Cardiac Exposure Related to Adjuvant Radiotherapy in Patients Affected by Thymoma: A Dosimetric Comparison of Photon or Proton Intensity-Modulated Therapy.

Background: Radiotherapy for thymoma is delivered post-operatively in selected cases. Given the particular location of the thymic bed and the excellent prognosis, late cardiac toxicities may be an issue. The purpose of this retrospective dosimetric study is to investigate whether intensity-modulated proton beam therapy (IMPT) compared to photon therapy could better spare cardiac substructures, given prespecified dose constraints.

Evaluation of ion recombination and polarity effect on photon depth dose measurements using mini- and micro-ion chamber.

Purpose: To investigate the effect of ion recombination ( ) and polarity ( ) correction factors on percentage depth dose (PDD) curves for three ion chambers, using flat and flattening filter free (FFF) beams, across different broad field sizes. A method to assess these effects and their corresponding corrections is proposed.

Methods: and were evaluated following the IAEA TRS-398 protocol for three ion chambers: PTW Semiflex-3D-31021, PinPoint-3D-31022, and Semiflex-31010.

Intensity Modulated Therapy for Patients With Breast Cancer. Practical Guidelines and Tips for an Effective Treatment Planning Strategy.

Purpose: Practical guidelines and tips for effective and robust radiation therapy treatment planning for patients with breast cancer are addressed for fixed-field intensity modulated radiation therapy (IMRT) or volumetric modulated arc therapy (VMAT) techniques. The concepts described here are general and valid on all treatment planning systems. However, some details shown here have been applied to the Varian platforms used at the authors' institutions.

Comparative dosimetric analysis of volumetric modulated arc therapy based craniospinal irradiation plans between Halcyon ring gantry and TrueBeam C-arm linear accelerator.

This study evaluates the volumetric modulated arc therapy (VMAT) dosimetric comparison between Halcyon ring gantry and TrueBeam c-arm linear accelerators for craniospinal irradiation (CSI) of the neuro-axis. 25 patients, who received treatment for medulloblastoma and primitive neuro-ectodermal tumors between 2018 and 2021, were planned for VMAT in True Beam (TB), and Halcyon (HAL) linear accelerators using 6 MV unflattened (FFF) photon beams (HALFFF and TBFFF). Dose-volume statistics for the target and organs at risk (OARs) and the total number of monitoring units (MUs) in the treatment plans were compared which included dose received by 95% PTV volume (V95%), volume receiving ≥ 107% dose, homogeneity index (HI), conformity index (PI), MU and dose spillage (D10%, D30%, D50%, D70%, D90%).

Predictive value of clinical and radiomic features for radiation therapy response in patients with lymph node-positive head and neck cancer.

Background: Prediction of survival and radiation therapy response is challenging in head and neck cancer with metastatic lymph nodes (LNs). Here we developed novel radiomics- and clinical-based predictive models.

Methods: Volumes of interest of LNs were employed for radiomic features extraction.

Knowledge-based DVH estimation and optimization for breast VMAT plans with and without avoidance sectors.

Background: To analyze RapidPlan knowledge-based models for DVH estimation of organs at risk from breast cancer VMAT plans presenting arc sectors en-face to the breast with zero dose rate, feature imposed during the optimization phase (avoidance sectors AS).

Methods: CT datasets of twenty left breast patients in deep-inspiration breath-hold were selected. Two VMAT plans, PartArc and AvoidArc, were manually generated with double arcs from ~ 300 to ~ 160°, with the second having an AS en-face to the breast to avoid contralateral breast and lung direct irradiation.

Training and validation of a knowledge-based dose-volume histogram predictive model in the optimisation of intensity-modulated proton and volumetric modulated arc photon plans for pleural mesothelioma patients.

Background: To investigate the performance of a narrow-scope knowledge-based RapidPlan (RP) model for optimisation of intensity-modulated proton therapy (IMPT) and volumetric modulated arc therapy (VMAT) plans applied to patients with pleural mesothelioma. Second, estimate the potential benefit of IMPT versus VMAT for this class of patients.

Methods: A cohort of 82 patients was retrospectively selected; 60 were used to "train" a dose-volume histogram predictive model; the remaining 22 provided independent validation.

Stereotactic Body Radiation Therapy for Lung Metastases From Sarcoma in Oligometastatic Patients: A Phase 2 Study.

Purpose: The lung is the most frequent site of metastasis in patients with sarcoma. Pulmonary metastasectomy is the most common treatment performed. Stereotactic body radiation therapy (SBRT) has proven to be a potential alternative to resection.

Preclinical validation and treatment of volumetric modulated arc therapy based total bone marrow irradiation in Halcyon™ ring gantry linear accelerator.

