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The impact of reference isocentre position on set-up errors in head-and-neck image-guided radiotherapy

Published online by Cambridge University Press:  02 October 2017

Helena Lenko  and
Primož Peterlin
Helena Lenko
Affiliation:
Institute of Oncology Ljubljana, Ljubljana, Slovenia
Primož Peterlin*
Affiliation:
Institute of Oncology Ljubljana, Ljubljana, Slovenia
*
Correspondence to: Primož Peterlin, Institute of Oncology Ljubljana, Zaloška c. 2, SI-1000 Ljubljana, Slovenia. Tel: +386 1 5879509. E-mail: [email protected]
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Abstract

Aim

To examine and quantify set-up errors in patient positioning in head-and-neck radiotherapy and to investigate the impact of the choice of reference isocentre—on the patient neck or patient skull—on the magnitude of set-up errors.

Materials and methods

Set-up position corrections obtained using online kV 2D/2D matching were recorded automatically for every treatment fraction. 3,413 treatment records for 117 patients treated with volumetric modulated arc therapy during 2013 and 2014 on a single treatment machine in our clinic were analysed. In 79 treatment plans the reference isocentre was set to the patient skull, and in 47 to the neck.

Results

Standard deviation of group systematic error in the vertical, longitudinal and lateral direction and the couch rotation were found to be 2·5 mm, 2·1 mm, 1·9 mm and 0·43° (skull) and 2·5 mm, 1·8 mm, 1·7 mm and 0·49° (neck), respectively. Random error of the vertical, longitudinal, lateral and rotational position correction was 1·8 mm, 1·5 mm, 1·6 mm and 0·62° (skull) and 1·9 mm, 1·6 mm, 1·5 mm and 0·60° (neck), respectively. Positional shifts in different directions were found to be uncorrelated.

Conclusions

Neither reference isocentre set-up shows a clear advantage over the other in terms of interfraction set-up error.

Keywords

head-and-neck radiotherapypatient originreference isocentreset-up error
Type
Original Articles
Information
Journal of Radiotherapy in Practice , Volume 17 , Issue 1 , March 2018 , pp. 104 - 113
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Copyright
© Cambridge University Press 2017 

