The integration of Magnetic Resonance Imaging (MRI) with linear accelerators (MRLs) is set to revolutionize the treatment of central nervous system (CNS) tumors. This cutting-edge approach aims to improve the precision of radiotherapy and significantly reduce neurotoxicity by adapting treatment plans based on daily anatomical changes. This innovation could change the game for patients with CNS tumors, offering them a more personalized and effective therapy.
Researchers from the H. Lee Moffitt Cancer Center and Research Institute, led by Dr. John Bryant and Dr. Daniel Oliver, have explored the potential of MRLs in enhancing CNS tumor treatment. Published in the journal Cancers, their review highlights how MRI’s superior soft tissue contrast aids in accurately visualizing tumors and nearby organs at risk. This allows for real-time adjustments to radiotherapy, ensuring precise dose delivery and minimizing damage to healthy tissue.
Dr. Bryant emphasized the transformative potential of this technology: “MRI provides excellent visualization of CNS tumors due to its superior soft tissue contrast, making it essential in the diagnosis and treatment planning of these malignancies.” This technology enables adaptive magnetic resonance-guided radiotherapy (MRgRT), allowing clinicians to modify treatment plans daily based on the latest anatomical data.
A significant application of MRLs discussed in the study is in treating glioblastoma (GBM), one of the most aggressive brain tumors. By adapting the treatment plan throughout the course of therapy, clinicians can account for changes in the tumor’s size and position. A prospective study involving a large number of GBM patients revealed substantial anatomical changes during treatment, underscoring the necessity for adaptive planning to maintain treatment accuracy and efficacy.
Additionally, the study explores the use of MRLs in stereotactic radiotherapy (SRT) for both intracranial and spinal tumors. The enhanced precision offered by MRL-guided SRT reduces morbidity compared to conventional methods. Feasibility studies have shown promising results for hippocampal avoidance whole brain radiotherapy (HA-WBRT), which aims to minimize cognitive side effects while effectively targeting tumors.
The study also details the capabilities of the two commercially available MRL systems: the ViewRay MRIdian and the Elekta Unity. These systems have shown significant improvements in dosimetry and treatment planning, demonstrating the potential to reduce radiation exposure to healthy tissues while maintaining effective tumor control.
The ongoing clinical trials highlighted in the study aim to validate these benefits further, with the hope of establishing MRLs as a standard tool in CNS tumor treatment. “Our goal is to provide evidence-based support for the widespread adoption of MRLs in clinical practice,” said Dr. Oliver.
Looking forward, the study suggests that integrating multiparametric MRI (mpMRI) and genomically guided radiotherapy could further enhance the precision and effectiveness of CNS tumor treatments. These advancements promise to tailor treatments to the unique biological characteristics of each patient’s tumor, potentially leading to better outcomes.
In summary, the integration of MRI with linear accelerators marks a significant advancement in CNS tumor treatment. Dr. Bryant, Dr. Oliver, and their colleagues are optimistic that as research continues and clinical trials confirm these findings, MRLs are poised to become a crucial tool in combating CNS malignancies.
Journal Reference
Bryant, John Michael, et al. “Treatment of Central Nervous System Tumors on Combination MR-Linear Accelerators: Review of Current Practice and Future Directions.” Cancers 2023, 15, 5200. DOI: https://doi.org/10.3390/cancers15215200
About the Authors
Dr. John Michael Bryant is the chief resident physician at the H. Lee Moffitt Cancer Center and Research Institute. Their research focuses on developing and translating advanced technologies to improve cancer patient outcomes, particularly in MRI-guided radiotherapy, deep neural networks for clinical outcomes prediction, and advanced nanomaterials for onco-theragnostic applications. In addition to their research, he is dedicated to enhancing research integration within clinical practice. As the co-founder and chair of the Canopy Cancer Collective Resident & Fellow Committee, they have coordinated collaborative research efforts across 14 leading cancer centers. As he transitions into attendinghood, he aims to continue leveraging advanced technologies to improve clinical outcomes and advance the field of radiation oncology.
Dr. Daniel Oliver is an Assistant Member in the Section of Neuro-Oncology and Supportive Care in the Moffitt Cancer Center Department of Radiation Oncology. Prior to medical school, Dr. Oliver served on the faculties of music (cello) at University of Alaska-Fairbanks and Emory University. He received his MD from Emory University School of Medicine and completed a Radiation Oncology Residency at Moffitt Cancer Center/University of South Florida. Dr. Oliver’s clinical interests are in the use of stereotactic and conventional radiation therapy to treat patients with primary and metastatic tumors of the brain and spine. His research interests focus on improving outcomes in early metastatic disease through a multidisciplinary treatment approach and advanced radiotherapy techniques.
Ajay Doniparthi is a 4th year medical student at the University of South Florida. He grew up in Brookfield, Wisconsin and received a Bachelor of Science degree in Biomedical Engineering from the University of Miami. He then completed a Master of Science with a concentration in Translational Biomedical Engineering at Northwestern University. He spent time as an engineering intern at Baxter completing R&D projects in the dialysis and disposable medical device divisions. Ajay is currently pursuing a career in vascular surgery. As his clinical journey begins, he is excited to explore new frontiers in medicine and ultimately translate these discoveries into tangible advancements that positively impact patient outcomes.
Dr. Stephen Rosenberg is Director of MRI Guided Radiotherapy and an Associate Member at Moffitt Cancer Center in the Department of Radiation Oncology. He grew up in Medford, New Jersey and graduated from Brown University with a Bachelor of Science in Biology. He earned a Master of Science in Clinical and Translational Research at Rutgers University in combination with his Medical Degree. During medical school, he was named a Howard Hughes Medical Institute Research Fellow. He went on to complete his medical internship at Memorial Sloan Kettering Cancer Center, where he was named the Suzanne Munson Intern of the Year. He completed his residency in radiation oncology at the University of Wisconsin where he also served as Chief Resident. Dr. Rosenberg’s clinical focus is the treatment of patients with thoracic malignancies. He is interested in combining radiation with immunomodulatory drugs and targeted therapies to improve outcomes. Dr. Rosenberg also pursues research with a special focus on MRI guided radiation. He is interested in utilizing radiomics and genomics as part of his research efforts. His work is part of the FORT (Future of Radiation Therapy) Departmental research program aimed at personalizing radiation therapy using novel approaches to improve local control of tumors and decrease side effects for patients.
