraction motion in stereotactic body radiation therapy for non-small cell lung cancer: intensity modulated radiation therapy versus volumetric modulated arc therapy. Int J Radiat Oncol Biol Phys 95:835–843CrossRefGoogle Scholar
  15. 15.
    Ipsen S, Bruder R, O’Brien R, Keall PJ, Schweikard A, Poulsen PR (2016) Online 4D ultrasound guidance for real-time motion compensation by MLC tracking. Med Phys 43:5695CrossRefGoogle Scholar
  16. 16.
    Lachaine M, Falco T (2013) Intrafractional prostate motion management with the Clarity autoscan system. Med Phys Int 1:72–80Google Scholar
  17. 17.
    Li M, Hegemann NS, Manapov F, Kolberg A, Thum PD, Ganswindt U et al (2017) Prefraction displacement and intrafraction drift of the prostate due to perineal ultrasound probe pressure. Strahlenther Onkol 193:459–465CrossRefGoogle Scholar
  18. 18.
    Ballhausen H, Hieber S, Li M, Belka C, Reiner M (2014) Millimeter precision in ultrasound based patient positioning: experimental quantification of inherent technical limitations. Med Phys 41:81718CrossRefGoogle Scholar
  19. 19.
    Ballhausen H, Reiner M, Kantz S, Belka C, Sohn M (2013) The random walk model of intrafraction movement. Phys Med Biol 58:2413–2427CrossRefGoogle Scholar
  20. 20.
    Ballhausen H, Li M, Hegemann NS, Ganswindt U, Belka C (2015) Intra-fraction motion of the prostate is a random walk. Phys Med Biol 60:549–563CrossRefGoogle Scholar
  21. 21.
    Pommer T, Hun Oh J, Munck af Rosenschöld P, Deasy OJ (2017) Simulating intrafraction prostate motion with a random walk model. Adv Radiat Oncol 2(3):429–436.  https://doi.org/10.1016/j.adro.2017.03.005 CrossRefPubMedPubMedCentralGoogle Scholar
  22. 22.
    Kotte AN, Hofman P, Lagendijk JJ, van Vulpen M, van der Heide UA (2007) Intrafraction motion of the prostate during external-beam radiation therapy: analysis of 427 patients with implanted fiducial markers. Int J Radiat Oncol Biol Phys 69:419–425CrossRefGoogle Scholar
  23. 23.
    Juneja P, Colvill E, Kneebone A, Eade T, Ng JA, Thwaites DI et al (2017) Quantification of intrafraction prostate motion and its dosimetric effect on VMAT. Australas Phys Eng Sci Med 40:317–324CrossRefGoogle Scholar
  24. 24.
    Legge K, Nguyen D, Ng JA, Wilton L, Richardson M, Booth J et al (2017) Real-time intrafraction prostate motion during linac based stereotactic radiotherapy with rectal displacement. J Appl Clin Med Phys 18:130–136CrossRefGoogle Scholar
  25. 25.
    Xie Y, Djajaputra D, King CR, Hossain S, Ma L, Xing L (2008) Intrafractional motion of the prostate during hypofractionated radiotherapy. Int J Radiat Oncol Biol Phys 72:236–246CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Radiation Oncology, University HospitalLMU MunichMunichGermany

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