Stereotactic Cyberknife based radiotherapy in Liege introduction possible dosimetric comparisons ?

Nicolas Jansen April 2011

The pendulum swings …

The pendulum swings …

• From simple to complex • From medium dose to ultra high dose • From large volumes to small volumes • From unefficient to very efficient ?

• From surgery to radiotherapy ??

• From cheap to expensive ??? (or …)

Example for lung SRS …

Rapid introduction in clinical practice

Acta Oncol. 1995;34(6):861-70. Stereotactic high dose fraction radiation therapy

of extracranial tumors using an accelerator. Clinical experience of the first thirty one patients.

Blomgren H

et al. Karolinska Hospital, Stockholm, Sweden Int J Radiat Oncol Biol Phys. 2000 Sep 1;48(2):449-57. Megavoltage CT-assisted stereotactic radiosurgery for thoracic tumors: original research in the treatment of thoracic neoplasms.

Nakagawa K et al

. University of Tokyo, Tokyo, Japan

200 160 120 80 40 0 1990-1995 1996-2000 2001-2005 2006-2010 Publications on stereotactic lung radiotherapy

Example for lung SRS …

In Belgium ?

Curr Probl Cancer. IMRT.

2003 Van Houtte P

Jan-Feb;27(1):60-3.

New potentials of radiotherapy in non-small cell lung cancer: stereotactic therapy and . Radiation Department, Institute Jules Bordet, Brussel J Vasc Interv Radiol.

2005

Jan;16(1):51-6. Percutaneous placement of marking coils before stereotactic radiation therapy of malignant lung lesions.

de Mey J et al.

Department of Radiology, UZ Brussel Cancer Radiother.

2010

Oct;14(6-7):446-54 Gating and tracking, 4D in thoracic tumours.

Verellen D et al

. Department of Radiotherapy, UZ Brussel Int J Radiat Oncol Biol Phys. Phase II Trial.

Bral S, et al 2010

Aug 12. Prospective, Risk-Adapted Strategy of Stereotactic Body Radiotherapy for Early-Stage Non-Small-Cell Lung Cancer: Results of a . Department of Radiotherapy, UZ Brussel

VUB Belgian RT centers or sattelites Centers doing stereotactic lung radiotherapy Centers doing full tracking based and 4D adapted stereotactic lung radiotherapy 1990-1995 1996-2000 2001-2005 2006-2010 2011-2015

• Assessment of the uncertainties in dose delivery of a commercial system for linac based stereotactic radiosurgery Verellen D, et al. - Int J Radiat Oncol Biol Phys. 1999-5 1;44(2):421-33

Are there any quality differences in stereotactic radiotherapy approaches ?

• Differences based on …

– Experience – Internal workflow and quality control – Technical differences in treatment delivery system • Beam characteristics • Tracking capabilities • …

What are the different systems for stereotactic radiotherapy delivery ?

• Stereotactic placement of sources for prostate brachytherapy • (Very conformal treatments) • Classical linac based (Novalis) • Tomotherapy based systems • Purpose build stereotactic devices with inherent 4D capabilities – Vero – Cyberknife

•

Comparison of stereotactic approaches

– Ideally : clinical outcome based (long time effort) • Narrow comparison : between stereotactic systems • Wider comparison : Stereotactic radiotherapy versus … protontherapy, surgery , targeted systemic therapies, … – Dosimetric comparison • Narrow comparison : between stereotactic devices • Wider comparison : stereotactic systems relative to a more ‘classical approach’ to be able to justify the stereotactic approach

Comparing radiotherapy approaches

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• •

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Clinical outcome Dosimetric Time Cost Availability Acceptability

Comparing radiotherapy approaches

• • •

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Clinical outcome Dosimetric Time Cost Availability Acceptability

Dosimetric comparison

• How to compare ?

– For each OAR : different DVH parameters – For the PTV : the coverage, … (indices) • But cheating is possible – (Forgetting) margin management – Look only at high dose regions – Non standardised planning goals and efforts

Dosimetric comparison

• How to compare plan results ?

