Embracing the Future of Clinical Trials in Radiotherapy: An NRG Oncology CIRO Technology Retreat Whitepaper on Pioneering Technologies and AI-Driven Solutions.

This white paper examines the potential of pioneering technologies and artificial intelligence (AI)-driven solutions in advancing clinical trials involving radiotherapy. As the field of radiotherapy evolves, the integration of cutting-edge approaches such as radiopharmaceutical dosimetry, FLASH radiotherapy, image-guided radiation therapy (IGRT), and AI promises to improve treatment planning, patient care, and outcomes. Additionally, recent advancements in quantum science, linear energy transfer/relative biological effect (LET/RBE), and the combination of radiotherapy and immunotherapy create new avenues for innovation in clinical trials.

Postoperative Radiotherapy ± Cetuximab for Intermediate-Risk Head and Neck Cancer.

Purpose: Radiotherapy (RT)/cetuximab (C) demonstrated superiority over RT alone for locally advanced squamous head and neck cancer. We tested this in completely resected, intermediate-risk cancer.

Methods: Patients had squamous cell carcinoma of the head and neck (SCCHN) of the oral cavity, oropharynx, or larynx, with one or more risk factors warranting postoperative RT.

Derivation of a comprehensive semi-empirical proton RBE model from published experimental cell survival data collected in the PIDE database.

We aimed to develop a comprehensive proton relative biological effectiveness (RBE) model based on accumulated cell survival data in the literature. Our approach includes four major components: (1) Eligible cell survival data with various linear energy transfers (LETs) in the Particle Irradiation Data Ensemble (PIDE) database (72 datasets in four cell lines); (2) a cell survival model based on Poisson equation, with and defined as the ability to generate and repair damage, respectively, to replace the classic linear-quadratic model for fitting the cell survival data; (3) hypothetical linear relations of and on LET, or and ; and (4) a multi-curve fitting (MCF) approach to fit all cell survival data into the survival model and derive the , , , and values for each cell line. Dependences of these parameters on cell type were thus determined and finally a comprehensive RBE model was derived.

Primary Results of NRG-RTOG1106/ECOG-ACRIN 6697: A Randomized Phase II Trial of Individualized Adaptive (chemo)Radiotherapy Using Midtreatment F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Stage III Non-Small Cell Lung Cancer.

Purpose: NRG-RTOG0617 demonstrated a detrimental effect of uniform high-dose radiation in stage III non-small cell lung cancer. NRG-RTOG1106/ECOG-ACRIN6697 (ClinicalTrials.gov identifier: NCT01507428), a randomized phase II trial, studied whether midtreatment F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) can guide individualized/adaptive dose-intensified radiotherapy (RT) to improve and predict outcomes in patients with this disease.

A Pilot Trial of Proton-Based Cardiac Sparing Accelerated Fractionated Radiation Therapy in Unresectable Non-small Cell Lung Cancer With Extended Durvalumab Therapy (PARTICLE-D).

Purpose: Concurrent chemoradiation therapy is the current nonsurgical standard of care for locally advanced non-small cell lung cancer. However, this is a difficult regimen to tolerate, especially for those who are elderly, have multiple comorbidities, or have poor performance status. Alternative treatment regimens are needed for this vulnerable population.

Single institution experience of MRI-guided radiotherapy for thoracic tumors and clinical characteristics impacting treatment duty cycle.

Introduction: MRI-guided radiotherapy (MRgRT) allows for direct motion management and real-time radiation treatment plan adaptation. We report our institutional experience using low strength 0.35T MRgRT for thoracic malignancies, and evaluate changes in treatment duty cycle between first and final MRgRT fractions.

Outcomes of initial therapy for synchronous brain metastases from small cell lung cancer: a single-institution retrospective analysis.

Small cell lung cancer (SCLC) has a propensity for brain metastases, which is associated with poor prognosis. We sought to determine predictors of overall survival (OS) and brain progression-free survival (bPFS) in SCLC patients with synchronous brain metastases at the time of initial SCLC diagnosis. A total of 107 SCLC patients with synchronous brain metastases treated at a single institution were included in this retrospective analysis.

The Impact of Prophylactic Cranial Irradiation and Consolidative Thoracic Radiation Therapy for Extensive Stage Small-Cell Lung Cancer in the Transition to the Chemo-Immunotherapy Era: A Single Institution Series.

Introduction: Extensive-stage small-cell lung cancer (ES-SCLC) continues to have poor survival due to its aggressive behavior, despite improvements with incorporation of immunotherapy with standard chemotherapy. Controversy exists regarding the role of consolidative thoracic radiation therapy (TRT) and prophylactic cranial irradiation (PCI) in ES-SCLC due to high recurrence rates. We report our institutional result of the benefit of PCI and TRT in ES-SCLC.

