56th SSRMP Annual Meeting

Session

Session II

30 Nov 2023, 13:10

Konferenzsaal Coronado (Conference Center)

25. Modelling the biological effect of temporally feathered radiotherapy

Daniel Hosie (ETH Zurich)

30/11/2023, 13:10

Radiation Therapy

Oral

Purpose: Temporally feathered radiotherapy (TFRT) replaces a standard treatment plan by 5 iso-curative sub-plans (López Alfonso et al. Med Phys 2018). Each sub-plan is created such that one of five chosen organs-at-risk (OARs) receives a higher dose compared to the standard plan in one fraction, allowing the other four OARs to receive a lower dose. Each OAR then receives one high and four low...

33. RT-EQD2: a tool for 3D evaluation of biologically weighted dose estimates

Lukas Wissmann (Institute for Radiation Oncology, Spital Thurgau AG, Münsterlingen, Switzerland)

30/11/2023, 13:20

Radiation Therapy

Oral

Purpose:
Accurate and realistic dose accumulation in external beam radiotherapy planning becomes increasingly important in the context of repeat irradiations to returning patients. Rather than straight sums of physical dose, radiotherapy professionals prefer biologically weighted dose estimates to support prescription of repeat irradiations. This work presents a framework for creating...

2. Revolutionizing particle therapy: a compact and cost-effective cyclotron-based proton facility

Vivek Maradia (PSI - Paul Scherrer Institut)

30/11/2023, 13:30

Radiation Therapy

Oral

Purpose:
Particle therapy has shown clinical advantages over conventional radiation therapy, particularly for head and neck cancer and pediatric brain cancer treatment. However, limited availability is mainly due to high costs and facility size. Our goal is to design a more compact and cost-effective multi-room particle therapy facility using a cyclotron-based proton therapy...

31. First in-beam measurements of a multi-field proton treatment plan with the open-ring PETITION scanner

Keegan McNamara (PSI - Paul Scherrer Institut)

30/11/2023, 13:40

Radiation Therapy

Oral

Purpose
In-vivo range verification of proton therapy with PET provides a unique opportunity for 3D verification of treatment fields delivered to patients. In-beam and inter-field imaging is possible with use of an open-ring design, allowing uninterrupted delivery of treatment fields. We present the first proof of concept measurements for full in-beam and inter-field imaging using the recently...

32. A comprehensive analysis of RBE uncertainties and their potential clinical consequences for head and neck cancer

Lisa Stefanie Fankhauser (PSI - Paul Scherrer Institut)

30/11/2023, 13:50

Radiation Therapy

Oral

Purpose
To evaluate the robustness of proton treatment plans to relative biological effectiveness (RBE) uncertainties based on target coverage and tissue toxicity using a normal tissue complication probability (NTCP) model.
Methods
Two different clinically used treatment planning techniques, a four-field and a six-field technique, combined with two optimization methods, planning target...

34. Comprehensive exploration of beam size and divergence variations in proton therapy facilities

Isabella Colizzi (PSI - Paul Scherrer Institut)

30/11/2023, 14:00

Radiation Therapy

Oral

Purpose
For a cyclotron-based facility, one of the methods for improving beam transmission is to transport higher emittance through the beamline, which can lead to larger beam sizes and/or divergence with respect to the ideal treatment planning requirements. A similar problem exists in multi-room facilities, where small differences between the transport beam lines for each treatment room...

22. Direct aperture optimization-based pathfinding for non-isocentric dynamic trajectory radiotherapy applied to a craniospinal irradiation case

Gian Guyer (Division of Medical Radiation Physics and Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern, Bern, Switzerland)

30/11/2023, 14:10

Radiation Therapy

Oral

Purpose: Non-isocentric dynamic trajectory radiotherapy (DTRT) is enabled through dynamic table translations in synchrony with intensity modulation and dynamic gantry, table and/or collimator rotation. Non-isocentric DTRT was shown to improve delivery time for craniospinal irradiation (CSI) compared to multi-isocentric intensity modulated radiotherapy (IMRT) by moving the table longitudinally...

24. Comparison of geometric and dosimetric-based path-finding for dynamic collimator-radiotherapy (colli-DTRT)

Annalisa Walpen (Division of Medical Radiation Physics and Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern, Bern, Switzerland)

30/11/2023, 14:20

Radiation Therapy

Oral

Purpose: Dynamic-collimator trajectory radiotherapy (colli-DTRT) delivers intensity modulated radiotherapy with non-coplanar partial arcs and dynamic-collimator rotation. We compare two path-finding approaches for colli-DTRT, geometric and dosimetric, investigating the impact of organ-at-risk (OAR) prioritization on the path-finding and dosimetric plan quality.

Methods: In the...

30. Robust dynamic-collimator trajectory radiotherapy (colli-DTRT)

Alina Paunoiu (Division of Medical Radiation Physics and Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern, Bern, Switzerland, and Department of Biomedical Engineering, ETH Zürich, Zürich, Switzerland)

30/11/2023, 14:30

Radiation Therapy

Oral

Purpose: To develop robust dynamic-collimator trajectory radiotherapy (colli-DTRT), including robust dosimetrically motivated path-finding, to manage patient set-up uncertainties.
Methods: colli-DTRT plans were created for one brain (30 x 2 Gy) and one breast (16 x 2.65 Gy) clinically motivated cases. colli-DTRT paths were generated through iterative fluence map optimization (FMO) and beam...