– DVH comparison • Curve form • Key DVH parameters – DVH indices – Dose distribution itself • (not to loose geographical information)

Dosimetric comparison

• How to compare plan results ?

– DVH comparison • Curve form • Key DVH parameters – DVH indices – Dose distribution itself • (not to loose geographical information)

100 90 80 70 60 50 40 30 20 10 0 2 6 10 14 18 22 26 30 34 38 42 46 52 56 60 Structure 1, plan 1 Structure 1, plan 2

Dosimetric comparison

• How to compare plan results ?

– DVH comparison • Curve form • Key DVH parameters – DVH indices – Dose distribution itself • (not to loose geographical information)

100 90 80 70 60 50 40 30 20 10 0 2 6 10 14 18 22 26 30 34 38 42 46 52 56 60 Structure 1, plan 1 Structure 1, plan 2

Dosimetric comparison

• DVH derived parameters – Validated for stereotatic treatments ?

– Are they clinically relevant ?

• Which ones do we want to analyse ?

– Single point constraints/limits • Vx • Dx – Mathematically derived parameters • CI, DHI, – Tumor response models • Lyman NTCP model • Local Radiation Response - Organ Functional Reserve Models

Dosimetric comparison

• DVH derived parameters – Validated for stereotatic treatments ?

– Are they clinically relevant ?

• Which ones do we want to analyse ?

– Single point constraints/limits • Vx • Dx – Mathematically derived parameters • CI, DHI, – Tumor response models • Lyman NTCP model • Local Radiation Response - Organ Functional Reserve Models

DVH parameters

• CI :

– V ref isodose / V target volume – Conformity index – A ratio of VOLUMES – Ideally CI = 1 – RTOG radiosurgery quality guidelines : • CI = 1.0 to 2.0

• CI = 0.9 to 1.0 or 2.0 to 2.5 : minor deviation • CI < 0.9 or CI > 2.5 : major deviation

DVH parameters

• CI :

– Min isodose surrounding the target / Reference isodose – Coverage index – A ratio of DOSES – Ideally 100% – RTOG radiosurgery quality guidelines : • CI > 90% : adequate • CI 80% to 90% : minor deviation • CI < 80% : major deviation

DVH parameters

• HI :

– Max isodose in the target / Reference isodose – Homogeneity Index – A ratio of DOSES – Ideally HI = 1 ? NO, if hot spots are inside the GTV – RTOG radiosurgery quality guidelines : • HI 1.0 to 2.0 : adequate • HI 2.0 to 2.5 : minor deviation • HI > 2.5 : major deviation

Dosimetric comparison

• Pre-analysis standardisation – Equal image set used – Identical GTV-CTV – Identical dose and fractionation • But … – Not all systems require the same immobilisation – Different treatment execution errors and different tracking parameters can induce different … margins

Margins …

• Reflect the imprecisions and errors of the whole treatment preparation and delivery chain • GTV to CTV : should be identical • CTV to PTV : to be re analysed for each technique • Are a source of … errors – Unrealistic margins – Should be adapted to … new imprecisions • Marker tracking • …

Ablative dose, no ablative results

• If the dose is ablativen why is the LC after the treatment not 100% – The staging was incomplete or inaccurate – The dose is not ablative because of radioresistance – Geographical miss

What do we know about comparisons in stereotactic radiotherapy ?

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First data

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Dosimetric comparison of stereotactic radiosurgery to intensity modulated radiotherapy

- Kramer BA, Wazer DE, Engler MJ, Tsai JS, Ling MN - Radiat Oncol Investig. 1998 ;6(1):18-25.

–

Dosimetric comparison of stereotactic body radiotherapy in different respiration conditions: a modeling study

Kontrisova K, Stock M, Dieckmann K, Bogner J, Pötter R, Georg D - Radiother Oncol. 2006 Oct;81(1):97-104 –

Dosimetric comparison of linear accelerator-based stereotactic radiosurgery systems

- Sharma SD, Kumar S, Dagaonkar SS, Bisht G, Dayanand S, Devi R, Deshpande SS, Chaudhary S, Bhatt BC, Kannan S - J Med Phys. 2007 Jan;32(1):18-23.