Safety of Nivolumab Added to Chemoradiation Therapy Platforms for Intermediate and High-Risk Locoregionally Advanced Head and Neck Squamous Cell Carcinoma: RTOG Foundation 3504.

Purpose: Programmed death-1 immune checkpoint blockade improves survival of patients with recurrent/metastatic head and neck squamous cell carcinoma (HNSCC), but the benefits of addition to (chemo)radiation for newly diagnosed patients with HNSCC remain unknown.

Methods And Materials: We evaluated the safety of nivolumab concomitant with 70 Gy intensity modulated radiation therapy and weekly cisplatin (arm 1), every 3-week cisplatin (arm 2), cetuximab (arm 3), or alone for platinum-ineligible patients (arm 4) in newly diagnosed intermediate- or high-risk locoregionally advanced HNSCC. Patients received nivolumab from 2 weeks prior to radiation therapy until 3 months post-radiation therapy.

Low-risk meningioma: Initial outcomes from NRG Oncology/RTOG 0539.

Background: Three- and five-year progression-free survival (PFS) for low-risk meningioma managed with surgery and observation reportedly exceeds 90%. Herewith we summarize outcomes for low-risk meningioma patients enrolled on NRG/RTOG 0539.

Methods: This phase II trial allocated patients to one of three groups per World Health Organization grade, recurrence status, and resection extent.

A volume-independent conformity index for stereotactic radiosurgery.

Purpose: To develop a volume-independent conformity metric called the Gaussian Weighted Conformity Index (GWCI) to evaluate stereotactic radiosurgery/radiotherapy (SRS/SRT) plans for small brain tumors.

Methods: A signed bi-directional local distance (BLD) between the prescription isodose line and the target contour is determined for each point along the tumor contour (positive distance represents under-coverage). A similarity score function (SF) is derived from Gaussian function, penalizing under- and over-coverage at each point by assigning standard deviations of the Gaussian function.

A Comparative Study of Patients With Early-Stage Non-Small Cell Lung Cancer Treated With Stereotactic Body Radiation Therapy Using CyberKnife and Linear Accelerator-Based Volumetric Modulated Arc Therapy.

Purpose: Stereotactic body radiation therapy (SBRT) has become the standard of care for medically inoperable early-stage non-small cell lung cancer. We investigated 2 modalities of lung SBRT, CyberKnife (CK) and volumetric modulated arc therapy (VMAT), for differences in dosimetric parameters, tumor control, and clinical outcomes.

Methods And Materials: Patients who underwent SBRT for T1-2N0M0 non-small cell lung cancer from 2012 to 2018 were included.

Proton Beam Therapy for Locally Advanced Head and Neck Tumors: An Analysis of Dosimetric and Clinical Outcomes.

Objective: Locally advanced tumors of the head and neck region often lie in close proximity to critical organs at risk (OARs). Providing effective treatment coverage to these malignancies while minimizing radiation dose to surrounding OARs is advantageous. Our aim is to compare dosimetric data of OARs from proton beam therapy (PBT) plans to volumetric modulated arc therapy (VMAT) treatment plans, and to evaluate clinical outcomes in patients treated with PBT.

Higher Radiation Dose to the Immune Cells Correlates with Worse Tumor Control and Overall Survival in Patients with Stage III NSCLC: A Secondary Analysis of RTOG0617.

: We hypothesized that the Effective radiation Dose to the Immune Cells (EDIC) in circulating blood is a significant factor for the treatment outcome in patients with locally advanced non-small-cell lung cancer (NSCLC). : This is a secondary study of a phase III trial, NRG/RTOG 0617, in patients with stage III NSCLC treated with radiation-based treatment. The EDIC was computed as equivalent uniform dose to the entire blood based on radiation doses to all blood-containing organs, with consideration of blood flow and fractionation effect.

Pretreatment neutrophil-to-lymphocyte ratio as an important prognostic marker in stage III locally advanced non-small cell lung cancer: confirmatory results from the PROCLAIM phase III clinical trial.

Background: Neutrophil-to-lymphocyte ratio (NLR) is an important pretreatment marker of systemic inflammation and tumor aggressiveness. Increased levels of this ratio have been associated with reduced survival in several observational studies of lung cancer. However, supporting analyses from large clinical trial data are lacking.

Independently validated sex-specific nomograms for predicting survival in patients with newly diagnosed glioblastoma: NRG Oncology RTOG 0525 and 0825.

