Accelerated Hypofractionated Chemoradiation Followed by Stereotactic Ablative Radiotherapy Boost for Locally Advanced, Unresectable Non-Small Cell Lung Cancer: A Nonrandomized Controlled Trial.

Importance: Intrathoracic progression remains the predominant pattern of failure in patients treated with concurrent chemoradiation followed by a consolidation immune checkpoint inhibitor for locally advanced, unresectable non-small cell lung cancer (NSCLC).

Objective: To determine the maximum tolerated dose (MTD) and use of hypofractionated concurrent chemoradiation with an adaptive stereotactic ablative radiotherapy (SABR) boost.

Design, Setting, And Participants: This was an early-phase, single-institution, radiation dose-escalation nonrandomized controlled trial with concurrent chemotherapy among patients with clinical stage II (inoperable/patient refusal of surgery) or III NSCLC (American Joint Committee on Cancer Staging Manual, seventh edition).

Review of cone beam computed tomography based online adaptive radiotherapy: current trend and future direction.

Adaptive radiotherapy (ART) was introduced in the late 1990s to improve the accuracy and efficiency of therapy and minimize radiation-induced toxicities. ART combines multiple tools for imaging, assessing the need for adaptation, treatment planning, quality assurance, and has been utilized to monitor inter- or intra-fraction anatomical variations of the target and organs-at-risk (OARs). Ethos™ (Varian Medical Systems, Palo Alto, CA), a cone beam computed tomography (CBCT) based radiotherapy treatment system that uses artificial intelligence (AI) and machine learning to perform ART, was introduced in 2020.

RapidPlan hippocampal sparing whole brain model version 2-how far can we reduce the dose?

Whole-brain radiotherapy has been the standard palliative treatment for patients with brain metastases due to its effectiveness, availability, and ease of administration. Recent clinical trials have shown that limiting radiation dose to the hippocampus is associated with decreased cognitive toxicity. In this study, we updated an existing Knowledge Based Planning model to further reduce dose to the hippocampus and improve other dosimetric plan quality characteristics.

Radiation Therapy for Prostate Cancer Using HYpofractionation Directed by UltraSound (RAPHYDUS): A Brazilian Public Health Care System Study.

Purpose: This study evaluated the toxicity associated with a short course dose-escalated hypofractionated radiation therapy (HFRT) using image guided RT with or without androgen suppression therapy in patients with prostate cancer.

Methods And Materials: This single-center prospective observational study included 132 patients with prostate cancer from 2016 to 2020. Patients received HFRT using image guided RT (84%) with 3-dimensional (91%) or intensity modulated RT (9%).

Interplay Between Duration of Androgen Deprivation Therapy and External Beam Radiotherapy With or Without a Brachytherapy Boost for Optimal Treatment of High-risk Prostate Cancer: A Patient-Level Data Analysis of 3 Cohorts.

Importance: Radiotherapy combined with androgen deprivation therapy (ADT) is a standard of care for high-risk prostate cancer. However, the interplay between radiotherapy dose and the required minimum duration of ADT is uncertain.

Objective: To determine the specific ADT duration threshold that provides a distant metastasis-free survival (DMFS) benefit in patients with high-risk prostate cancer receiving external beam radiotherapy (EBRT) or EBRT with a brachytherapy boost (EBRT+BT).

Performance of a Prostate-Specific Membrane Antigen Positron Emission Tomography/Computed Tomography-Derived Risk-Stratification Tool for High-risk and Very High-risk Prostate Cancer.

Importance: Prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) can detect low-volume, nonlocalized (ie, regional or metastatic) prostate cancer that was occult on conventional imaging. However, the long-term clinical implications of PSMA PET/CT upstaging remain unclear.

Objectives: To evaluate the prognostic significance of a nomogram that models an individual's risk of nonlocalized upstaging on PSMA PET/CT and to compare its performance with existing risk-stratification tools.

Patterns of Clinical Progression in Radiorecurrent High-risk Prostate Cancer.

The natural history of radiorecurrent high-risk prostate cancer (HRPCa) is not well-described. To better understand its clinical course, we evaluated rates of distant metastases (DM) and prostate cancer-specific mortality (PCSM) in a cohort of 978 men with radiorecurrent HRPCa who previously received either external beam radiation therapy (EBRT, n = 654, 67%) or EBRT + brachytherapy (EBRT + BT, n = 324, 33%) across 15 institutions from 1997 to 2015. In men who did not die, median follow-up after treatment was 8.

