Gamma Knife Radiosurgery A Team Approach to Treating Patients George Bovis, MD Patrick Sweeney, MD Jagan Venkatesan, MS Matt White, MS Illinois Gamma Knife Center Elk Grove Village, IL Disclosures Shareholders in IGKC Purpose Define Stereotactic Radiosurgery Discuss specifics of Gamma Knife radiosurgery- 4c/Perfexion Review clinical indications and our experience at the Illinois Gamma Knife Center Discuss ‘competing’ indications for GKRS (Proton Beam Therapy) Stereotactic Radiosurgery SINGLE FRACTION High dose Small volume High conformality Excludes sensitive structures Exclusively CRANIAL Exclusively FRAME- BASED OLD SCHOOL DEFINITION Stereotactic Radiation: 2014 SABR (stereotactic ablative body RT) SBRT (stereotactic body radiotherapy SRT (stereotactic radiotherapy) SRS (stereotactic radiosurgery) 1980s 1990s 2000s 2010s Radiation 2-d 3-d CRT IMRT IGRT Therapy Stereotactic Frame based Frame based Radiosurgery Relocatable frames Gamma U series Exclusively CRANIAL Frameless CRANIAL, SPINE, LUNG, PROSTATE, LIVER, PANCREAS Linac based We are all radiosurgeons now! Varian True Beam Gamma Knife Lars Leksell Swedish Neurosurgeon First developed Gamma Knife in 1968 Was a neurosurgical device that used radiation Stereotaxy Implies defining a point in space relative to a Cartesian coordinate system: FRAME There are surgical instruments that use stereotaxis to locate targets in the body In radiation therapy simulation and treatment we also use stereotaxis but it is relative to a CT-generated image: PATIENT Gamma Knife Radiosurgery Only exclusively frame-based intracranial system that is still used today All other radiosurgery systems are capable of frameless and extracranial indications The Leksell Patient frame vs The Leksell Frame placement and Coordinate System History 1951 Lars Leksell Large Number of Converging Beams of Ionizing Radiation Creating Small Volumes of Necrosis at Stereotactically Targeted Region of Brain History LINAC Gamma Radiation Protons Stereotaxis Target Visualization ◦ X-Ray ◦ Pneuomoencephalography ◦ Angiography History Cobalt-60 Unit 1967 Gamma Knife ◦ 179 Co-60 Sources ◦ Sophiahemmet Hospital 1974 Gamma Knife U – Unit ◦ 201 Co-60 Sources ◦ Karolinska Hospital History 1970-1987 CT MRI Improved Stereotaxis with Computers Better Understanding of Radiobiology History 1968 – 1982 Treated 762 patients Trigeminal Neuralgia Acoustic Neuroma AVM Pituitary Adenoma Meningioma Metastasis Functional History 1987 - First Gamma Knife installed in U.S., at the University of Pittsburgh ◦ Lunsford 1989 Mayo Clinic ◦ Coffey Formalized And Methodical Study of GK SRS Publication of Huge Body of Scientific Work Evolution Cobalt-60 201 Sources Leksell Frame Trunnion Mode Collimator Size ◦ 4 mm, 8 mm, 14 mm, 18 mm ◦ Manually Mounted Evolution Computer Based Workstations Planning Software 3D Dosimetry and Anatomical Imaging Improved Conformality and Selectivity Robotic Automatic Positioning System (APS) Evolution Evolution 2002 – Elekta ◦ Next Generation of GK 2 Principles Would Not Change ◦ Converging Beams ◦ Frame Goals For New Machine ◦ Best Dosimetry ◦ Best Radiation Protection ◦ Unlimited Cranial Reach ◦ Fully Robotic and Automated ◦ Outstanding Patient Comfort ◦ Ease of Treatment For Pt and Staff ◦ Maintain Relevance of Cumulative Worldwide Literature The Anatomy of the Gamma Knife 4C 1 - Couch Support 4 - Shielding Door 7 - Shielding 2 - Patient Couch 5 - Beam Channel 8 - Helmet In Treatment 3 - Helmet 6 - Cobalt-60 Sources Position 9 - Sliding Cradle The Perfexion The Perfexion System The Perfexion Couch PerfeXion Shielding Not Good Protection or Shielding PerfeXion Jean Regis, et al “Radiosurgery With The World’s First Fully Robotized Leksell Gamma Knife PerfeXion in Clinical Use: A 200- Patient Prospective, Randomized, Controlled Comparison With The GK 4C”. Neurosurgery 64 (2), Feb 2009 33 % Reduction in Tx Time 30 % Reduction in Shots Used Nearly All Cases Single Run No Collisions 8.2 X Less XRT To Vertex 13 X Less XRT To Sternum 15 X Less XRT To Gonads PerfeXion STILL A Growth Area in Neurosurgery WBRT vs SRS/GK for Multiple Mets (# ?) ◦ Kalkanis, S, et al. Evidence-based clinical practice parameter guidelines for the treatment of patiens with metastatic brain tumors. J Neurooncology (2010) 96: 7-10. ◦ Robinson, P, et al. Methodology used to develop the AANS/CNS management of brain metastases evidence- based clinical practice parameter guidelines. J Neurooncology (2010) 96: 11-16. ◦ Gaspar, L, et al. The whole brain radiation therapy in the management of newly diagnosed brain metastases: a systematic review and evidence-based clinical practice guideline. J Neurooncology (2010) 96: 17-32. ◦ Kalkanis, S, et al. The role of surgical resection