Aim: This study aims​ to report preclinical validation, and the first clinical treatment of total bone marrow irradiation (TMI) and total bone marrow and lymph nodal irradiation (TMLI) using Volumetric modulated arc therapy in Halcyon-E ring gantry linear accelerator. Preclinical validation includes simulation, planning, patient-specific QA, and dry run.

Material And Method: Four patients, two female and two male, with body weights of 116 kg, 52 kg, 64 kg, and 62 kg; with two with chronic myeloid leukemia, one each with acute lymphoblastic leukemia and acute myeloid leukemia (AML) were simulated and planned for TMI/TMLI.

Radiomics-based prognosis classification for high-risk prostate cancer treated with radiotherapy.

Objective: The present study aimed to investigate if CT-based radiomics features could correlate to the risk of metastatic progression in high-risk prostate cancer patients treated with radical RT and long-term androgen deprivation therapy (ADT).

Materials And Methods: A total of 157 patients were investigated and radiomics features extracted from the contrast-free treatment planning CT series. Three volumes were segmented: the prostate gland only (CTV_p), the prostate gland with seminal vesicles (CTV_psv), and the seminal vesicles only (CTV_sv).

Volumetric modulated arc therapy versus intensity-modulated proton therapy in the irradiation of infra diaphragmatic Hodgkin Lymphoma in female patients.

Purpose: To investigate the role of infra diaphragmatic intensity-modulated proton therapy (IMPT) compared to volumetric modulated arc therapy (VMAT) for female Hodgkin Lymphoma (HL) patients and to estimate the risk of secondary cancer and ovarian failure.

Methods: A comparative treatment planning study was performed on 14 patients, and the results were compared according to conventional dose-volume metrics. In addition, estimates of the excess absolute risk (EAR) of secondary cancer induction were determined for the bowel, the bladder and the rectum.

A novel external beam radiotherapy method for cervical cancer patients using virtual straight or bending boost areas; an in-silico feasibility study.

Aim: To investigate the potential role of a novel spatially fractionated radiation therapy (SFRT) method where heterogeneous dose patterns are created in target areas with virtual rods, straight or curving, of variable position, diameter, separation and alignment personalised to a patient's anatomy. The images chosen for this study were CT scans acquired for the external beam part of radiotherapy.

Methods: Ten patients with locally advanced cervical cancer were retrospectively investigated with SFRT.

Dosimetric impact of volumetric modulated arc therapy for nasopharyngeal cancer treatment.

Background: The purpose of the study was to evaluate the toxicity and outcome of nasopharyngeal carcinoma patients treated using 3-dimensional conformal radiotherapy (3DCRT) or volumetric modulated arc therapy (VMAT) technique.

Materials And Methods: 68 patients treated between 2006 and 2018 were retrospectively analysed. Since 2009 patients received 3DCRT with 50/70 Gy to the elective/boost volumes in 35 fractions; from then, VMAT with simultaneous integrated boost (SIB) with 54.

The Potential Role of Intensity-Modulated Proton Therapy in Hepatic Carcinoma in Mitigating the Risk of Dose De-Escalation.

Purpose: To investigate the role of intensity-modulated proton therapy (IMPT) for hepatocellular carcinoma (HCC) patients to be treated with stereotactic body radiation therapy (SBRT) in a risk-adapted dose prescription regimen.

Methods: A cohort of 30 patients was retrospectively selected as "at-risk" of dose de-escalation due to the proximity of the target volumes to dose-limiting healthy structures. IMPT plans were compared to volumetric modulated arc therapy (VMAT) RapidArc (RA) plans.

Knowledge-based intensity-modulated proton planning for gastroesophageal carcinoma.

Purpose: To investigate the performance of a narrow-scope knowledge-based RapidPlan (RP) model, for optimisation of intensity-modulated proton therapy (IMPT) plans applied to patients with locally advanced carcinoma in the gastroesophageal junction.

Methods: A cohort of 60 patients was retrospectively selected; 45 were used to 'train' a dose-volume histogram predictive model; the remaining 15 provided independent validation. The performance of the RP model was benchmarked against manual optimisation.

Dose coverage impacts local control in ultra-central lung oligometastases treated with stereotactic radiotherapy.

Introduction: The use of Stereotactic Body Radiotherapy (SBRT) is controversial in Ultra-Central lung tumors, a subset of central lung tumors characterized by proximity to critical mediastinal structures. This is of interest in oligometastatic (≤3 metastases) patients, who can yield survival benefit from local treatments. The aim of our study is to assess the determinants of efficacy and toxicity in this setting.

The role of a knowledge based dose-volume histogram predictive model in the optimisation of intensity-modulated proton plans for hepatocellular carcinoma patients : Training and validation of a novel commercial system.

