Stereotactic reirradiation with Cyberknife for locally recurrent prostate cancer, long-term toxicity and clinical outcomes from a monocentric cohort.

Purpose: Up to 47% of patients with localized prostate cancer (PCa) treated with radiotherapy (EBRT) eventually develop local recurrence. To date, no clear consensus exists on optimal management. A growing body of interest supports the use of stereotaxic re-irradiation (rSBRT), with promising oncological outcomes and low toxicity profile.

Preoperative single fraction breast radiotherapy: Intra-fraction geometric uncertainties and dosimetric implications.

Purpose: A preoperative breast robotic radiosurgery trial was concluded in our centre. Purposes of the present study were to evaluate retrospectively over the enrolled patients: i) respiratory patterns ii) tracking uncertainties iii) necessity of respiratory compensation iv) tracking errors dosimetric effects.

Methods: 22 patients were treated in 21 Gy single fraction using CyberKnife (CK) respiratory modelling and tracking (SynchronyResp) and data extracted from log-files.

Preoperative robotic radiosurgery for early breast cancer: Results of the phase II ROCK trial (NCT03520894).

Background And Purpose: Preoperative partial breast irradiation (PBI) has got the advantage of treating a well-defined target. We report the results of the phase II ROCK trial (NCT03520894), enrolling early breast cancer (BC) patients treated with preoperative robotic radiosurgery (prRS), in terms of acute and early late toxicity, disease control, and cosmesis.

Material And Methods: The study recruited between 2018 and 2021 at our Radiation Oncology Unit.

Robotic MLC-based plans: A study of plan complexity.

Purpose: The utility of complexity metrics has been assessed for IMRT and VMAT treatment plans, but this analysis has never been performed for CyberKnife (CK) plans. The purpose of this study is to perform a complexity analysis of CK MLC plans, adapting and computing complexity indices previously defined for IMRT plans. Metrics were used to compare the complexity of plans created by two optimization systems and to study correlations between plan complexity and patient-specific quality assurance (PSQA) results.

Performance assessment of a new optimization system for robotic SBRT MLC-based plans.

Purpose: To assess the performance of a new optimization system, VOLO, for CyberKnife MLC-based SBRT plans in comparison with the existing Sequential optimizer.

Methods: MLC-plans were created for 25 SBRT cases (liver, prostate, pancreas and spine) using both VOLO and Sequential. Monitor units (MU), delivery time (DT), PTV coverage, conformity (nCI), dose gradient (R50%) and OAR doses were used for comparison and combined to obtain a mathematical score (MS) of plan quality for each solution.

CyberKnife MLC-based treatment planning for abdominal and pelvic SBRT: Analysis of multiple dosimetric parameters, overall scoring index and clinical scoring.

Purpose: This study evaluated the plan quality of CyberKnife MLC-based treatment planning in comparison to the Iris collimator for abdominal and pelvic SBRT. Multiple dosimetric parameters were considered together with a global scoring index validated by clinical scoring.

Methods And Materials: Iris and MLC plans were created for 28 liver, 15 pancreas and 13 prostate cases including a wide range of PTV sizes (24-643 cm).

SBRT planning for spinal metastasis: indications from a large multicentric study.

Background: The dosimetric variability in spine stereotactic body radiation therapy (SBRT) planning was investigated in a large number of centres to identify crowd knowledge-based solutions.

Methods: Two spinal cases were planned by 48 planners (38 centres). The required prescription dose (PD) was 3 × 10 Gy and the planning target volume (PTV) coverage request was: V > 90% (minimum request: V > 80%).

Treatment planning for spinal radiosurgery : A competitive multiplatform benchmark challenge.

Purpose: To investigate the quality of treatment plans of spinal radiosurgery derived from different planning and delivery systems. The comparisons include robotic delivery and intensity modulated arc therapy (IMAT) approaches. Multiple centers with equal systems were used to reduce a bias based on individual's planning abilities.

CyberKnife beam output factor measurements: A multi-site and multi-detector study.

Purpose: New promising detectors are available for measuring small field size output factors (OFs). This study focused on a multicenter evaluation of two new generation detectors for OF measurements on CyberKnife systems.

Methods: PTW-60019 microDiamond and W1 plastic scintillation detector (PSD) were used to measure OFs on eight CyberKnife units of various generations for 5-60mm fixed cones.

Stereotactic body radiotherapy with CyberKnife for cardiac malignancies.

Aims And Background: Radiobiological and technical considerations have traditionally limited the role of radiation therapy in the context of primary and secondary cardiac malignancies. Stereotactic body radiotherapy (SBRT) is a promising modality for the delivery of focused high-dose radiation with ablative potential to complex targets such as small, deep-seated, moving lesions, allowing also for re-irradiation.

Methods: Between January 2013 and October 2013, 3 patients underwent SBRT for cardiac lesions: 2 patients had recurrent, previously irradiated cardiac angiosarcomas (PCA) and 1 patient had a cardiac metastasis from melanoma.

Salvage stereotactic re-irradiation with CyberKnife for locally recurrent head and neck cancer: a single center experience.

Aims And Background: We report the toxicity and preliminary clinical outcome in patients affected by locally recurrent head and neck cancer treated with stereotactic re-irradiation.

Methods: Between February 2012 and August 2013, 17 patients were treated with CyberKnife as stereotactic re-irradiation for locally recurrent head and neck cancer. All patients had previously received a full dose radiation treatment with radical intent, with a median total dose of 66 Gy (range, 50-70) delivered with standard fractionation.

Clinical outcome of stereotactic body radiotherapy for abdominal lymph node metastases.

Aims and background. To report the clinical outcome of linac-based or robotic, image-guided stereotactic body radiotherapy in patients affected by abdominal lymph node metastases from different primary cancers. Methods and methods.

Impact of plan parameters on the dosimetric accuracy of volumetric modulated arc therapy.

Purpose: To evaluate the effect of plan parameters on volumetric modulated arc therapy (VMAT) dosimetric accuracy, together with the possibility of scoring plan complexity.

Methods: 142 clinical VMAT plans initially optimized using a 4° control point (CP) separation were evaluated. All plans were delivered by a 6 MV Linac to a biplanar diode array for patient-specific quality assurance (QA).

Stereotactic radiotherapy for adrenal gland metastases: university of Florence experience.

Purpose: To evaluate a retrospective single-institution outcome after hypofractionated stereotactic body radiotherapy (SBRT) for adrenal metastases.

Methods And Materials: Between February 2002 and December 2009, we treated 48 patients with SBRT for adrenal metastases. The median age of the patient population was 62.

On-line image guidance for frameless stereotactic radiotherapy of lung malignancies by cone beam CT: comparison between target localization and alignment on bony anatomy.

Introduction: Free-breathing stereotactic radiotherapy for lung malignancies requires reliable prediction of respiratory motion and accurate target localization. A protocol was adopted for reproducibility and reduction of respiratory motion and for target localization by CBCT image guidance. Tumor respiratory displacements and tumor positioning errors relative to bony anatomy alignment are analyzed.