We asked Mark De Ridder, MD, PhD, about the challenges involved in radiotherapy, how hospitals can get the most out of their technology, and why he thinks peer review is important to ensure the best possible patient care.
Stereotactic radiosurgery and stereotactic body radiotherapy are essential treatment options for oncology patients. For Prof. De Ridder, ensuring the best outcomes in radiation treatment means advocating for advanced technologies and making sure clinical teams follow the highest possible standards.
Prof. De Ridder, an experienced radiation oncologist, is a long-time Brainlab customer and has been the head of the Radiotherapy Department and Supportive Care Department at UZ Brussel since 2010. He and his team treat about 1,950 oncology patients per year with a variety of indications.
Given your specialty, could you briefly explain what stereotactic radiosurgery and stereotactic body radiotherapy are?
Stereotactic radiosurgery (SRS) is a highly precise treatment method used to target malignant and benign brain lesions in a single session. Over the past decade, the approach to treat brain metastases has shifted from whole brain radiotherapy to SRS, which now accounts for over 90% of SRS indications due to the high incidence of brain metastases in cancer patients. SRS is also frequently employed for benign conditions such as vestibular schwannomas, trigeminal neuralgia, pituitary adenomas, meningiomas and arteriovenous malformations.
Stereotactic body radiotherapy (SBRT) builds on the expertise gained from SRS and applies it to extracranial conditions, targeting lesions in areas such as the spine, lungs, and liver. Treating lung and liver lesions with SBRT can be particularly challenging due to the movement of these lesions during respiration. The delivery of SBRT can be performed in a single session as well as in a hypofractionated way.
What do you find to be the challenges associated with delivering SRS and SBRT?
In Stereotactic radiosurgery (SRS), the primary technical challenge is the precise delivery of the dose to the exact target area. Since the treatment is administered in a single fraction, there is absolutely no margin for error. When treating multiple lesions in a single session, it is crucial to ensure consistent patient alignment to maintain accuracy. Another critical aspect of delivery is maintaining this high level of precision throughout the entire dose administration.
Anatomical challenges may arise depending on the lesion's location, making it difficult to achieve and maintain the sharp dose gradients required during treatment. In spinal radiosurgery, accuracy is especially vital because the spine is always in close proximity to the target area. Any reduction in accuracy could necessitate larger safety margins, potentially overlapping with the spinal cord and limiting the ability to administer a high dose.
For SBRT of lung and liver lesions, there is also the need to cope with motion. Different motion-encompassing techniques exist to treat those lesions accurately.
How can medical practices and hospitals seek to overcome these challenges?
Technology plays a crucial role in addressing the critical challenges mentioned. The capabilities of each hospital depend on the specific equipment they have installed, which may come with certain limitations. It's essential to recognize and integrate these limitations into daily practice. This is why collaboration between physicists and medical doctors is so important to fully understand the challenges and boundaries of the technology they use.
For lung SBRT for instance, some centers use motion encompassing techniques. They create an internal target volume based on 4D-CT and/ or PET scans. The positioning is then preferentially checked by a 4D-CBCT. Other centers use gating or tracking based on the tumor, fiducial markers or anatomical surrogates. Gating is usually combined with a breath hold technique. Each center should establish its treatment strategy based on equipment and local expertise.
Can you tell us why peer review dedicated to stereotactic radiosurgery and stereotactic body radiation therapy is important for patients and clinical teams?
SRS and SBRT are challenging treatments regarding the above-described individual treatment choices, their technical demands and patient selection. It is necessary to implement multidisciplinary, dedicated care paths covering clinical and physical issues and quality assurance. Peer review is essential for the control and continuous improvement of these protocols. For several years, I’ve seen the positive impact of peer reviews from the Novalis Expert Group on the quality of care for both less and more experienced radiosurgical centers.
You mentioned the Novalis Expert Group. Can you describe your role as a Novalis Certified Expert and the work you do with other group members? Why is the program important for providers?
First, our group of experts creates and updates the standards for SRS and SBRT. The multidisciplinary mix of neurosurgeons, medical physicists and radiation oncologists ensures a holistic view of the different care paths. Second, we review the reports of the auditors to ensure their quality and homogeneity. Third, we provide advice to the centers before, during and after accreditation.
The Novalis Certified Program is important for healthcare providers to introduce and maintain the high-quality standards that are required for a successful and safe radiosurgery program. We work closely together as a group of experts with regular meetings and email conversations. Tim Solberg is the Papa Smurf of our expert group. His experience and view on the field greatly contribute to the quality of our work.
What are the advantages that Novalis Certified facilities have compared to non-certified facilities?
The advantage of being certified is the fact that you receive an external audit by colleague experts who provide valuable feedback on your SRS/SBRT program. Given the complexity and constant evolution of these technologies, such audits are crucial for ensuring that you deliver the highest possible quality of care to your patients. Besides the patients, accreditation is an important asset for the centers concerning knowledge, staff training, reputation and patient accrual. Who wants to be treated in a non-certified center?
Is Novalis Certified linked to the existing technology?
The Novalis certification evaluates a hospital's SRS/SBRT program independently of the specific technology used. What matters most is demonstrating that the program meets a high standard in terms of organization, infrastructure, procedures, staffing, technology and quality assurance.
How do patients benefit from the Novalis Certified Program?
This certification enhances and promotes both treatment quality and patient safety, which of course is beneficial for our patients. In addition, patients can choose a center based on its certification and be sure that they will benefit from a high standard of care.
What has changed in your department since you’ve become Novalis Certified?
Our department has a long history of radiosurgery and quality assurance. As such, it did not intrinsically improve our techniques or change the philosophy of our key opinion leaders. But the accreditation program created a broad awareness of the dedicated radiosurgery care paths and quality standards within our entire team of senior and junior radiation oncologists, physicists and RTTs. Moreover, it pushes us to continuously improve and update our procedures. It facilitated the creation of a dedicated multidisciplinary quality team within our department.