Identifying the Best Candidates for Prostate-specific Membrane Antigen Positron Emission Tomography/Computed Tomography as the Primary Staging Approach Among Men with High-risk Prostate Cancer and Negative Conventional Imaging.

Prostate-specific membrane antigen (PSMA) positron emission tomography (PET)/computed tomography (CT) is an emerging imaging modality with greater sensitivity and specificity over conventional imaging for prostate cancer (PCa) staging. Using data from two prospective trials (NCT03368547 and NCT04050215), we explored predictors of overall upstaging (nodal and metastatic) by PSMA PET/CT among patients with cN0M0 National Comprehensive Cancer Network high-risk PCa on conventional imaging (n = 213). Overall, 21.

Stereotactic Body Radiotherapy for High-Risk Localized Carcinoma of the Prostate (SHARP) Consortium: Analysis of 344 Prospectively Treated Patients.

Purpose: To explore the efficacy and toxicity of stereotactic body radiation therapy (SBRT) in high-risk prostate cancer (HRPCa) in a consortium of 7 institutional phase 2 trials and prospective registries.

Methods And Materials: Individual patient data were pooled for 344 patients with a minimum follow-up of 24 months. Biochemical recurrence-free survival (BCRFS) and distant metastasis-free survival (DMFS) were estimated using a Kaplan-Meier framework.

Dose-response with stereotactic body radiotherapy for prostate cancer: A multi-institutional analysis of prostate-specific antigen kinetics and biochemical control.

Background And Purpose: The optimal dose for prostate stereotactic body radiotherapy (SBRT) is still unknown. This study evaluated the dose-response relationships for prostate-specific antigen (PSA) decay and biochemical recurrence (BCR) among 4 SBRT dose regimens.

Materials And Methods: In 1908 men with low-risk (50.

Prostate-specific antigen kinetics and biochemical control following stereotactic body radiation therapy, high dose rate brachytherapy, and low dose rate brachytherapy: A multi-institutional analysis of 3502 patients.

Background And Purpose: Stereotactic body radiation therapy (SBRT), low dose rate brachytherapy (LDR-BT) and high dose rate brachytherapy (HDR-BT) are ablative-intent radiotherapy options for prostate cancer (PCa). These vary considerably in dose delivery, which may impact post-treatment prostate-specific antigen (PSA) patterns and biochemical control. We compared PSA kinetics between SBRT, HDR-BT, and LDR-BT, and assessed their relationships to biochemical recurrence-free survival (BCRFS).

The intraprostatic immune environment after stereotactic body radiotherapy is dominated by myeloid cells.

Background: Hundreds of ongoing clinical trials combine radiation therapy, mostly delivered as stereotactic body radiotherapy (SBRT), with immune checkpoint blockade. However, our understanding of the effect of radiotherapy on the intratumoral immune balance is inadequate, hindering the optimal design of trials that combine radiation therapy with immunotherapy. Our objective was to characterize the intratumoral immune balance of the malignant prostate after SBRT in patients.

Phase 1 Trial of Stereotactic Body Radiation Therapy Neoadjuvant to Radical Prostatectomy for Patients With High-Risk Prostate Cancer.

Purpose: This study aimed to evaluate the feasibility and safety of prostate stereotactic body radiation therapy (SBRT) neoadjuvant to radical prostatectomy (RP) in a phase 1 trial. The primary endpoint was treatment completion rate without severe acute surgical complications. Secondary endpoints included patient-reported quality of life and physician-reported toxicities.

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.

Development and Validation of a Comprehensive Multivariate Dosimetric Model for Predicting Late Genitourinary Toxicity Following Prostate Cancer Stereotactic Body Radiotherapy.

Dosimetric predictors of toxicity after Stereotactic Body Radiation Therapy (SBRT) are not well-established. We sought to develop a multivariate model that predicts Common Terminology Criteria for Adverse Events (CTCAE) late grade 2 or greater genitourinary (GU) toxicity by interrogating the entire dose-volume histogram (DVH) from a large cohort of prostate cancer patients treated with SBRT on prospective trials. Three hundred and thirty-nine patients with late CTCAE toxicity data treated with prostate SBRT were identified and analyzed.

Clinical Assessment of Prostate Displacement and Planning Target Volume Margins for Stereotactic Body Radiotherapy of Prostate Cancer.

