News | Image Guided Radiation Therapy (IGRT) | August 19, 2019

MRIdian System Limits Early Toxicity for Prostate Cancer Without Implanted Markers

Study shows low incidence of early toxicity using stereotactic body radiation therapy while eliminating potential complications and costs associated with implanted markers

MRIdian System Limits Early Toxicity for Prostate Cancer Without Implanted Markers

August 19, 2019 — ViewRay Inc. announced the acceptance of publication by the International Journal of Radiation Oncology, Biology and Physics of the first prospective clinical trial of MR-guided radiation therapy (MRgRT) in patients with localized prostate cancer. This robust study of clinician and patient reported outcomes demonstrated zero CTCAE v4 grade 3 or higher gastrointestinal (GI) and genitourinary (GU) toxicity and even lower incidence of grade 2 toxicity than investigators hypothesized. It is also one of the first prospective clinical trials to study stereotactic body radiation therapy (SBRT) in a mix of intermediate- and high-risk prostate cancer patients, a challenging patient population to treat. The journal is the official scientific journal of the American Society for Radiation Oncology (ASTRO).

Researchers from Amsterdam University Medical Center enrolled 101 patients with intermediate- or high-risk prostate cancer in a prospective phase II clinical trial. All patients received MRgRT in five fractions of 7.25 Gy to the target volume using on-table adaptive techniques. The trial did not use implanted markers or tissue spacers because treatments were delivered under magnetic resonance (MR)-guidance, thereby eliminating an invasive procedure, potentially associated complications and implantation costs. 

Results at three months showed that no early CTCAE v4.0 grade 3 GU or GI toxicity was observed, and the maximum cumulative grade 2 early GU and GI toxicity measured by any symptom at any study time point was 23.8 percent (study hypothesis 40 percent) and 5 percent (study hypothesis 15 percent). These results were obtained in a complex clinical cohort (59.4 percent high-risk patients) and are comparable to what would be typically observed in lower-risk populations, pointing to the potential benefits of MR-guided SBRT in this higher risk group. Additionally, the low incidence of early GI toxicity, despite the inclusion of the base of the seminal vesicles in 96 percent of patients, illustrates the benefit of MR-guidance and on-table adaptive re-planning. This technology facilitates smaller treatment margins while minimizing damage to surrounding tissue and critical structures, such as urethra, rectum and bladder. The publication noted that incontinence was uncommon, reported by 4 percent of patients at the end of MRgRT and decreasing over time.

"SBRT offers significant promise in the treatment of prostate cancer. Our clinical trial takes that a step further in showcasing its value in patients with intermediate- and high-risk disease, with a focus on evaluating associated toxicities and quality of life outcomes," said principal investigator Anna Bruynzeel, M.D., Ph.D., radiation oncologist at Amsterdam UMC. "We see a lower incidence of GI and GU toxicity with MR-guidance as compared to similar SBRT prostate cancer studies. The results reinforce the value of MRIdian's real-time on-table adaptive treatment with automatic beam gating for prostate patients."

For more information: www.redjournal.org

Related Content

VIDEO: Walk Through of the MRI Radiotherapy System at Henry Ford Hospital

FDA Clears Advancements for Viewray MRIdian Radiation Therapy System

Reference

Bruynzeel A.M.E., Tetar S.U., Oei S.S., et al. A prospective single-arm phase II study of stereotactic magnetic-resonance-guided adaptive radiotherapy for prostate cancer: Early toxicity results. International Journal of Radiation Oncology Biology Physics, published online Aug. 13, 2019. https://doi.org/10.1016/j.ijrobp.2019.08.007

Related Content

Members of Congress from both sides of the aisle issued a series of oversight letters to the Centers for Medicare and Medicaid Services (CMS) in recent months to urge the Agency to adjust its proposed radiation oncology advanced alternative payment model (RO Model)

Image by whitfieldink from Pixabay

News | Radiation Oncology | November 13, 2019
November 13, 2019 — Members of Congress from both sides of the aisle issued a series of oversight letters to the...
An image on Brigham and Women's Hospital's 7T MRI system

An image on Brigham and Women's Hospital's 7T MRI system. Image courtesy of Brigham and Women's Hospital

News | Magnetic Resonance Imaging (MRI) | November 13, 2019
November 13, 2019 — Increased immune system activity along the surface of the brain, or meningeal inflammation, may b
Radiographer Apollo Exconde with his Lego concept open MRI for patient education.

Radiographer Apollo Exconde with his Lego concept open MRI for patient education.

News | Patient Engagement | November 11, 2019
November 11, 2019 — Radiographer Apollo Exconde...
Image by Dr. Manuel González Reyes from Pixabay

Image by Dr. Manuel González Reyes from Pixabay 

News | SPECT Imaging | November 08, 2019
November 8, 2019 — Using ground-breaking technology, researchers at the...
This chest X-ray of a patient being treated for e-cigarette or vaping-associated lung injury shows lung opacities, densities and whitish cloud-like areas which are typically seen with unusual pneumonias, fluid in lungs or lung inflammation. Image courtesy of Intermountain Healthcare

This chest X-ray of a patient being treated for e-cigarette or vaping-associated lung injury shows lung opacities, densities and whitish cloud-like areas which are typically seen with unusual pneumonias, fluid in lungs or lung inflammation. Image courtesy of Intermountain Healthcare

News | Clinical Trials | November 08, 2019
November 8, 2019 — As the outbreak of lung injuries and deaths associated with e-cigarettes, or...
Unlike other technologies for imaging the placenta, pCASL MRI can distinguish maternal blood from fetal blood

Image courtesy of Pixabay

News | Clinical Trials | November 07, 2019
November 7, 2019 — A new imaging technique to track
Bladder Abdomen Pelvis image with DLCExpert
News | Artificial Intelligence | November 07, 2019
November 7, 2019 — Mirada Medical, a global leader in...
The introduction of liquid helium free, high-end MRI systems by MR Solutions substantially reduces the environmental impact
News | Magnetic Resonance Imaging (MRI) | November 05, 2019
November 5, 2019 — Environmental impact is becoming a significant factor in the selection of suppliers even in precli
MRI control room at Centra DuPage Hospital
News | Magnetic Resonance Imaging (MRI) | November 04, 2019
November 4, 2019 — Traditional image-guided procedures remained restricted to the limitation of physicians referring
Liver cancer tumor scanning using an MRI
News | Proton Therapy | November 04, 2019
November 4, 2019 – Two new studies support and inform the use of proton radiation therapy to treat patients with hepa