Purpose: To investigate the performance of a knowledge-based RapidPlan, for optimisation of intensity-modulated proton therapy (IMPT) plans applied to hepatocellular cancer (HCC) patients.

Methods: A cohort of 65 patients was retrospectively selected: 50 were used to "train" the model, while the remaining 15 provided independent validation. The performance of the RapidPlan model was benchmarked against manual optimisation and was also compared to volumetric modulated arc therapy (RapidArc) photon plans.

Hypofractionated Whole Breast Irradiation and Simultaneous Integrated Boost in Large-breasted Patients: Long-term Toxicity and Cosmesis.

Introduction: The purpose of this study was to evaluate the impact of breast size on long-term toxicity and cosmesis in patients with breast cancer treated with hypofractionated simultaneous integrated boost (SIB) using volumetric modulated arc therapy (VMAT).

Patients And Methods: Patients with early stage breast cancer were treated with 3-week hypofractionated SIB-VMAT to the whole breast (40.5 Gy) and tumor bed (48 Gy).

Gantry-Mounted Linear Accelerator-Based Stereotactic Body Radiation Therapy for Low- and Intermediate-Risk Prostate Cancer.

Purpose: To establish the safety and efficacy of gantry-mounted linear accelerator-based stereotactic body radiation therapy (SBRT) for low- and intermediate-risk prostate cancer.

Methods: We pooled 921 patients enrolled on 7 single-institution prospective phase II trials of gantry-based SBRT from 2006 to 2017. The cumulative incidences of biochemical recurrence (defined by the Phoenix definition) and physician-scored genitourinary (GU) and gastrointestinal (GI) toxicities (defined per the original trials using Common Terminology Criteria for Adverse Events) were estimated using a competing risk framework.

Volumetric modulated arc therapy versus intensity-modulated proton therapy in the postoperative irradiation of thymoma.

Background: To investigate the role of intensity-modulated proton therapy (IMPT) compared to volumetric modulated arc therapy (VMAT) for the radiation treatment of thymoma cancer.

Methods: Twenty patients were retrospectively planned for IMPT [with (IMPT_R1 or IMPT_R2 according to the approach adopted) and without robust optimization] and VMAT. The results were compared according to dose-volume metrics on the clinical and planning target volumes (CTV and PTV) and the main organs at risk (heart, breasts, lungs, spinal cord and oesophagus).

Volumetric modulated arc therapy versus intensity-modulated proton therapy in neoadjuvant irradiation of locally advanced oesophageal cancer.

Background: To investigate the role of intensity-modulated proton therapy (IMPT) compared to volumetric modulated arc therapy (VMAT), realised with RapidArc and RapidPlan methods (RA_RP) for neoadjuvant radiotherapy in locally advanced oesophagal cancer.

Methods: Twenty patients were retrospectively planned for IMPT (with two fields, (IMPT_2F) or with three fields (IMPT_3F)) and RA_RP and the results were compared according to dose-volume metrics. Estimates of the excess absolute risk (EAR) of secondary cancer induction were determined for the lungs.

Computed tomography (CT)-derived radiomic features differentiate prevascular mediastinum masses as thymic neoplasms versus lymphomas.

Objectives: We aimed to assess the ability of radiomics, applied to not-enhanced computed tomography (CT), to differentiate mediastinal masses as thymic neoplasms vs lymphomas.

Methods: The present study was an observational retrospective trial. Inclusion criteria were pathology-proven thymic neoplasia or lymphoma with mediastinal localization, availability of CT.

PET/CT radiomics in breast cancer: Mind the step.

The aim of the present review was to assess the current status of positron emission tomography/computed tomography (PET/CT) radiomics research in breast cancer, and in particular to analyze the strengths and weaknesses of the published papers in order to identify challenges and suggest possible solutions and future research directions. Various combinations of the terms "breast", "radiomic", "PET", "radiomics", "texture", and "textural" were used for the literature search, extended until 8 July 2019, within the PubMed/MEDLINE database. Twenty-six articles fulfilling the inclusion/exclusion criteria were retrieved in full text and analyzed.

Intensity modulated proton therapy compared to volumetric modulated arc therapy in the irradiation of young female patients with hodgkin's lymphoma. Assessment of risk of toxicity and secondary cancer induction.

Background: To investigate the role of intensity modulated proton therapy (IMPT) compared to volumetric modulated arc therapy (VMAT) for advanced supradiaphragmatic Hodgkin's lymphoma (HL) in young female patients by assessing dosimetric features and modelling the risk of treatment related complications and radiation-induced secondary malignancies.

Methods: A group of 20 cases (planned according to the involved-site approach) were retrospectively investigated in a comparative planning study. Intensity modulated proton plans (IMPT) were compared to VMAT RapidArc plans (RA).