Background/purpose: Glioblastoma (GBM) is the most common primary malignant brain tumor. Sex has been shown to be an important prognostic factor for GBM. The purpose of this study was to develop and independently validate sex-specific nomograms for estimation of individualized GBM survival probabilities using data from 2 independent NRG Oncology clinical trials.

Adding Base-Excision Repair Inhibitor TRC102 to Standard Pemetrexed-Platinum-Radiation in Patients with Advanced Nonsquamous Non-Small Cell Lung Cancer: Results of a Phase I Trial.

Purpose: TRC102, a small-molecule base-excision repair inhibitor, potentiates the cytotoxicity of pemetrexed and reverses resistance by binding to chemotherapy-induced abasic sites in DNA. We conducted a phase I clinical trial combining pemetrexed and TRC102 with cisplatin-radiation in stage III nonsquamous non-small cell lung cancer (NS-NSCLC).

Patients And Methods: Fifteen patients were enrolled from 2015 to 2019.

Monte Carlo Dose Calculation Using MRI Based Synthetic CT Generated by Fully Convolutional Neural Network for Gamma Knife Radiosurgery.

The aim of this work is to study the dosimetric effect from generated synthetic computed tomography (sCT) from magnetic resonance (MR) images using a deep learning algorithm for Gamma Knife (GK) stereotactic radiosurgery (SRS). The Monte Carlo (MC) method is used for dose calculations. Thirty patients were retrospectively selected with our institution IRB's approval.

Stereotactic body radiotherapy (SBRT) for T2N0 (>3 cm) non-small cell lung cancer: Outcomes and failure patterns.

Purpose/objectives: Outcomes of T2N0 lung cancer patients treated with stereotactic radiotherapy are not well known.

Methods And Materials: We conducted a single institution retrospective review of patients with T2N0 NSCLC who were treated with SBRT. The local, regional, distant control rates were calculated from available clinical data.

Focal Prostate Stereotactic Body Radiation Therapy With Correlative Pathological and Radiographic-Based Treatment Planning.

Introduction: Advances in multiparametric MRI (mpMRI) combining anatomic and functional imaging can accurately identify foci of adenocarcinoma within the prostate, offering the possibility of partial gland therapy. We performed tandem prospective pilot trials to investigate the feasibility of focal prostate SBRT (f-SBRT) based on correlating diagnostic mpMRI and biopsies with confirmatory pathology in treatment planning.

Materials And Methods: Patients with pathologic focal Gleason 6-7 disease and a corresponding PIRADS 4-5 lesion on mpMRI underwent targeted and comprehensive biopsies using MRI/ultrasound fusion under electromagnetic sensor navigation.

Radiotherapy and Receptor Tyrosine Kinase Inhibition for Solid Cancers (ROCKIT): A Meta-Analysis of 13 Studies.

Background: We hypothesized that the addition of receptor tyrosine kinase inhibitors (RTKis, e.g., lapatinib, erlotinib, cetuximab, bevacizumab, panitumumab) to radiotherapy-based treatment for solid tumors does not increase overall survival but may increase toxicity.

Impact of effective dose to immune cells (EDIC) on lymphocyte nadir and survival in limited-stage SCLC.

Background: Effective dose to immune cell (EDIC), an estimated radiation dose to the circulating lymphocytes, is of significance for overall survival (OS) in non-small cell lung cancer. This study aimed to validate the EDIC's OS effect on limited-stage small cell lung cancer (LS-SCLC).

Method And Materials: This study included LS-SCLC patients received definitive chemo-radiation in one single center from 2012 to 2017.

Role of radiation in extensive stage small cell lung cancer: a National Cancer Database registry analysis.

The role of prophylactic cranial irradiation (PCI) and thoracic radiation therapy (TRT) in extensive-stage small cell lung cancer remains controversial. The authors examined the National Cancer Database and identified patients with extensive-stage small cell lung cancer with no brain metastasis. Patients were excluded if they died 30 days from diagnosis, did not receive polychemotherapy, had other palliative radiation or had missing information.

Proton Beam Therapy in the Treatment of Periorbital Malignancies.

Purpose: Periorbital tumor location presents a significant challenge with 3-dimensional conformal radiation therapy or intensity modulated radiation therapy due to high tumor dose needed in the setting of close proximity to orbital structures with lower tolerance. Proton beam therapy (PBT) is felt to be an effective modality in such cases due to its sharp dose gradient.

Materials And Methods: We reviewed our institutional PBT registry and identified 17 patients with tumor epicenters within 2 cm of the eye and optic apparatus treated with passive scatter PBT with comparison volumetric arc therapy plans available.