To assess the optimal planning target volume (PTV) margins for stereotactic body radiotherapy (SBRT) of prostate cancer based on inter- and intra-fractional prostate motion determined from daily image guidance. Two hundred and five patients who were enrolled on two prospective studies of SBRT (8 Gy × 5 fractions) for localized prostate cancer treated at a single institution between 2012 and 2017 had complete inter- and intra-fractional shift data available. All patients had scheduled kilovoltage planar imaging during SBRT with rigid registration to intraprostatic fiducials prior to each of four half-arcs delivered per fraction, as well as cone beam CT verification of anatomy prior to each fraction.

A Prospective Multi-Institutional Phase I/II Trial of Step-Wise Dose-per-Fraction Escalation in Low and Intermediate Risk Prostate Cancer.

Purpose: This phase I/II, multi-institutional trial explored the tolerance and efficacy of stepwise increasing hypofractionation (HPFX) radiation therapy regimens for fraction sizes up to 4.3 Gy in localized prostate cancer.

Methods And Materials: Three escalating dose-per-fraction schedules were designed to yield similar predicted tumor control while maintaining equivalent predicted late toxicity.

Local Failure and Survival After Definitive Radiotherapy for Aggressive Prostate Cancer: An Individual Patient-level Meta-analysis of Six Randomized Trials.

Background: The importance of local failure (LF) after treatment of high-grade prostate cancer (PCa) with definitive radiotherapy (RT) remains unknown.

Objective: To evaluate the clinical implications of LF after definitive RT.

Design, Setting, And Participants: Individual patient data meta-analysis of 992 patients (593 Gleason grade group [GG] 4 and 399 GG 5) enrolled in six randomized clinical trials.

Association between Long-Term Second Malignancy Risk and Radiation: A Comprehensive Analysis of the Entire Surveillance, Epidemiology, and End Results Database (1973-2014).

Purpose: Second malignancies (SMs) after radiation therapy are rare but serious sequelae of treatment. This study investigates whether radiation therapy use is associated with changes in baseline SM risk.

Methods And Materials: We extracted all patients with cancer, with or without SM, in the Surveillance, Epidemiology, and End Results database from 1973 to 2014.

Underutilization of Androgen Deprivation Therapy with External Beam Radiotherapy in Men with High-grade Prostate Cancer.

Multiple randomized trials have shown a survival benefit to long durations of androgen deprivation therapy (ADT) in patients with Gleason grade group (GG) 4-5 (ie, Gleason score 8-10) prostate cancer (PCa) undergoing definitive external beam radiotherapy (EBRT). We conducted a population-based retrospective study utilizing the complete Surveillance, Epidemiology, and End Results (SEER)-Medicare-linked database from 2008 to 2011, extracting PCa patients of non-Hispanic white (NHW) and African-American (AA) race diagnosed with GG 4-5PCa who received EBRT with or without concomitant ADT. Of 961 patients receiving definitive EBRT, 225 (23.

Multi-Institutional Analysis of Prostate-Specific Antigen Kinetics After Stereotactic Body Radiation Therapy.

Purpose: Understanding prostate-specific antigen (PSA) kinetics after radiation therapy plays a large role in the management of patients with prostate cancer (PCa). This is particularly true in establishing expectations regarding PSA nadir (nPSA) and PSA bounces, which can be disconcerting. As increasingly more patients are being treated with stereotactic body radiation therapy (SBRT) for low- and intermediate-risk PCa, it is imperative to understand the PSA response to SBRT.

Testosterone Levels and Sexual Quality of Life After Stereotactic Body Radiation Therapy for Prostate Cancer: A Multi-Institutional Analysis of Prospective Trials.

Purpose: The impact of higher scatter doses per fraction on testicular function and quality of life after prostate stereotactic body radiation therapy (SBRT) is poorly studied.

Methods And Materials: Six hundred thirty-six patients treated with SBRT for low- to intermediate-risk prostate cancer from 2009 to 2014 were included. Changes in testosterone and in sexual and hormonal domain scores on the Expanded Prostate Cancer Index Composite-26 (EPIC) questionnaire over a 24-month period were evaluated via a 1-sided t test.

Prostate-only Versus Whole-pelvis Radiation with or Without a Brachytherapy Boost for Gleason Grade Group 5 Prostate Cancer: A Retrospective Analysis.

Background: The role of elective whole-pelvis radiotherapy (WPRT) remains controversial. Few studies have investigated it in Gleason grade group (GG) 5 prostate cancer (PCa), known to have a high risk of nodal metastases.

Objective: To assess the impact of WPRT on patients with GG 5 PCa treated with external-beam radiotherapy (EBRT) or EBRT with a brachytherapy boost (EBRT+BT).