Commissioning and clinical implementation of an independent dose calculation system for scanned proton beams.

Purpose: Experimental patient-specific QA (PSQA) is a time and resource-intensive process, with a poor sensitivity in detecting errors. Radiation therapy facilities aim to substitute it by means of independent dose calculation (IDC) in combination with a comprehensive beam delivery QA program. This paper reports on the commissioning of the IDC software tool myQA iON (IBA Dosimetry) for proton therapy and its clinical implementation at the MedAustron Ion Therapy Center.

Imaging of pleural disease.

The pleural space is a "potential" anatomical space which is formed of two layers: visceral and parietal. It normally contains a trace of fluid (∼10 mL in each hemithorax). Diseases of the pleura can manifest with thickening of the pleural membranes or by abnormal accumulation of air or liquid.

Evaluation of a novel CBCT conversion method implemented in a treatment planning system.

Background: To evaluate a novel CBCT conversion algorithm for dose calculation implemented in a research version of a treatment planning system (TPS).

Methods: The algorithm was implemented in a research version of RayStation (v. 11B-DTK, RaySearch, Stockholm, Sweden).

Stereoscopic X-ray image and thermo-optical surface guidance for breast cancer radiotherapy in deep inspiration breath-hold.

Purpose: To investigate the feasibility of a thermo-optical surface imaging (SGRT) system combined with room-based stereoscopic X‑ray image guidance (IGRT) in a dedicated breast deep inspiration breath-hold (DIBH) irradiation workflow. In this context, benchmarking of portal imaging (EPID) and cone-beam CT (CBCT) against stereoscopic X‑rays was performed.

Methods: SGRT + IGRT data of 30 left-sided DIBH breast patients (1 patient with bilateral cancer) treated in 351 fractions using thermo-optical surface imaging and X-ray IGRT were retrospectively analysed.

Hyperthermia in the treatment of high-risk soft tissue sarcomas: a systematic review.

Background: The therapy of high-risk soft tissue sarcomas (STS) remains an interdisciplinary challenge. Regional hyperthermia (RHT) sparked interest as it has been shown to improve overall survival when added to perioperative chemotherapy (CTX). However, questions arise on how RHT should be optimally integrated into current multi-modal therapies.

Silicone phantoms fabricated with multi-material extrusion 3D printing technology mimicking imaging properties of soft tissues in CT.

Recently, 3D printing has been widely used to fabricate medical imaging phantoms. So far, various rigid 3D printable materials have been investigated for their radiological properties and efficiency in imaging phantom fabrication. However, flexible, soft tissue materials are also needed for imaging phantoms for simulating several clinical scenarios where anatomical deformations is important.

Technical and functional outcome after sacral neuromodulation using the "H" technique.

Background: Sacral neuromodulation (SNM) is a widely accepted treatment for pelvic floor disorders, including constipation and fecal incontinence (FI). In 2017, a standardized electrode placement method, the H technique, was introduced to minimize failure rates and improve clinical outcomes. We aimed to investigate the technical feasibility and functional outcome of the procedure.

Accelerating and improving radiochromic film calibration by utilizing the dose ratio in photon and proton beams.

Purpose: Radiochromic films are versatile 2D dosimeters with high-resolution and near tissue equivalence. To assure high precision and accuracy, a time-consuming calibration process is required. To improve the time efficiency, a novel calibration method utilizing the ratio of the same dose profile measured at different monitor units (MUs) is introduced and tested in a proton and photon beam.

ESTRO-ACROP guideline on surface guided radiation therapy.

Surface guidance systems enable patient positioning and motion monitoring without using ionising radiation. Surface Guided Radiation Therapy (SGRT) has therefore been widely adopted in radiation therapy in recent years, but guidelines on workflows and specific quality assurance (QA) are lacking. This ESTRO-ACROP guideline aims to give recommendations concerning SGRT roles and responsibilities and highlights common challenges and potential errors.

Early morbidity and dose-volume effects in definitive radiochemotherapy for locally advanced cervical cancer: a prospective cohort study covering modern treatment techniques.

