Jeffrey A. Bogart M.D. Upstate Medical University November 15, 2013 Proton Therapy for Lung Cancer Therapeutic Advance or The Straw that Broke the U.S. Medical System’s Back? Jeffrey A. Bogart M.D. Upstate Medical University November 15, 2013
Disclosures Chair, Alliance Radiation Oncology Committee Stipend Upstate Medical University recently signed a MOU with Advanced Oncotherapy PLC to proceed with developing a proton therapy center
Learning Objectives Review current state of the art (radio)therapy for locally advanced NSCLC Describe available evidence for proton therapy in treatment of early stage NSCLC Discuss opportunities and challenges in treatment of locally advanced NSCLC with proton therapy
Background Stage III NSCLC Primary RT: Local tumor control ~ 15% ChemoRT: In-field failure 33%+ (RTOG 9410) Hypothesis: Modulating RT delivery will improve local control and ultimately survival
RT Practice Standards The new millennium … IMRT, IGRT, 4D planning now routine Should shift therapeutic index But ..no change in the radiotherapy dose schedule for locally advanced NSCLC since the 1970’s 6000 cGy / 6 weeks
3D Dose Escalation Dose Escalation : Conventional Fractionation 74 Gy in 2 Gy fractions was feasible with concurrent weekly paclitaxel and carboplatin Trial Phase n Med survival RTOG 9410 (63Gy) III 200 17 months UNC 9603 I/II 62 24 mo CALGB 30105 II 43 NCCTG 0028 I 13 37 mo RTOG 0117 44 (stage 3) 21.6 mo
Concurrent Chemotherapy: RTOG 0617 STRATIFY RT Technique 3D-CRT IMRT Zubrod 1 PET Staging No Yes Histology Squamous Non-Squamous RANDOMIZE Concurrent Treatment Consolidation Treatment Arm A Concurrent chemotherapy* RT to 60 Gy, 5 x per wk for 6 wks Consolidation chemotherapy* Arm B RT to 74 Gy, 5 x per wk for 7.5 wks Arm C Concurrent chemotherapy* and Cetuximab Consolidation chemotherapy* and Cetuximab Arm D Concurrent chemotherapy* and Cetuximab Bradley, ASCO 2013
Well conducted trial allowing state of the art technology and good QA RTOG 0617 Local Relapse also increased (37%) on 74 Gy arm Well conducted trial allowing state of the art technology and good QA Arm Median OS Severe Esophagitis Grade 5 Toxicity 60 Gy 28.7 months 7% 2 patients 74 Gy 19.5 months 21% 10 patients Bradley, ASCO 2013
Locally Advanced NSCLC Conventional Radiotherapy Conventional RT Traditional “protracted” dose escalation is a flawed and failed strategy in combined modality therapy Locally Advanced NSCLC Protracted Conventional Radiotherapy
What Now? Alternate Radiotherapy Schedules
Hyperfractionation RTOG 9410: 1.2 Gy BID to 69.6 Gy Lower dose per fx reduced toxicity? Con.STD 63Gy Con. HFX 69.6 Gy Median survival 17 mo 15.6 5-year survival 16% 13% Acute Esop. Tox. 22% 45% Late Pulm. Tox. 19% Curran, JNCI 2011 11
Higher dose per fraction Hypofractionation Higher dose per fraction Safe with advanced technology? Trial RT Regimen Chemo Survival Late Toxicity EORTC (1999-03) 2.75 Gy x 24 (66 Gy) Cisplatin 6 mg/m2 daily 3 yr: 33% 4 % Esophageal 18 % Pulmonary SOCCAR 2.75 Gy x 20 (55 Gy) Cisplatin/ vinorelbine 27.6 mo median “acceptable” Stricture? KROG (2003-05) 2.4 Gy x 25 (60 Gy) Paclitaxel/ carboplatin 28.1 mo median 2 hemoptysis 3 stricture 12
Active Photon Studies Stage III ChemoRT CALGB 31102 Phase I : Maintain Total Dose at 60Gy Increase dose/fraction - reduce treatment time Next cohort : 3 Gy x 20 Fx over 4 weeks RTOG 1106 Random phase II : individualized adaptive RT using during-treatment FDG-PET/CT Doses as high as 85 Gy in 30 fx given 13
What Else? Charged particle therapy
Proton Therapy + Charged Particle Physical properties differ from photons Potential for better protection of normal structures But treatment planning relatively immature c/w photons Passive Scattering (~ 3D) : majority of published studies IMPT (~ IMRT) – dose painting Biologic efficacy similar
Precise energy placement
Pediatric Malignancies Reduced dose to normal tissue limit impact on growth reduce secondary malignancy risk
Proton Therapy Cost : $25,000,000 to > $200,000,000