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References

1. Aird, E, Conway, J. CT simulation for radiotherapy treatment planning. Br J Radiol 2002; 75 (900): 937–949.CrossRefGoogle ScholarPubMed
2. R Core Team. R: A Language and Environment for Statistical Computing. Vienna, Austria: R Foundation for Statistical Computing, 2014.Google Scholar
3. van Herk, M. Errors and margins in radiotherapy. Semin Radiat Oncol 2004; 14 (1): 52–64.CrossRefGoogle ScholarPubMed
4. Remeijer, P, Geerlof, E, Ploeger, L et al. 3-D portal image analysis in clinical practice: an evaluation of 2-D and 3-D analysis techniques as applied to 30 prostate cancer patients. Int J Radiat Oncol Biol Phys 2000; 46 (5): 1281–1290.CrossRefGoogle ScholarPubMed
5. de Boer, H C, van Sörnsen de Koste, J R, Creutzberg, C L, Visser, A G, Levendag, P C, Heijmen, B J. Electronic portal image assisted reduction of systematic set-up errors in head and neck irradiation. Radioth Oncol 2001; 61 (3): 299–308.CrossRefGoogle ScholarPubMed
6. Bel, A, van Herk, M, Bartelink, H, Lebesque, J V. A verification procedure to improve patient set-up accuracy using portal images. Radioth Oncol 1993; 29 (2): 253–260.CrossRefGoogle ScholarPubMed
7. Gilbeau, L, Octave-Prignot, M, Loncol, T, Renard, L, Scalliet, P, Grégoire, V. Comparison of setup accuracy of three different thermoplastic masks for the treatment of brain and head and neck tumors, Radioth. Oncol 2001; 58 (2): 155–162.Google Scholar
8. van Lin, E N J T, van der Vight, L, Huizenga, H, Kaanders, J H A M, Visser, A G. Set-up improvement in head and neck radiotherapy using a 3D off-line EPID-based correction protocol and a customised head and neck support. Radioth Oncol 2003; 68 (2): 137–148.CrossRefGoogle Scholar
9. Suzuki, M, Nishimura, Y, Nakamatsu, K et al. Analysis of interfractional set-up errors and intrafractional organ motions during IMRT for head and neck tumors to define an appropriate planning target volume (PTV)-and planning organs at risk volume (PRV)-margins. Radioth Oncol 2006; 78 (3): 283–290.CrossRefGoogle ScholarPubMed
10. Gupta, T, Chopra, S, Kadam, A et al. Assessment of three-dimensional set-up errors in conventional head and neck radiotherapy using electronic portal imaging device. Radiat Oncol 2007; 2: 44.CrossRefGoogle ScholarPubMed
11. Strbac, B, Jokic Spasic, V. Evaluation of set-up errors in head and neck radiotherapy using electronic portal imaging. Phys Medica 2013; 29 (5): 531–536.CrossRefGoogle ScholarPubMed
12. Zumsteg, Z, DeMarco, J, Lee, S P et al. Image guidance during head-and-neck cancer radiation therapy: analysis of alignment trends with in-room cone-beam computed tomography scans. Int J Radiat Oncol Biol Phys 2012; 83 (2): 712–719.CrossRefGoogle ScholarPubMed
13. Oh, Y K, Baek, J, Kim, O B, Kim, J H. Assessment of setup uncertainties for various tumor sites when using daily CBCT for more than 2200 VMAT treatments. J Appl Clin Med Phys 2014; 15 (2): 85–99.CrossRefGoogle ScholarPubMed
14. Kapanen, M, Laaksomaa, M, Tulijoki, T, Kellokumpu-Lehtinen, P L, Hyödynmaa, S. Effects of remedies made in patient setup process on residual setup errors and margins in head and neck cancer radiotherapy based on 2D image guidance. Rep Pract Oncol Radioth 2015; 20 (4): 292–298.CrossRefGoogle ScholarPubMed
15. van Kranen, S, van Beek, S, Rasch, C, van Herk, M, Sonke, J J. Setup uncertainties of anatomical sub-regions in head-and-neck cancer patients after offline CBCT guidance. Int J Radiat Oncol Biol Phys 2009; 73 (5): 1566–1573.CrossRefGoogle ScholarPubMed
16. Ciardo, D, Alterio, D, Jereczek-Fossa, B A et al. Set-up errors in head and neck cancer patients treated with intensity modulated radiation therapy: quantitative comparison between three-dimensional cone-beam CT and two-dimensional kilovoltage images. Phys Medica 2015; 31 (8): 1015–1021.CrossRefGoogle ScholarPubMed
17. Nyarambi, I, Chamunyonga, C, Pearce, A. CBCT image guidance in head and neck irradiation: the impact of daily and weekly imaging protocols. J Radioth Pract 2015; 14: 362–369.CrossRefGoogle Scholar
18. Waldon, A, Plank, A, Middleton, M. Analysis of online and offline head and neck image-guided radiation therapy. J Med Imag Rad Sci 2014; 45 (2): 79–84.CrossRefGoogle ScholarPubMed
19. Bland, J M, Altman, D. Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1986; 327 (8476): 307–310.CrossRefGoogle Scholar
20. Kragelj, B. Setup error and its effect on safety margin in conformal radiotherapy of the prostate. Radiol Oncol 2005; 39 (3): 211–217.Google Scholar
21. Yan, G, Mittauer, K, Huang, Y, Lu, B, Liu, C, Li, J G. Prevention of gross setup errors in radiotherapy with an efficient automatic patient safety system. J Appl Clin Med Phys 2013; 14 (6): 322–337.CrossRefGoogle ScholarPubMed
22. Verellen, D, Ridder, M D, Linthout, N, Tournel, K, Soete, G, Storme, G. Innovations in image-guided radiotherapy. Nat Rev Cancer 2007; 7 (12): 949–960.CrossRefGoogle ScholarPubMed
23. Devereux, B, Frantzis, J, Sisson, T, Jones, M, Martin, J, Middleton, M. A comparison of kV and MV imaging in head and neck image guided radiotherapy. Radiography 2010; 16 (1): 8–13.CrossRefGoogle Scholar
24. Walter, C, Boda-Heggemann, J, Wertz, H et al. Phantom and in-vivo measurements of dose exposure by image-guided radiotherapy (IGRT): MV portal images vs. kV portal images vs. cone-beam CT. Radioth Oncol 2007; 85 (3): 418–423.CrossRefGoogle ScholarPubMed
25. Swiss Society of Radiobiology and Medical Physics. Quality assurance of gantry-mounted image-guided radiotherapy systems, Tech. Rep. Recommendations No. 16. (Sep. 2010). http://ssrpm.ch/wp-content/uploads/2014/08/r16igr-e.pdf. Accessed 24th July 2017.Google Scholar