Purpose: Predicting morbidity for patients with locally advanced cervix cancer after external beam radiotherapy (EBRT) based on dose-volume parameters remains an unresolved issue in definitive radiochemotherapy. The aim of this prospective study was to correlate patient characteristics and dose-volume parameters to various early morbidity endpoints for different EBRT techniques, including volumetric modulated arc therapy (VMAT) and adaptive radiotherapy (ART).

Methods And Materials: The study population consisted of 48 patients diagnosed with locally advanced cervix cancer, treated with definitive radiochemotherapy including image-guided adaptive brachytherapy (IGABT).

Investigation of the Bragg peak degradation caused by homogeneous and heterogeneous lung tissue substitutes: proton beam experiments and comparison to current clinical dose calculation.

Submillimetre structures of lung tissue are not represented in computed tomography images used for radiotherapeutic dose calculation. In order to study the effect experimentally, lung substitutes with properties similar to lung tissue were chosen, namely two types of commercial lung tissue equivalent plates (LTEPs) (CIRS, USA), two types of cork, balsawood, floral foam and konjac sponge. Laterally integrated dose profiles were measured as a function of depth for proton pencil beams (PBs) with an initial nominal energy of 97.

Grand challenges for medical physics in radiation oncology.

Medical physics has made considerable contributions to recent advances in radiation oncology. Medical physicists are key players in the clinical and scientific radiation oncology context due to their unique skill sets, flexibility, clinical involvement and intrinsic translational character. The continuing development and widespread adoption of "high-tech" radiotherapy has led to an increased need for medical physics involvement.

The practical radius of a pencil beam in proton therapy.

The central Gaussian shaped high dose region of a pencil beam (PB) in light ion beam therapy (LIBT) is enveloped by a low dose region causing non-negligible field size effects and impairs the dose calculation accuracy considerably if the low dose envelope is not well modeled. The purpose of this study was to calculate the practical radius, R, at which a PB does not influence a field more than a certain accuracy level. Lateral dose profiles of proton beams in water were simulated using GATE/Geant4.

MR-guided proton therapy: a review and a preview.

Background: The targeting accuracy of proton therapy (PT) for moving soft-tissue tumours is expected to greatly improve by real-time magnetic resonance imaging (MRI) guidance. The integration of MRI and PT at the treatment isocenter would offer the opportunity of combining the unparalleled soft-tissue contrast and real-time imaging capabilities of MRI with the most conformal dose distribution and best dose steering capability provided by modern PT. However, hybrid systems for MR-integrated PT (MRiPT) have not been realized so far due to a number of hitherto open technological challenges.

Technical Note: GATE-RTion: a GATE/Geant4 release for clinical applications in scanned ion beam therapy.

Purpose: GATE-RTion is a validated version of GATE for clinical use in the field of light ion beam therapy. This paper describes the GATE-RTion project and illustrates its potential through clinical applications developed in three European centers delivering scanned proton and carbon ion treatments.

Methods: GATE-RTion is a collaborative framework provided by the OpenGATE collaboration.

Time-resolved dosimetry for validation of 4D dose calculation in PBS proton therapy.

Four-dimensional dose calculation (4D-DC) is crucial for predicting the dosimetric outcome in the presence of intra-fractional organ motion. Time-resolved dosimetry can provide significant insights into 4D pencil beam scanning dose accumulation and is therefore irreplaceable for benchmarking 4D-DC. In this study a novel approach of time-resolved dosimetry using five PinPoint ionization chambers (ICs) embedded in an anthropomorphic dynamic phantom was employed and validated against beam delivery details.

Particle therapy in Europe.

Particle therapy using protons or heavier ions is currently the most advanced form of radiotherapy and offers new opportunities for improving cancer care and research. Ions deposit the dose with a sharp maximum - the Bragg peak - and normal tissue receives a much lower dose than what is delivered by X-ray therapy. Particle therapy has also biological advantages due to the high linear energy transfer of the charged particles around the Bragg peak.