ESTRO 2024 - Abstract Book

S1856

Clinical - Mixed sites, palliation

ESTRO 2024

Figure 2: Qualitive treatment quality within dose plannings techniques with a different MDT.

The planning technique with an MDT of 100 seconds was deemed as the optimal planning technique, based on the results and assessment by the radiation oncologist. A substantial and significant (p = 0.002) average reduction in true delivery time of about 40% was found when comparing the optimal planning technique to the clinically used treatment planning technique. On average, the delivery of an optimal plan and clinically used treatment plan took 133 and 225 seconds, respectively. All optimal treatment plans passed PSQA-checks with equal or better gamma pass-rates compared to clinically used treatment plans.

Conclusion:

A substantial (40%) reduction in true delivery time can be achieved whilst maintaining qualitative and quantitative treatment plan quality. The use of a maximum delivery time of 100 seconds is recommended for patients receiving one or two treatment fractions on spinal metastases.

Keywords: Palliative care, spinal metastases, VMAT

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Eligibility for MR-HIFU in patients with non-spinal bone metastases referred for radiotherapy

Renée Hovenier 1 , Derk J. Slotman 1,2 , Chiara Gasperini 3 , Alice Zamagni 4,5 , Mira Huhtala 6 , Lambertus W. Bartels 1 , Manon N.G.J.A. Braat 1 , Wietse S.C. Eppinga 1 , Nicolien Kasperts 1 , Erik C.J. Phernambucq 7 , Martijn F. Boomsma 1,2 , Ingrid M. Nijholt 2 , Roberto Blanco Sequieros 8 , Alberto Bazzocchi 3 , Alessio G. Morganti 4,5 , Chrit T.W. Moonen 1 , Clemens Bos 1 , Helena M. Verkooijen 1 1 University Medical Center Utrecht, Division Imaging and Oncology, Utrecht, Netherlands. 2 Isala Hospital, Department of Radiology, Zwolle, Netherlands. 3 IRCCS Istituto Ortopedico Rizzoli, Diagnostic and Interventional