ESTRO 2024 - Abstract Book

S1455

Clinical - Head & neck

ESTRO 2024

The risk of spatial or structural changes in patients with HNC during the course of radiotherapy is very high. They are most common in the fourth or fifth week of therapy.

The multidisciplinary evaluation of CBCT images allows for the early detection of clinically significant differences in volume and the localisation of the target volumes and the OARs. The AAR procedure allows to maintenance of dose coverage of the targeted volumes, ensures proper dose homogeneity as well and to reduce the potential intensification of normal tissue toxicity. Correction of unintended changes may lead to an improvement in the outcome and toxicity profile. The proposed scheme could be relatively easily implemented in centres that do not have dedicated patient replanning software. The real impact of AAR on treatment outcomes and radiation toxicity is a matter for further investigation.

Keywords: Adaptive radiotherapy, head and neck cancer, IMRT.

References:

Morgan HE, Sher DJ. Adaptive radiotherapy for head and neck cancer. Cancers Head Neck. 2020 Jan 9;5:1. doi: 10.1186/s41199-019-0046-z. PMID: 31938572; PMCID: PMC6953291.

Castelli J, Simon A, Louvel G, Henry O, Chajon E, Nassef M, Haigron P, Cazoulat G, Ospina JD, Jegoux F, Benezery K, de Crevoisier R. Impact of head and neck cancer adaptive radiotherapy to spare the parotid glands and decrease the risk of xerostomia. Radiat Oncol. 2015 Jan 9;10:6. doi: 10.1186/s13014-014-0318-z. PMID: 25573091; PMCID: PMC4311461.

3382

Proffered Paper

Safety and clinical benefit of reduced elective dose in head & neck cancer: results of a randomized controlled trial (NCT02442375)

S. van den Bosch 1 , P.A.H. Doornaert 2 , F.J.P. Hoebers 3 , B. Kreike 4 , M.R. Vergeer 5 , T. Dijkema 1 , E.M. Zwijnenburg 1 , G. Hannink 6 , J.H.A.M. Kaanders 1 1 Radboudumc, Department of Radiation Oncology, Nijmegen, Netherlands. 2 University Medical Center Utrecht, Department of Radiation Oncology, Utrecht, Netherlands. 3 Maastricht University, Department of Radiation Oncology (MAASTRO), Maastricht, Netherlands. 4 Radiotherapiegroep, Department of Radiation Oncology, Arnhem, Netherlands. 5 Amsterdam UMC, Department of Radiation Oncology, Amsterdam, Netherlands. 6 Radboudumc, Institute for Health Sciences, Nijmegen, Netherlands

Purpose/Objective: