Ex-situ lung BNCT at RA-3 Reactor: computational dosimetry and boron biodistribution study Ex-situ lung BNCT at RA-3 Reactor: computational dosimetry and boron biodistribution study * Farias R.O. a,b, * Garabalino M.A. a, Trivillin V.A. a,b, Ferraris S. c,Santa María J. c,Lange F. c,,Monti Hughes A. a,Pozzi E.C.C. a,Thorp S. a, Curotto P. a,Miller M. a,Santa Cruz G.A. a,Bortolussi S. d,Altieri S. d,Portu A. a,b, Saint Martin G. a,Schwint AE a,b y González S.J. a,b a Comisión Nacional de Energía Atómica (CNEA), Argentina. b Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina. C CIDME, Universidad Maimónides, Argentina. d Dipto. di Fisica Nucleare e Teorica (U.Pavia) e Instituto Nazionale di Fisica Nucleare,Italia. * These authors contributed equally 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

Multi-institutional Project CNEA Maimónides University Roffo Oncologic Institute Favaloro Foundation Objetive: Feasibility of ex-situ BNCT for metastatic diffuse lung cancer Lung is the most frequent metastatic location for many tumours Metastatic Ewing Sarcoma Metastatic Wilms Sarcoma Lung metastases from colon carcinoma NSCLC Oligometastases Metastatic Ewing Sarcoma Metastatic Wilms Sarcoma Lung metastases from colon carcinoma NSCLC Oligometastases 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

Ex-situ BNCT in lung - Workflow Administración del compuesto Borado Técnica Quirúrgica de Ablación del órgano Irradiación extracorpórea del órgano con neutrones Re-implantación del órgano o Autotransplante Boronated compound (BPA) infusion RA – 3 Reactor Lung irradiation Thermal Neutrons RA – 3 Reactor Lung irradiation Thermal Neutrons Surgery Lung Ablation Surgery Lung Ablation Surgery Lung re-implantation (Autotransplant) Surgery Lung re-implantation (Autotransplant) Transport Medical CenterAtomic Center ¿Why do this…? “Biological Targeting” non conformational, Allow treatment to infiltrating cells, non visible by imaging techniques and/ or plausible of geometrical delimitation BNCT Avoid healthy tissues (heart, spinal cord, lymphatic nodules, etc.) surrounding the lung Maximize the dose to the tumoral volume Isolated lung irradiation Avoid compatibility issues associated to regular transplant between donor and recipient Autotransplant 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

CNEA Maimónides University Phase I: Pre-clinical studies Ovine Model (Big Animal Model) Boron biodistribution Surgical technique optimization Healthy lung radiotolerance Dosimetry & Treatment Planning Treatment planning for human lung irradiation 3D dosimetry in the RA-3 reactor Small Animal Model In-situ BNCT therapeutic potential Presented in Plenary Biology 1 (June 16th) 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

Surgery “tuning” lung ablation and re-implantation Boron kinetics and biodistribution studies Boron concentration in lung during the explanted period To human Patient Dose prescription and Treatment planning Computational Dosimetry Treatment dosimetric assessement Healthy Lung Irradiation and radiotolerance study Stage I/II Clinical Treatment in patients 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

Average ablation surgery duration 80 minutes (from end of infusion) Surgery “Tuning” BPA Biodistribution Dose Prescription Treatment planning Treatment evaluation Adequate lung ablation for reimplantation Dedicated extensions to maximize lung re-implant efficiency Post-surgery critical cares required 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

Workflow Sampling over explanted lung entire volume Lung perfusion for preservation during explanted period Right lung ablation Explanted organ boron distribution study begins End of boron kinetic study Sampling of several tissues over 5 hours (Blood, Lung, Skin, Urine) End of I.V. infusion Blood sampling during BPA infusion Begins I.V. Infusion BPA 0,14 M duration 45 min Final dose: 350 mg BPA/Kg Sampling Pre-infusion (Skin, blood, Urine) Biodistribution protocol begins (Boron Kinetics study) Surgery “Tuning” BPA Biodistribution Dose Prescription Treatment planning Treatment evaluation BPA Absolute [ 10 B] [Lung/Blood] [ 10 B] ICP-OES or ICP-MS Sonication 90 min. Digestion H2SO4/HNO 3 1:1 1 h 100ºC [B] measured by ICP-OES/ICP-MS [B] microdistribution by Autoradiography Boron Kinetics study in healthy adult sheep Boron concentration in the sheep explanted lung 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

