Functional image-based adaptive IMRT: dream or reality? Vincent - PowerPoint PPT Presentation

Functional image-based adaptive IMRT: dream or reality? Vincent GREGOIRE, MD, PhD, Hon. FRCR Radiation Oncology Dept. Head and Neck Oncology Program & Center for Molecular Imaging and Experimental Radiotherapy, Université Catholique de Louvain, St-Luc University Hospital, Brussels, Belgium IAEA April 2009

IMRT for Head and Neck Tumors IMRT for Head and Neck Tumors PTV 69 Gy Oropharyngeal SCC Larynx T2-N0-M0 PTV 55.5 Gy PRV Spinal cord SIB-IMRT: 30x2.3 Gy Left parotid Right parotid 30x1.85 Gy IAEA April 2009

Challenges in Head & Neck loco-regional treatment • Target selection and delineation • Adaptive IMRT: geometrical, biological & dosimetrical •which imaging modalities? •which biological pathways? •which volume/dose registration algorithms? •how frequently? • Concomitant association with drugs and/or “small molecules” IAEA April 2009

NMR (T1) CAT Scan 18 F-FDG PET April 2009 IAEA

5 cm Macroscopy 5 cm CAT Scan 5 cm 18 F-FDG PET IAEA Daisne et al , 2004 April 2009

How far are we from the truth ? IAEA Daisne et al , 2004 April 2009

The “ground truth” GTV Vol (ml) Mismach x/CT Mismach x/MR Mismach x/PET Mismach x/macro CT 20.8- 26% 48% 81% ? MR 23.8 45% - 67% 107% FDG-PET 16.3* 17% 15% - 47% Macro 12.6* 10% 9% 13% - *p<0.05 (Wilcoxon rank test) IAEA Daisne et al , 2004 April 2009

Image-Guided Radiation Therapy in HNSCC Impact of imaging modality on dose distribution CT-based target volume FDG PET-based target volume IAEA Geets et al , 2006 April 2009

Validation protocol in locally advanced HNSCC Apport de l'imagerie fonctionnelle par Tomographie par Emission de Positrons (TEP) dans le ciblage biologique par radiothérapie de conformation (3D-CRT) et par modulation d'intensité (IMRT) de tumeurs ORL Use of functional imaging with PET for target volume delineation in 3D-CRT/IMRT for head and neck tumors Prof. V. Grégoire, UCL St-Luc, Brussels, Belgium Prof. E. Lartigau, COL, Lille, France Dr. JF Daisnes, Cliniques St-Elisabeth, Namur, Belgium IAEA April 2009

4D-IMRT The Cathedral of Rouen IAEA C. Monet, 1894 April 2009

CT MRI (T2) FDG-PET PRE-R/ (Week 2) WEEK 3 (Week 4) WEEK 5 IAEA April 2009

Biological adaptive IMRT Before R/ Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 R/ start Images acquisitions CT MR T2 FS MR T2 FDG-PET Anatomic imaging Dynamic FDG-PET • 10 patients with stage III-IV pharyngo-laryngeal SCC treated by CT- RT • Images acquired before R/ and during RT after means doses of 14, 25, 35 and 45 Gy. IAEA Geets, 2006 April 2009

Image-Guided Radiation Therapy in HNSCC The 4th dimension … FDG-PET 0 Gy 50 Gy IAEA Geets et al , 2003 April 2009

PET image segmentation during RxTh UG 4mm SBR Raw image Image processing Image segmentation BG 6mm + deconvolution W&C IAEA J. Lee & X. Geets, 2005 April 2009

Impact on dose distribution P<0.001 IAEA Geets, 2007 April 2009

Impact on dose distribution Classic CT-based planning Adaptive PET-based planning SIB-IMRT 30x2.3 Gy 30x1.85 Gy P<0.001 Planning V 10 V 50 V 80 V 90 V 95 V 100 Classic CT-based 100% 100% 100% 100% 100% 100% Adaptive CT-based 99% 100% 100% 85% 80% 66% Classic PET-based 99% 99% 98% 83% 82% 81% Adaptive PET-based 99% 100% 98% 73% 67% 58% IAEA Geets, 2007 April 2009

