Highlighting Emerging Technologies in CNS Radiation Oncology

At the 2026 American College of Radiation Oncology (ACRO) Summit, Charlotte Ivy Rivers, MD, a radiation oncologist at the Medical University of South Carolina, served as the moderator for the Central Nervous System (CNS) traditional session. The session highlighted critical developments in the management of rare brain tumors, the integration of molecular biomarkers, and the expanding role of functional radiosurgery in treating benign conditions.

In this interview, Rivers explored the anticipated results of ongoing NRG trials, the multidisciplinary approach to patient care, and the system-level barriers affecting access to specialized neuro-oncology services.

CancerNetwork: Why is CNS such an important topic to discuss at a forum like ACRO?

Rivers: CNS is a vital area of our field. I perform a lot of radiosurgeries, and I believe the CNS space is sometimes underrepresented in clinical trials because many patients have rare diseases. It remains important to find effective options for patients with rare tumors.

What are your expectations for the presentation from Vinai Gondi, MD, on advances in meningioma radiotherapy?

I expect it to be an interesting and relevant talk.¹ We treat many meningiomas at my institution. Grade II and III meningiomas are rare, and there is a significant gray area regarding their management. I hope the presentation provides practical advice and upcoming data for treating atypical meningiomas.

In the same vein, is there any specific research you are looking out for in the meningioma space?

We are all looking forward to the results of the [phase 3 NRG-NB003 trial (NCT03180268)] investigating adjuvant radiation vs observation for grade II meningiomas. Many institutions also use radiosurgery for meningiomas. There are limited data for that, so it [remains] an area of significant interest.

What are your thoughts on the presentation from Evan Thomas, MD, PhD, on functional radiosurgery?

In our field, in general, a lot of what we’re doing is moving toward treating more benign conditions.² It is something we do at our institution, as well as treating trigeminal neuralgia. But there are other indications for functional radiosurgery, such as essential tremors and certain psychiatric disorders.

Are there trials in CNS cancers that you are waiting to see the results of?

We want to know the results of several NRG trials—I had mentioned the meningioma trial—and there’s also an ongoing trial looking at fractionation schemes for brain metastases. These could potentially be practice changing. In the glioblastoma space, there are newer trials, specifically GammaTile trials, that are beginning to open.

Generally, what clinical or radiographic factors influence your decisions regarding early vs delayed radiation in CNS tumors?

It depends on the tumor type. For meningiomas, we look for residual disease and whether the tumor is close to critical structures. Those are important on imaging. For other tumors, we assess the location, size, and the patient’s symptoms to determine if radiation is necessary. These factors also help us decide between fractionated radiation or radiosurgery.

How are advancing imaging and emerging biomarkers influencing selection, targeting, and assessment in CNS radiation?

These factors are influencing many aspects of care. For biomarkers, in particular, the whole classification for primary gliomas changed with the [2021] World Health Organization criteria.³ That’s changed how we diagnose primary gliomas and which drugs patients are eligible for. In meningiomas, there is growth in using molecular features to predict tumor behavior and determine the need for radiation or targeted therapies. Regarding imaging, we are using more functional imaging, such as DOTATATE PET scans, to guide treatment. Techniques like contrast clearance analysis also help us distinguish between tumors and radiation necrosis. Those are things that have been changing a lot, even in the past 5 years.

How can radiation oncologists best collaborate with other specialties, such as neurosurgery or neuro-oncology, to select patients and define goals?

A multidisciplinary team is essential, especially for patients with rare tumors. Tumor boards are very important. At our institution, we see patients on the same day with neurosurgery, radiation oncology, and neuro-oncology to ensure everyone is on the same page. If a patient has an option of surgery vs radiation or combination [therapy], it is important the patient meet with both doctors to decide what will give them the outcome they are looking for.

What system-level barriers limit access for patients requiring advanced CNS radiation?

Location is a huge barrier, as far as access to high-quality neurosurgery and neuro-oncology. In South Carolina, our institution is currently the only one with neuro-oncology. This is a limitation for patients coming from community centers. [Another barrier is] having doctors available at certain locations; sometimes, even large centers do not have all those specialties available.

Since your institution is the only one in the state with neuro-oncology, how does that impact how you treat patients who must travel long distances?

We have 3 neuro-oncologists, and many people come to us for second opinions. Telehealth has helped us reach patients in remote places to provide access to opinions regarding their care. We also work closely with community radiation oncologists. If we have a patient with a rare tumor, we provide certain recommendations. We also maintain relationships with other physicians across the state so that we can help in that way. Our neuro-oncology team also works with local oncologists to prescribe chemotherapy or other recommended treatments.

References

1. Gondi V. Slow and strategic wins the race: radiotherapy advances for meningioma. Presented at the 2026 American College of Radiation Oncology Summit; Orlando, FL. February 4-6, 2026.
2. Thomas E. A functional radiosurgery renaissance: lesional therapy strikes back. Presented at the 2026 American College of Radiation Oncology Summit; Orlando, FL. February 4-6, 2026.
3. Fernandes RT, Teixeira GR, Mamere EC, Bandeira GA, Mamere AE. The 2021 World Health Organization classification of gliomas: an imaging approach. Radiol Bras. 2023 ;56(3):157-161. doi:10.1590/0100-3984.2022.0089-en