Neurological Use of Stereotactic Radiosurgery: Expanding Insights and Indications (Podcast)

Although stereotactic radiosurgery (SRS) is most commonly used to treat brain metastases, the technology is employed for a range of other indications, including facial pain disorders, vascular abnormalities such as arteriovenous malformation, and benign tumors affecting auditory nerves or balance centers. “There is a myriad of uses for benign and metastatic brain disease, not to mention our use of other stereotactic radiosurgery platforms for spine tumors,” says neurosurgeon Lilyana Angelov, MD, Director of Cleveland Clinic’s Gamma Knife Center.

Those wide-ranging indications are a focus of Dr. Angelov’s comments in the latest episode of Cleveland Clinic’s Neuro Pathways podcast, along with expert advice for use of SRS based on Cleveland Clinic’s nearly three decades of experience with the technology. In the episode, Dr. Angelov addresses a range of issues, including:

• How SRS differs from conventional radiation therapy, plus distinctions between SRS platforms for brain treatments versus spine and body treatments
• Minimally invasive and noninvasive methods for achieving the immobilization that’s crucial to SRS treatment
• The necessity of a multidisciplinary approach to SRS therapy
• Key differences between brain and spine radiosurgery
• Major factors that inform SRS treatment decisions, including number of lesions, patient age, neurocognitive concerns and overall disease burden
• Safety and toxicity profiles, and how they impact dosing strategies
• Pediatric applications of SRS
• Challenges in SRS therapy and future directions for the field

Click the podcast player above to listen to the 32-minute episode now or read on for an edited excerpt of its transcript. Check out more Neuro Pathways episodes at clevelandclinic.org/neuropodcast or wherever you get your podcasts.

This activity has been approved for AMA PRA Category 1 Credit™ and ANCC contact hours. After listening to the podcast, you can claim your credit here.

Excerpt from the podcast

Podcast host Glen Stevens, DO, PhD: You’ve been involved in some interesting research into ways of altering the pattern of administering stereotactic radiosurgery. Can you talk about fractionated or staged Gamma Knife^® therapy?

Lilyana Angelov, MD: When there is a large lesion, one Gamma Knife treatment may sometimes not durably address the brain tumor, in cases of tumors that are 2 centimeters or larger in size. In these cases, one approach is to give the radiosurgery for five consecutive days in the hope of delivering a dose-dense treatment. Alternately, what we have pioneered here at Cleveland Clinic is to do two-staged radiosurgery, which involves treating a patient in a given month and then giving a second treatment a month later, allowing them to receive their systemic therapy in between these treatments. Very often these tumors shrink even after the first treatment so that when you deliver the second treatment a month later, it is a smaller lesion and therefore has a smaller area of normal brain tissue around it. So, this approach can reduce toxicity while still delivering dose-dense treatment and allowing uninterrupted systemic treatments in the meantime.

This has changed the way we understand options for treatment delivery, and we are part of a multi-institutional trial of this approach involving Cleveland Clinic and a Japanese group that does very similar treatments. Our tumor control rates with staged treatment are 91% at one year and beyond, so this is a very gratifying, highly effective treatment with very acceptable side effects for the patient.