Variation in therapeutic CTVs during RT-CH… Mean slope: -1.46% / treat day (p<0.05) Mean slope: -2.55% / treat day (p<0.05) Medial shift: 0.91mm after 25# (p<0.05) Lateral shift: 1.52mm after 25# (p<0.05) IAEA Castadot & Lee, 2008 April 2009

Variation in prophylactic CTVs during RT-CH… Mean slope: -0.47% / treat day (p<0.05) Mean slope: -0.41% / treat day (p<0.05) No shift Medial shift: 1.76mm after 25# (p<0.05) IAEA Castadot & Lee, 2008 April 2009

Variation in parotid volumes during RT-CH… Mean slope: -1.03% / treat day (p<0.05) Mean slope: -0.93% / treat day (p<0.05) No shift Medial shift: 3.21mm after 25# (p<0.05) IAEA Castadot & Lee, 2008 April 2009

0 → 14Gy 14 → 25Gy 25 → 35Gy 35 → 45Gy 45 → 69Gy + w2 → w0 + w3 → w0 + w4 → w0 + w5 → w0 Total Dose really received by each volume element of the IAEA patient Castadot & Lee, 2008 April 2009

Dose distribution after adaptive RT-CH (n=5) « Classical » « Classical » « Real » « Real » Adaptive Adaptive CT-based PET-based CT-based PET-based CT-based PET-based Homolat Parotid D mean 22.05 21.63 23.80 23.27 22.91 22.09 (Gy) Heterolat Parotid 18.15 20.00 18.52 19.34 18.57 18.40 D mean (Gy) SC 39.49 39.76 41 42.04 37.90 38.26 D 2 (Gy) Larynx 65.63 66.33 65.37 66.35 65.57 65.37 D 5 (Gy) Oral cavity 37.80 35.18 38.79 36.16 36.01 33.35 D mean (Gy) Mandible 60.59 57.51 59.52 56.77 58.30 57.27 D 2 (Gy) Homolat Submax gl 65.04 62.96 65.52 63.59 64.57 63.09 D mean (Gy) Heterolat Submax gl 54.92 53.77 54.97 53.63 55.11 54.58 D mean (Gy) Skin 11.66 8.78 12.08 9.25 10.25 7.24 V 65Gy (cc) 308.89 297.00 400.11 327.56 311.39 254.40 V 95% (cc) IAEA Castadot & Lee, 2008 April 2009

Which biological pathways? … Hypoxia: 18 F-EF3 Metabolism: 18 F-FDG 11 C-Met Proliferation: 76 Br-BFU IAEA April 2009

Grosu, 2007 The dream … April 2009 IAEA

The reality… Image-Guided Radiation Therapy in HNSCC • Adaptive IMRT: geometrical, biological & dosimetrical • which imaging modalities?? • which biological pathways?? • which volume/dose registration algorithms?? • how frequently?? IAEA April 2009

Acknowledgements • Communication and Remote Sensing Lab. Adriana PARRAGA, Eng. Benoit MACQ,Eng., Ph.D. • ENT and Head & Neck surgery Marc HAMOIR, M.D. • Imaging Emmanuel COCHE, M.D. Thierry DUPREZ, M.D. Max LONNEUX, M.D. • Oral & Maxillo-Facial surgery Pierre MAHY, M.D. Hervé REYCHLER, M.D., D.M.D. • Pathology Birgit WEYNAND, M.D. • PET laboratory Anne BOL, Ph.D. Daniel LABARE, Ph.D. • Radiation Oncology Nicholas CHRISTIAN, M.D. Pierre CASTADOT, M.D. Xavier GEETS, M.D., Ph.D. John LEE, eng., Ph.D. Pierre SCALLIET, M.D., Ph.D. IAEA April 2009