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What do we know about comparisons ?

Not cyberknife related : hot topic last 6 months!

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Cost-Effectiveness Analysis of Stereotactic Body Radiotherapy and Radiofrequency Ablation for Medically Inoperable, Early-Stage Non-Small Cell Lung Cancer

- Sher DJ, Wee JO, Punglia RS - Int J Radiat Oncol Biol Phys. 2011 Feb 10 –

Comparison of stereotactic brachytherapy (125 iodine seeds) with stereotactic radiosurgery (LINAC) for the treatment of singular cerebral metastases

- Ruge MI, Kocher M, Maarouf M, Hamisch C, Treuer H, Voges J, Sturm V - Strahlenther Onkol. 2011 Jan;187(1):7-14 –

Stereotactic radiotherapy for peripheral lung tumors: a comparison of volumetric modulated arc therapy with 3 other delivery techniques

- Ong CL, Verbakel WF, Cuijpers JP, Slotman BJ, Lagerwaard FJ, Senan S - Radiother Oncol. 2010 Dec;97(3):437 42 –

Randomised phase I/II study to evaluate carbon ion radiotherapy versus fractionated stereotactic radiotherapy in patients with recurrent or progressive gliomas: the CINDERELLA trial

Combs SE, Burkholder I, Edler L, Rieken S, Habermehl D, Jäkel O, Haberer T, Haselmann R, Unterberg A, Wick W, Debus J - BMC Cancer. 2010 Oct 6;10:533 –

Dose-volume comparison of proton radiotherapy and stereotactic body radiotherapy for non-small-cell lung cancer

- Kadoya N, Obata Y, Kato T, Kagiya M, Nakamura T, Tomoda T, Takada A, Takayama K, Fuwa N - Int J Radiat Oncol Biol Phys.

2011 Mar 15;79(4):1225-31 –

Dosimetric comparison of intensity-modulated stereotactic radiotherapy with other stereotactic techniques for locally recurrent nasopharyngeal carcinoma

Biol Phys.

2011 Jan 1;79(1):71-9.

- Kung SW, Wu VW, Kam MK, Leung SF, Yu BK, Ngai DY, Wong SC, Chan AT - Int J Radiat Oncol

•

What do we know about comparisons ?

Cyberknife related

–

A dosimetric comparison between Gamma Knife and CyberKnife treatment plans for trigeminal neuralgia

- Descovich M, Sneed PK, Barbaro NM, McDermott MW, Chuang CF, Barani IJ, Nakamura JL, Lijun M - J Neurosurg. 2010 Dec;113 Suppl:199-206 (University of California, San Francisco) –

A dosimetric comparison of stereotactic body radiation therapy techniques for lung cancer: robotic versus conventional linac-based systems

Texas Southwestern Medical Center, Dallas) - Ding C, Chang CH, Haslam J, Timmerman R, Solberg T - J Appl Clin Med Phys. 2010 Jun 29;11(3):3223 (University of –

Intracranial radiosurgery in the Netherlands. A planning comparison of available systems with regard to physical aspects and workload

- Schoonbeek A, Monshouwer R, Hanssens P, Raaijmakers E, Nowak P, Marijnissen JP, Lagerwaard FJ, Cuijpers JP, Vonk EJ, van der Maazen RW - Technol Cancer Res Treat. 2010 Jun;9(3):279-90 (Radboud University Nijmegen Medical Centre, Nijmegen) –

Quality of radiosurgery for single brain metastases with respect to treatment technology: a matched-pair analysis

- Wowra B, Muacevic A, Tonn JC. - J Neurooncol. 2009 Aug;94(1):69-77 –(European CyberKnife Center Munich) –

Comparison of advanced irradiation techniques with photons for benign intracranial tumours

- Cozzi L, Clivio A, Bauman G, Cora S, Nicolini G, Pellegrini R, Vanetti E, Yartsev S, Fogliata A - Radiother Oncol. 2006 Aug;80(2):268-73 (Oncology Institute of Southern Switzerland, Medical Physics, Bellinzona, Switzerland ) –

