Slide 1 ___________________________________ Stereotactic RT in Early Stage Lung Cancer Is the Evidence Compelling??? ___________________________________ Walter J Curran, Jr, MD ___________________________________ Executive Director Winship Cancer Institute of Emory University Group Chairman ___________________________________ Radiation Therapy Oncology Group ___________________________________ ___________________________________ ___________________________________ Slide 2 ___________________________________ Stereotactic Involving (being, utilizing, or used) a surgical ___________________________________ technique for precisely directing the tip of a delicate instrument (as a needle) or beam of radiation in three planes (?) using ___________________________________ coordinates provided by medical imaging in order to reach a specific locus in the body (as a tumor in the brain, lung or liver) ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 3 ___________________________________ ___________________________________ What enabled the Stereotactic Body Radiation Therapy (SBRT) ? ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________
Slide 4 ___________________________________ David Jablons’ Mentors in Thoracic Surgery ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 5 ___________________________________ David Jablons’ Mentors in Thoracic Surgery ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 6 ___________________________________ David Jablons’ Mentors in Thoracic Surgery ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________
Slide 7 ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 8 ___________________________________ Technology Enabling SBRT ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 9 ___________________________________ What is SBRT? ___________________________________ • Potentially highly effective ___________________________________ • Potentially extremely dangerous ___________________________________ ___________________________________ ___________________________________ ___________________________________
Slide 10 ___________________________________ RT Fractionation Options ___________________________________ • Conventionally Fractionated RT - small daily doses - go to very high cumulative doses - tolerable for most normal tissues • Hypofractionated RT ___________________________________ - larger daily doses (3-8 Gy) - used mostly for palliation • Ablative RT (Stereotactic) - very high daily doses (8-20 Gy) ___________________________________ - overwhelm tumor repair - causes “late” effects that may be intolerable ___________________________________ ___________________________________ ___________________________________ Slide 11 ___________________________________ Hypofractionation Benefits • Reduce number of trips ___________________________________ – Increases convenience for patients – Decreased costs to system • Hospital staffing and equipment Payors ___________________________________ • Biological – Radiation at a specified dose is more tumorcidal if ___________________________________ given in fewer “fractions”/High Dose ___________________________________ ___________________________________ ___________________________________ Slide 12 ___________________________________ Survey: 9 out of 10 Tumor Cells Prefer Conventional Fractionation ___________________________________ 10 0 multiple 2 Gy fractions Survival ___________________________________ 10 -1 single fraction ___________________________________ 10 -2 2 4 6 8 Dose (Gy) ___________________________________ ___________________________________ ___________________________________
Slide 13 ___________________________________ Ablative Treatments (Stereotactic) Must Exclude Normal Tissue ___________________________________ • Requirements for ablative hypofractionation: – Abandon prophylactic treatment – Account for organ motion ___________________________________ – Achieve sharper dose fall-off gradients to normal tissue (mimic radiosurgery) • These requirements need advanced technology ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 14 ___________________________________ Ablative Treatments (Stereotactic) Must Exclude Normal Tissue ___________________________________ • Requirements for ablative hypofractionation: – Abandon prophylactic treatment – Account for organ motion ___________________________________ – Achieve sharper dose fall-off gradients to normal tissue (mimic radiosurgery) • These requirements need advanced technology ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 15 ___________________________________ Phase I Dose Response for Local Control ___________________________________ 100 Local Control (%) 80 17 Month 60 ___________________________________ 40 20 0 0 20 40 60 80 ___________________________________ Total Dose (Gy) in 3 Fractions ___________________________________ ___________________________________ ___________________________________
Slide 16 ___________________________________ :RTOG 0236 Robert Timmerman, MD; Rebecca Paulus, BS; James Galvin, PhD; Jeffrey Michalski, MD; William Straube, ___________________________________ PhD; Jeffrey Bradley, MD; Achilles Fakiris, MD; Andrea Bezjak, MD; Gregory Videtic, MD;David Johnstone, MD; Jack Fowler, PhD; Elizabeth Gore, MD; Hak Choy, MD • First North American cooperative group trial testing SBRT ___________________________________ • Non-small cell lung cancer - biopsy proven • T1, T2 ( 5 cm) and T3 (chest wall only, 5 cm), N0, M0 ___________________________________ • Medical problems precluding surgery (e.g. emphysema, heart disease, diabetes) • No other planned therapy ___________________________________ ___________________________________ ___________________________________ Slide 17 ___________________________________ Stereotactic Body Radiation Therapy Stereotactic Body Radiation Therapy ___________________________________ Pulmonary Vein Bronchus Lu ng Esophagus Chestwall ___________________________________ Cord Skin ___________________________________ RTOG 0236: 20 Gy X 3 60 Gy in 3 Treatments ___________________________________ ___________________________________ ___________________________________ Slide 18 ___________________________________ RTOG 0236: Local Control (JAMA 2010) 100 100 / / / / // / / / / // / / / // / / / / // / / /// / / / ___________________________________ 75 75 Local Control (%) 36 month local control = 98% (CI: 84-100%) 50 50 ___________________________________ 1 failure within PTV, 0 within 1 cm of PTV 25 25 Fail: 1 Total: 55 0 0 0 0 6 6 12 12 18 18 24 24 30 30 36 36 ___________________________________ Patients Months after Start of SBRT at Risk 55 54 47 46 39 34 23 ___________________________________ ___________________________________ ___________________________________
Slide 19 ___________________________________ RTOG: 0236 Disseminated Recurrence • 6 patients (11%) disseminated within 1 year of Rx 100 100 ___________________________________ Disseminated Recurrence (%) Fail: 11 75 75 Total: 55 50 50 ___________________________________ 36 month disseminated recurrence = 22% (CI: 12-38%) 25 25 // / / / / / / // / / / / / / / / / / / / / / 0 0 ___________________________________ 0 0 6 6 12 12 18 18 24 24 30 30 36 36 Months after Start of SBRT Patients at Risk 55 51 44 43 38 33 21 Timmerman: JAMA 2010 ___________________________________ ___________________________________ ___________________________________ Slide 20 ___________________________________ RTOG 0236 : Best Observed Response n=55 ___________________________________ Complete Response 23 (42%) Partial Response 22 (40%) ___________________________________ Stable 9 (16%) Not evaluated 1 (2%) ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 21 ___________________________________ Post-SBRT Treatment Lung Reaction ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________
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