Introduction

1. Quality & Safety Considerationsin Stereotactic Radiosurgery and Stereotactic Body Radiation Therapy

2. Introduction • SRS is well established in cranial neoplasms achieving high local control rates and minimal toxicities. • SBRT is much more recent but results from multi-institutional trials have yielded similar results. • Selected early stage cancers • Oligometastases • Recurrent disease in previously radiated field

3. SBRT • High degree of anatomic targeting accuracy and reproducibility • High doses of precisely delivered radiation Minimize radiation related injury in adjacent normal tissue Maximize cell-killing effect

4. SBRT • Special attention and diligence is required for delivery of SBRT due to very small margin of error.

5. Errors in measurement of output factors affected 145 patients in Toulouse, France 2006 – 2007. • 31% 12-mth actuarial rate of trigeminal neuropathy in 32 acoustic neuroma patients overdosed.

7. Fundamental Elements of SRS and SBRT safety and quality • Immobilization, simulation, treatment planning, delivery and quality assurance is unique in each disease site.

8. Fundamental Elements of SRS and SBRT safety and quality • Multidisciplinary working environment fostering • Clear communication • Guards against inappropriate interruptions • Careful planning • Thorough risk assessment

9. Fundamental Elements of SRS and SBRT safety and quality • Thorough review of all resources including staffing levels and skills • Training of all personnel including: • Training in quality management • Safety practices • Program-specific education • Development of quality assurance processes that encompass all clinical and technical program aspects.

10. Fundamental Elements of SRS and SBRT safety and quality • Development of: • Checklists • Processes for documentation and reporting • Peer review • Regular review of processes and procedures • Updating of clinical guidelines and recommendations • Ongoing needs assessment • Continuous quality improvement

12. Personnel Considerations • Large commitment of resources required. • Coordinated efforts of properly trained individuals required to evaluate each patient and plan the treatment • Radiation oncologists, medical physicists, dosimetrists, radiation therapists • Other physicians can offer unique subspecialty expertise • Neurosurgeons, oncologic surgeons

13. Personnel Considerations • Initial training of personnel should be stepwise and via a structured education program. • Training on SBRT technologists including training by vendor(s) is an essential element.

14. Technical Considerations • Ablative doses of radiation coupled with small margins around CTVs require image guidance and motion management strategy. • Large numbers of non-opposing, often non-axial approaches through complex heterogeneities so doses need to be calculated accurately. • Isocenter placements are complex.

15. Technical Considerations • Simulation • Custom formed devices that cover a large extent of patient above and below the tumour for immobilization. • Anciliary localization and position monitoring technologies such as surface imaging techniques, implanted radiographic markers specific to tumour sites. • Image guidance strategies such as 4D computed tomography, soft tissue MRI imaging, metabolic information.

17. Acceptance and commissioning • Acceptance testing is performed in cooperation with equipment vendor to ensure equipment is operating within stated specifications and in compliance with regulatory requirements.

18. Acceptance and commissioning • Commissioning task includes measurement of radiation characteristics of the machine • Beam data acquisition involving small size of fields may be challenging and require appropriately small detectors. • Independent assessment of small field measurements may be essential and include comparison against published data, verifying data through completely independent set of measurements. • Independent verification of the absolute calibration, utilizing service by the Radiologic Physics Center is essential.

19. Acceptance and commissioning • Accurate calculation of dose and monitor units must be ensured. • Systematic comparison of calculation and measurement ranging from simple configurations to sophisticated beam arrangements. • Facilitated by site-specific anthropomorphic phantoms.

20. Acceptance and commissioning • Canadian Association of Provincial Cancer Agencies Stereotactic Radiosurgery – Radiotherapy Standards • ‘It is essential to recognize that commissioning SRS/T techniques involves more than just ensuring that the equipment itself works properly. The whole treatment chain, including the measuring, imaging modalities and treatment planning system must be tested in addition o the delivery unit and SRS/T tools.’

21. The Quality Assurance Program • Robust QA is crucial and must continuously evolve. • ‘The complexity, variation in individual practice patterns, and continued evolution of stereotactic-related technology can render a static, prescriptive QA paradihm insufficient over time.’

30. Recommendations for stakeholders • Vendors • Understand the needs and requirements of the clinicians, medical physicists and radiation therapists • Incorporate features and safeguards to assure efficacious and safe operation of their products. • Provide opportunities for specialized training, emphasizing clinical implementation and quality assurance (Not just equipment QA but process QA). • If more than one manufacturer involved, onus is on them to collaborate and ensure compatibility of their systems to ensure safe operation.

31. Recommendations for stakeholders • Professional organizations • Allocate resources to facilitate proper training in specialized procedures. • Specialized accreditation programs

32. Recommendations for stakeholders • Government agencies • Centralized registries for event reporting, such as those mandated by law in the United Kingdom, ensure appropriate transparency and provide effective mechanism for all stakeholders to learn from errors.

34. Summary • Team based approach • Appropriately trained and credentialed specialists. • Significant resources in personnel, specialized technology and implementation time required. • Thorough feasibility analysis needed. • Feasibility and planning discussions needed prior to undertaking new disease sites.

35. Summary • Acceptance and commissioning protocols and test must explore every aspect of individual and integrated systems. • Comprehensive QA program encompassing all clinical, technical and patient specific treatment aspects. • All stakeholders must demonstrate clear commitment and work closely together to ensure highest level of patient safety and efficacy in SBRT.