Dosimetric comparison of CyberKnife with other radiosurgical modalities for an ellipsoidal target

- Yu C, Jozsef G, Apuzzo ML, Petrovich Z - Neurosurgery. 2003 Nov;53(5):1155-62 (University of Southern California, Los Angeles)

A dosimetric comparison between Gamma Knife and CyberKnife treatment plans for trigeminal neuralgia

- Descovich M, Sneed PK, Barbaro NM, McDermott MW, Chuang CF, Barani IJ, Nakamura JL, Lijun M - J Neurosurg. 2010 Dec;113 Suppl:199-206 (University of California, San Francisco)

Discussion : what treatment planning efforts have been done ?

Less beams in CK !

A dosimetric comparison of stereotactic body radiation therapy techniques for lung cancer: robotic versus conventional linac-based systems

- Ding C, Chang CH, Haslam J, Timmerman R, Solberg T - J Appl Clin Med Phys. 2010 Jun 29;11(3):3223 (University of Texas Southwestern Medical Center, Dallas)

• n=8 / common contours / 3x20 Gy • 4D CT scan

→

MIP creation • PTV 3D created, also PTV 4D

A 4D CT scanning is performed.

A 3D conformal linac- SBRT plan is designed on ITV and corresponding PTV 3D.

A deformable registration method is then applied to obtain the 4D cumulative dose distribution.

GTV and PTV 4D are contoured on the 50% phase of 4D CT images, which corresponds to the maximum exhalation.

The 50% phase of 4D CT images and contour sets of GTV and PTV 4D are sent to CyberKnife system for Synchrony planning.

CI =

conformity index

= the ratio of the tissue volume receiving the prescription isodose or more to the tumor volume

Intracranial radiosurgery in the Netherlands. A planning comparison of available systems with regard to physical aspects and workload

- Schoonbeek A, Monshouwer R, Hanssens P, Raaijmakers E, Nowak P, Marijnissen JP, Lagerwaard FJ, Cuijpers JP, Vonk EJ, van der Maazen RW - Technol Cancer Res Treat. 2010 Jun;9(3):279-90 (Radboud University Nijmegen Medical Centre, Nijmegen) • 5 systems – CK – Gammaknife – Novalis 3 mm leafs – Tomotherapy – Linac 10 mm leafs • GTV + 2 mm = PTV (fixed for all systems) • N = 5 patients (skull base tumors) – 3 size levels • Dose prescribed : 80% isodose surrounding the PTV

• 3 target volumes

– 0.1 ml : no system can respect the conformality index (all >3.0) – 0.5 ml : better for CK, GK – 1.0 ml : all systems respect RTOG

Quality of radiosurgery for single brain metastases with respect to treatment technology: a matched-pair analysis

- Wowra B, Muacevic A, Tonn JC. - J Neurooncol. 2009 Aug;94(1):69-77 –(European CyberKnife Center Munich) • With a matched-pair analysis we were able to prove that identical quality of clinical results in single brain metastases can be achieved with the GK and the CK.

• Furthermore we could show that the radiosurgical dose can be better tailored to the target with the CK than with the GK.

• This result, a more homogeneous dose distribution, and a lower peripheral dose represent an advantage of the CK in regard of the radiation protection

Comparison of advanced irradiation techniques with photons for benign intracranial tumours

- Cozzi L, Clivio A, Bauman G, Cora S, Nicolini G, Pellegrini R, Vanetti E, Yartsev S, Fogliata A - Radiother Oncol. 2006 Aug;80(2):268-73 (Oncology Institute of Southern Switzerland, Medical Physics, Bellinzona, Switzerland )

AMOA = intensity modulated arc therapy HT = helical thomotherapy

Dosimetric comparison of CyberKnife with other radiosurgical modalities for an ellipsoidal target

- Yu C, Jozsef G, Apuzzo ML, Petrovich Z - Neurosurgery. 2003 Nov;53(5):1155-62 (University of Southern California, Los Angeles)