F The impact on RADIOTHERAPY Giovanna Mantello AOU Osp. Riuniti Ancona gio@mobilia.it
RADIOTHERAPY OF PULMONARY LESIONS INTENSITY MODULATION HIGH GRADIENT DOSE DOSE ESCALATION IPOFRACTIONATION STEREO BODY IMRT IJROBP 2005, 63(1):179 TAKAJAMA K, IJROBP 2005, 61(5):1565 WOLF J, IJROBP 2004, 60(1):186
O R G A N M O T I O N
- QUANTIFY - COMPENSATE - REDUCE PTV IM SM CTV interfraction SET UP ERROR ORGAN MOTION intrafraction ORGAN MOTION OAR
IMAGING inside BUNKER ON BOARD IMAGER Clinac 21 EX RX tube max 150 kv Flat panel asi
kv DRR kv DRR kv 2D/2D MATCH kv -DRR
CBCT 3D/3D MATCH CBCT-CT sim Bone = isocentre surrogate on line adjustement of Set Up
CBCT 3D/3D MATCH CBCT-CT sim on line correction of interfraction OM
CBCT
INTRAFRACTION OM = IT S NOT CORRECTED BY CBCT
SO WHAT CAN WE DO TO STUDY AND TO CORRECT INTRAFRACTION OM
INTRAFRACTION Organ Motion measure reduce A) A) general interventions patient feedback, either auditory or or visual B) B) control the the tumor motion abdominal compression breath holding C) C) allow free free tumor motion but butmaintain a constant target position in in the the beam s eye eyeview when the the beam is ison: respiratory gating beam tracking couch-based motion compensation
MEASURE RX FLUOROSCOPY
MEASURE CT Exhale + CT Inhale EXHALE INHALE ITV EXHALE INHALE
MEASURE CT 4D End-exhale Mid-exhale Mid-inhale End-inhale ITV
End-exhale Mid-exhale Mid-inhale End-inhale >Margin = dose at healthy lung Tumor Dose Lung Dose 5 y local control rates increase 1.3 % for every 1 Gy above 70 Gy ( Kong FM - IJROBP 2005) Constraints to limit the risk of RP (QUANTEC IJROBP 2010)
INTRAFRACTION ORGAN MOTION : WHICH MARGIN? free breathing INSP EXP ADAPTED MARGIN free breathing ABDOMEN CONSTRICTION Breath hold Free breathing GATING Free breathing TRACKING
MARGIN REDUCTION by ABDOMEN CONSTRICTION
MARGIN REDUCTION by BREATH HOLD exp Active Passive ACTIVE BREATHING CONTROL DIBH insp BEAM ON FREE BREATH HOLD WITHOUT MONITORING
MARGIN REDUCTION by TUMOR TRACKING TECHNIQUES
MARGIN REDUCTION by RESPIRATORY GATING INSP BEAM ON EXP INSP BEAM OFF
RESPIRATORY GATING = RADIOTHERAPY SYNCRONIZED WITH RESPIRATORY CYCLE Marker box Shift = respiratory motion surrogate INSIDE BUNKER On console
RESPIRATORY GATING PATIENT SELECTION SIMULATION Work flow PLANNING SET UP AND DELIVERY
RESPIRATORY GATING REPRODUCIBILITY PATIENT SET UP : correspondence of isocentre/bone + TUMOR SET UP : reproducibility of home position overlapping track: sim = treatment Tumor in BEV (gated fluoroscopy + gated kv)
Diagnostic fluoroscopy EVALUATION OF LESION MOTION PA OBL LAT
SIMULATION INSIDE BUNKER COACHING AUDIO VIDEO FEED BACK TRACK ACQUISITION FLUOROSCOPY ACQUISITION
FLUOROSCOPY and TRACK analysis FLUOROSCOPY FIELD: GANTRY 20 OBL ANT SX
TUMOR MOTION vs EXTERNAL MARKER MOTION ATTILO ALDINA SCOPIA OBL A SX 12 10 8 Spostamento (mm) 6 4 SURROGATO LL TARGET (+y=mediale) CC TARGET (+y=caudale) OBL A SX 2 0 14 24 34 44-2 Tempo (s)
GATING TYPOLOGY ampiezza fase - Phase / amplitude INSP/ ESP TECHNIQUES -Gating window - Respiratory device audio - video How to choose the gating window? (beam on) best compromise between residual motion (min) and duty cycle (max) to warranty the right time to deliver the right dose.