Building Boom of Proton Beam Centers Flares Up in Washington and Baltimore Cancer Letter : Oct 25, 2013 “About 100,000 people have been treated with proton beam radiation, and about 85 percent of them received it for prostate cancer “ - Level 1 evidence supporting protons over photons does not exist Undue severe toxicity has not ben reported
Early Lung Cancer
Photon SBRT
“Protons generate larger high-dose regions than photons because of range uncertainties. This can result in nearby healthy organs (e.g., chest wall) receiving close to the prescription dose, at least when two to three beams are used, such as in our study” Seco et al Red Journal 2012
reduced (low dose) lung , heart , esophagus dose with proton SBRT Georg Radioth Onc 2008
Photon SBRT RTOG 0236 60 Gy / 3 fx (peripheral tumors only) 97% in-field local control Timmerman JAMA 2010
Proton Therapy Early lung Cancer Loma Linda (2013) 111 patients, T1+ T2 tumors 4-year OS dose dependent :18% (50 Gy), 32% (60 Gy), 51%(70 Gy) Local Control 96% for Peripheral T1 if 60 Gy + Clinical radiation pneumonitis was not found to be a significant complication. “Meta-analysis” (2010) “Five-year overall survival similar with SBRT (42%), proton therapy (40%) and carbon-iontherapy (42%). However, caution is warranted due to the limited number of patients and limited length of follow-up of the particle studies” Bush et al Red Journal 2013 Grutters et al Radioth Oncol 2010
Proton Therapy Locally Advanced Lung Cancer Photon IMRT
Proton Therapy Locally Advanced Lung Cancer V20 Lung = Volume of Lung Receiving 20 Gy
Proton Therapy Locally Advanced NSCLC Reduced low dose exposure to lungs and medium / low dose to heart V20, V 5……TOG 0617 Chang et al Red Journal 2006
Stage III NSCLC Does what we see on paper (or the computer screen) translate into real life?
Proton Therapy Locally Advanced Lung Cancer Complicating Factors Depth of penetration /Bragg peak varies significantly based on the density of tissues Range uncertainty (extra margin of safety) Tumor Motion introduces further uncertainty
PT + Chemotherapy Stage III NSCLC Phase II (MD Anderson, n = 44) 74 Gy(RBE) + weekly carboplatin (AUC 2) and paclitaxel (50 mg/m2 ) FDG-PET/CT staged passively scattered proton Cone beam CT not available Median Survival 29.4 months (19.7 month median FU) Local relapse 20.5 % , 9.3 % nodal relapse Toxicity 11.4% grade 3 dermatitis , 11.4% grade 3 esophagitis 1 grade 3 pneumonitis and 1 pulmonary/pleural fistula Chang et al Cancer 2011
PT + Chemotherapy Stage III NSCLC University of Florida (n = 19) Median 74 Gy(RBE) + chemotherapy Median 16 month FU Toxicity 1 acute grade 3 and 1 late grade 3 non-hematologic toxicity 1 documented in-field progression Hoppe et al Lung Cancer 2012
Locally Advanced Primary RT Re-irradiation(n= 33) PORT/Mediastinal RT Poor DFS/OS with PT alone Re-irradiation(n= 33) MD Anderson Repeat RT to 66 Gy (median 3 year interval) 54% 1-yr local control, 9/33 in-field relapse Toxicity Gr 3 : 9% Esophageal, 21 % pulmonary Gr 4 : 3% Esophageal, 7 % pulmonary PORT/Mediastinal RT Better Protect Heart and Surrounding Lung c/w photon McAvoy et al Radiother Oncol 2013
RTOG 1308: Phase III Randomized Trial Comparing Overall Survival after Photon vs Proton Radiochemotherapy for Stage II-IIIB NSCLC Stratify Stage 1.II 2.IIIA 3.IIIB GTV 1.<= 130 cc 2.>130 cc Histology 1.Squamous 2.Non-Squamous Neoadjuvant Chemotherapy Yes No RANDOMIZATION Arm 1 Photon: Highest achievable dose between 60-70 Gy at 2 Gy, once daily plus platinum-based doublet chemotherapy Arms 1 and 2: Consolidation Chemotherapy x 2 is allowed Arm 2 Protons: Highest achievable dose between 60-70 Gy (RBE) at 2 Gy (RBE) once daily plus platinum-based doublet chemotherapy Plan must meet dose and volume constraints of all OARs
Stage III Trials Ongoing and planned trials evaluating proton therapy Preoperative therapy Hypofractionated IMPT with simultaneous integrated boost
Conclusions RTOG 0617 set the bar high : 28 month median OS Modern staging (FDG-PET) Sophisticated Treatment Planning Whether altering fractionation, dose , or treatment particle will improve outcomes is unclear Proton therapy has potential to permit less toxic delivery of intensive RT … but limited data Treatment techniques rapidly evolving (IMPT/CBCT) PT may facilitate getting to the the right RT schedule