in the management of newly diagnosed brain metastases: a systematic review and evidence-based clinical practice guideline. J Neurooncology (2010) 96: 33-43. Epilepsy (MTLE) ◦ NIH Study – Radiosurgery or Open Surgery for Epilepsy (ROSE), PI Nicholas Barbaro Cluster Headache ◦ Kano, K, et al. Stereotactic radiosurgery for intractable cluster headache: an initial report from the North American Gamma Knife Consortium. J Neurosurgery. April 30, 2010 DBS vs SRS/GK for OCD, Depression PerfeXion “Gamma Knife Comes With Patients” Direct Patient Requests “Gold Standard” Exercise In Efficiency More Options For Your Patients “Complete Brain Surgeon” “A Pinpoint Beam Strays Invisibly, Harming Instead of Healing” By Walt Bogdanich and Kristina Rebelo December 28, 2010 http://www.nytimes.com/2010/12/29/he alth/29radiation.html?_r=1 PerfeXion Illinois Gamma Knife Center 2005 ◦ 2 Neurosurgeons ◦ 2 Radiation Oncologists 2014 ◦ 8 Neurosurgeons ◦ 4 Radiation Oncologists Gamma Knife: Dosimetry SHOTS: spheres of dose ‘Pack’ shots into irregular shaped targets MRI/CT/Angio Rarely contour Never add a margin Prescribe to 50% isodose line Not concerned about inhomogeneity in the target ◦ MD/PD: maximum dose/Rx dose Very concerned about Cleveland Clinic conformality: ◦ CI: volume of Rx isodose/ volume of target volume at Rx isodose level Linac-based SRS Circular collimators mMLC Dynamic arcs IMRT � Contour � Small margin � Homogenous dose distribution Gamma Knife Radiosurgery Target Isodose lines Gamma: Knife: A Team Approach Gamma Knife Process Outpatient One day Imaging Planning Treatment Treat to 7 pts/day Stand-alone clinic: plan and treat patients/ consults/follow-ups The four basic steps on Tx Day 1. Head Frame Placement 2. Imagin g 3. Treatment 4. The planning Treatment Gamma Knife Advantages A Neurosurgeon’s perspective Lower Risks Compared to Open Surgery Better Tolerared than Open Surgery Outpatient No Recovery Time Return to work in 1 day Very Accurate and Precise Treatment for previously inoperable brain tumors. Simple Procedure (when performed correctly) “A Fool With A Tool, Is Still a Fool” Pain-Free Gamma Knife treatment usually more cost-effective than Open Surgery. Clinical Indications Brain Metastasis Meningiomas Vestibular Schwannomas Trigeminal Neuralgia Arteriovenous Malformations Gliomas Skull-Base Tumors Pituitary Tumors Other functional disorders ◦ OCD, Epilepsy, Tremors Our Experience… Brain Metastasis Most Common Indication Ideal targets ◦ Round ◦ Non-infiltrating ◦ Easily Defined Most common Tumor Types ◦ Breast ◦ Lung ◦ Melanoma ◦ Renal ◦ Colon Brain Metastasis Whole Brain RT becoming more controversial ◦ Especially in solitary metastasis What is the maximum number of metastasis to treat? 5…10…15….. 53 yo female with multiple brain metastasis. Refused WBRT Mets Plan 1 (6 Months) Mets Plan 2 (3 & 6 Months) Arteriovenous Malformations (AVM) Abnormal collection of blood vessels bypassing the capillary system Can occur in any part of the body Symptoms are headache/seizures Arteriovenous Malformations (AVM) New Data: Lancet, 383: 614- Natural History 621, 2014 ◦ 2-4 % Rate of Rupture per Year ◦ 10-20 % Mortality per Rupture ARUBA TRIAL (A randomised trial ◦ 30-50 % Major Neurological of unruptured brain AVM) ◦ Randomized patients with Morbidity per Rupture unruptured AVMs to medical mgmt alone versus some Likelihood of rupture in intervention (surgery, lifetime embolization, SRS, combinations) ◦ Medical management alone is 105 – Age in Years superior to interventional therapy in the prevention of death or stroke ◦ 10% in medical mgmt had death or stroke vs. 30.7% in the intervention arm AVM visualized on MRI AVM with Angio & MRI 3D Model of the AVM AVM Case 1 Presentation @ Initial Consult 2 Years Post Gamma Knife AVM Case 2 Presentation 4 Years Post GK AVM Case 3 Presentation 1 Year Post GK Meningioma Tumors that arise from the meninges 90-95% are benign Many are asymptomatic and require no intervention Surgery is primary treatment SRS is reasonable for small, unresectable meningiomas Meningioma Plan (1.5 Years) Trigeminal Neuralgia (TN) Lancinating Pain in distribution of CN V Unilateral Relieved by medication Normal exam ‘triggers’ Treatments: MVD, PSR, GKRS TN Plan Vestibular Schwannoma Acoustic neuroma Benign tumor of the vestibulochochlear nerve (CN 8) 3000 per year in US Treatment options: ◦ observation ◦ Surgery ◦ SRS (GKRS) ◦ fSRT ◦ conventional RT SRS has become prime treatment for these tumors Microsurgery Results Best Current Results Published By High Volume Surgeons (Tumors < 3 cm) ◦ High Rate of Complete Rsxn ◦ Low Recurrence Rate ◦ High Rate of Normal / Near Normal CN 7 Function 85% ◦ Hearing Preservation ??? Depends on approach and