1.Big animal model validated as pre-clinical model in terms of biodistribution. 2.Boron distribution homogeneous in both lung volumes. 3.Lung to Blood ratio remain constant at 1.2±0.7 from t=120 min Surgery “Tuning” BPA Biodistribution Boron kinetics in healthy adult sheep [B] measured data fitted by a two- compartment model (WS Kiger III et al, 2001) 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

[ 10 B] Lung [ 10 B] Lung post-perfusion 23.4±0.6 ppm10.9±0.8 ppm Mean retention factor 0.46± 0.03 Surgery “Tuning” BPA Biodistribution Boron Concentration in Explanted lung after perfusion Partial Boron washout is expected due to lung perfusion 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

10 B tumour to normal tissue ratio (T/N ratio) ReferenceT/N ratio Trivillin et al (2013)1.9Colon ca. Mets in rat Bortolussi et al (2011)>3Colon ca. Mets in rat Suzuki et al (2008/2012) Mesotelioma patient Suzuki et al (2007)1.6Mesotelioma in rats Suzuki et al (2008)3Lung mets in patient Surgery “Tuning” BPA Biodistribution Dose prescription Treatment Planning Treatment evaluation CBE/RBELungTumour 10 B(n,α) 7 Li1.4 (*) N(n,p) 14 C3.2 Fast neutrons3.2 γ-rays11 Mean Lung dose <7.5 Gy (derived from Van Dyk et al. 1981) Healthy lung dose constraint Photon weighted dose Inclusion criteria T/N ratio ≥ 2 *Early breathing rate end point JL Kiger et al, th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

Surgery “Tuning” BPA Biodistribution Dose Prescription Treatment Planning Treatment Evaluation Ezeiza Atomic Centre Internal air cavity surrounded by graphite Quasi –homogeneous flux (10 10 n cm -2 s -1 ) from all directions Ezeiza Atomic Centre Internal air cavity surrounded by graphite Quasi –homogeneous flux (10 10 n cm -2 s -1 ) from all directions Thermal Column - RA-3 Reactor MC reconstruction using MultiCell algorithm Treatment planning in MCNP6 Human collapsed lung CT scan as will be treated LungLung 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

Surgery “Tuning” BPA Biodistribution Dose Prescription Treatment Planning Treatment Evaluation Dose distribution in human lung volume 397 sec (~6.5 min) Clinical scenario Entire volume cannot be tumour Limited number of nodules spread in the healthy lung volume Clinical scenario Entire volume cannot be tumour Limited number of nodules spread in the healthy lung volume Mean dose = 7.5 Gy W T/N ratio = 3 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

Tumour control probability (TCP) model Surgery “Tuning” BPA Biodistribution Dose Prescription Treatment Planning Treatment Evaluation We chose a TCP model used in photon fractionated RT (Martel et al 1999) Find RT equivalent doses in a hypo-fractionated scheme (BNCT, SBRT) using a survival model Adjust the survival model (modified Hugh- Kellerer) from experimental data in cells (H460 – NSCLC) Apply the adjusted survival model to the TCP model Verify the results! (compare TCPs obtained with the model versus the reported in SBRT) Generate 10 tumoral nodules randomly distributed in the lung Repeat the N times Derive TCP in each case. Generate 10 tumoral nodules randomly distributed in the lung Repeat the N times Derive TCP in each case. 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

Big animal model validated as pre-clinical model in terms of biodistribution. Blood, Lung and Skin boron concentration are qualitatively and quantitatively equivalent to human. Boron distribution is homogeneous in the lung volume. Valid for both lungs. After perfusion, explanted lung boron concentration was determined and average retention factor calculated. Conclusions: 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

Treatment planning was simulated for human lung in the RA-3 reactor considering published lung dose prescription and T/N ratios, Irradiation duration is lower than 10 minutes. Promising doses are achievable for T/N ratios higher than 2. An average number of controlled nodules higher than 0.8 is expected when a dedicated TCP model is applied. A feasible and promising treatment technique is being developed for lung metastatic nodular tumours. Eleven experiences were performed in the last 2 years. 7 Autotransplant surgery “tuning”, 3 biodistribution studies, 1 Autotransplant surgery with Irradiation Conclusions (cont.): 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland

Thank you very much for your time 16 th International Congress on Neutron Capture Therapy June 14-19, 2014 Helsinki, Finland