GATING TYPOLOGY PHASE vs AMPLITUDE ampiezza fase fase fase fase
TRACK ( PATIENT ADAPTED DATA) DATI TRACCIATO RESPIRATORIO: Tempo di inspirazione= 2.8 s Tempo di espirazione= 4.9 s Periodo respiratorio= 7.7 s DATI FINESTRA DI GATING: Finestra scelta: 90%-10% Duty Cycle= 21% Increase Treatment Time= X 4.8 Gated Motion= 3.9 mm IMPOSTAZIONI AUDIO SIMULAZIONE: Automatico Inhale increment = 0.5s Exhale increment = 0.5s TIPOLOGIA GATING = FASE - INSPIRAZIONE
INSPIRATORY PROSPECTIVE CT insp eu
Residual motion measurement: MARGIN CTV - ITV ATTILO ALDINA SCOPIA OBL A SX Spostamento (mm) 12 11 10 9 8 7 6 5 4 3 2 1 0 14-1 24 34 44 Tempo (s) SURROGATO OBL 20 TARGET (+y=mediale) CC TARGET (+y=caudale) GATE Treatment plan
SET UP inside BUNKER : CBCT patient position verify SET UP ERROR CORRECTION
SET UP inside BUNKER tumor home position verify COACHING TO HAVE pre treatment TRACK = simulation TRACK +/- Simulation track
SET UP inside BUNKER: TUMOR home position verify gated kv gated fluoroscopy BEAM ON BEAM OFF TO VERIFY TUMOR POSITION INSIDE SELECTED GATING WINDOW
Gated PVI during RT to confirm tumor home position TO VERIFY TUMOR POSITION INSIDE SELECTED GATING WINDOW
PVI cine to confirm home position TO CONFIRM CORRECTNESS OF PRE- TREATMENT RESIDUAL MOTION EVALUATION
TREATED PATIENTS DEPT RADIOTHERAPY OF ANCONA 35 patients treated for pulmonary nodule by IGRT (LINAC 21ex) 15/35 evaluated for respiratory GATING - target motion > 5 mm - peripheral primary lesions in non-operable patients - single metastatic lesion - close connection with OAR (heart) to keep off the lesion to heart - target = left breast 10/35 really treated by GATING
CASE CASE AA Single metastasis in pneumectomy patient
CASE CASE BB Lung tumor in heart patient
CASE CASE CC Retrocardiac mass Insp GATING BEAM ON BEAM ON GATED PVI
CASE CASE DD LEFT BREAST RT VOLUME POLMONARE TOTALE EUPNOICO 2404 cm 3 INSPIRATORIO 4893 cm 3 POLMONE SN EUPNOICO 1095 cm 3 INSPIRATORIO 2222 cm 3 DENSITA POLMONARE EUPNEA 0,374 g/cm 3 INSPIRAZIONE 0,162 g/cm 3 gated fluoroscopy gated PVI Beam On
Take home RESPIRATORY GATING : 1. Lesion shift > 5 mm at least in a spatial coordinate 2. Optimal visualization of target (directly or by implanted markers) during simulation and treatment 3. Clinical advantage Patient selection 4. Good patient compliance
Take home RESPIRATORY GATING : advantage Reduce ITV / Reduce pulmonary density/ Reduce dose at healty lung To keep off target to OAR disadvantage Increase of time for planning and delivery (physisist and physician ) > time inside bunker for the patient > linac occupacy > quality assurance of device > dose for imaging
The importance of reproducibility Take home of home position
Take home The importance of reproducibility of home position +/- - camera position - Bunker light coaching marker box Position and Angle
Take home The importance of reproducibility of home position CT Acquisition
WARNING!! The MOTION OF EXTERNAL SKIN MARKER IS ONLY A SURROGATE OF RESPIRATORY CYCLE ATTILO ALDINA SCOPIA OBL A SX 12 evaluate correlation between marker motion and tumor Spostamento (mm) 10 8 6 4 2 SURROGATO LL TARGET (+y=mediale) CC TARGET (+y=caudale) 0 14 24 34 44-2 Tempo (s)
Conclusions?
Conclusions measure reduce A) A) general interventions patient feedback, either auditory or or visual B) B) control the the tumor motion abdominal compression breath holding C) C) allow free free tumor motion but butmaintain a constant target position in in the the beam s eye eyeview when the the beam is ison: respiratory gating beam tracking couch-based motion compensation
Conclusions INTRAFRACTION ORGAN MOTION free breathing INSP EXP ADAPTED MARGIN free breathing ABDOMEN CONSTRICTION Breath hold Free breathing GATING Free breathing TRACKING