Skin Applicators: Radionuclide based (Valencia ......Commissioning Virtual Focus 28 Esteya and A20 2...

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Skin Applicators: Radionuclide based (Valencia) &

electronic (Esteya)

J. Perez-Calatayud, C. Candela, T. García, J. Bautista, V. Carmona, F. Lliso, J. Gimeno, J. Richart, R. Ballester, O. Pons, R. Botella, F. Celada, M. Hernández, A. Ballesta, S. Rodríguez, M. Santos, A. Tormo, F. Ballester

perez_jos@gva.es

Manchester Clinical Workshop, Jan 21-22, 2016

Disclosure

Research support received from:

• Elekta-Nucletron: Valencia Applicators, Freiburg flap, QA tools, MRI dummies, MC sources, electronic BT: ESTEYA

• PTW: Well chamber inserts, QA tools

La Fe Hospital& Valencia University & Benidorm ITIC

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Content

• Background

• Valencia vs Leipzig

• Esteya vs Valencia

• Commissioning

• QA & Periodic test

• Clinical implementation

• Conclusions

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Skin radiotherapy

Small PTV cases: (area < 3 cm) and depth <3-4 mm

Difficulties using electrons (bolus, specific dosimetry)

Difficulties using flaps & moulds

Brachytherapy Skin applicators

Treatment planning & delivery simpler

High protection surrounding tissue

Radionuclide HDR Applicators (Leipzig & Valencia)

Electronic BT Applicators (Xoft & Esteya)

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Leipzig Applicattors

Courtesy: Varian

Court

esy:

Nucle

tron-E

lekta

Cup-shaped of tungstenHorizontal and VerticalDiameters 1 cm, 2 cm, 3 cm

Plastic cap 1 mm, to reduce skin dose due to electrons

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Leipzig vs Valencia (Elekta)

Lateral homogeneity, penumbra, and useful beam are improved

longer treatment time

Granero et al 2008

Valencia App: new design

Extra shield to reduce tip dose

Granero, Perez-Calatayud, Ballester, Ouhib EJMP 2012

lateral nose eye dose

Same absolute dose distribution as in previous models

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Plastic cap: To avoid electron contamination

Valencia Applicators: Cap

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Plastic cap:To avoid electron contamination

Applicators: Clinical implementation

Granero et al (accepted Med Phys)

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In Progress: New Valencia

Esteya (Elekta)

Designed to obtain dose distributionssimilar to Valencia App

X-ray source 69.5 kV

Adjustable arm

10-30 mm App

Console includes: patientadministration, control Unit (timers, interlocks,…) QA and treatment planning

After dose per fraction, depth and applicator size are selected, the system presents automatically thetreatment time ¡

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!

Esteya vs. Valencia PROFILES

12Penumbra: 1.1 mm vs. 1.9 mm

Esteya vs. Valencia PROFILES

Esteya (3 cm colimator)

Valencia applicator (H3)

SSD 6 cm

SSD 1.6 cm

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Esteya vs. Valencia PDD & Output

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Gradient

Valencia

Esteya

7 Gy treatment time Esteya Valencia H3

App 3 cm @ 3 mm 153s 449-898 s

12% / mm

8% / mm

Garcia et al 2014

Esteya Leackage

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Leackage < 2 Gy/s < 0.01% of the delivered dose

Garcia et al 2014

Esteya shielding requirements

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Work in progress

B. Ibañez, J. Bautista, C. Candela, J. Richart, I. Villaescusa, F. Ballester, J. Perez-

Calatayud. AAPM Annual Meeting Anaheim 2015. Med Phys 42(6) 3495

Exp derived scatter and leackage + 5 cm tissue attenuation

Primary

Secondary

0.82 mm Pb

0.34 mm Pb

1.61 mm Pb

0.71 mm Pb

W: 20 fx/day, 7 Gy/fx

d=1.5 m

T=1

U=1

P=0.02 mGy/week

NCRP-145

Commissioning VALENCIA

Data for clinical use

17EXP validated Monte Carlo

PDD & Output

Granero et al 2008

Valencia H3

http://www.uv.es/braphyqsF. Ballester

Commissioning VALENCIASID & Flatness & Symmetry

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FILM

MULTICHAMBER ARRAY

1319 mm

1320 mm

1321 mm

Commissioning VALENCIA

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FILM

MULTICHAMBER ARRAY

1319 mm1321 mm

SID & Flatness & Symmetry

Commissioning VALENCIA

MC Output check

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Small volume chambercalibrated Co-60 (eg PTW

Markus or PTW PinPoint)

CF reference values for HDR 1000Plus (SI) and TM3304 (PTW)

Perez-Calatayud 2006

Granero 2008

Granero 2012

Commissioning VALENCIA

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CF reference values for HDR 1000Plus (SI) and TM3304 (PTW)

Perez-Calatayud 2006

Granero 2008

Granero 2012

Commissioning VALENCIA

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CF reference values for HDR 1000Plus (SI) and TM3304 (PTW)

Perez-Calatayud 2006

Granero 2008

Granero 2012

Revised according to Comments Gotts MP 2012

Reply Med Phys April 2012

Commissioning VALENCIA

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TPS implementation

Not possible on TG-43 based TPSLibrary plan: 1 dwell position +1 dose point in which the dose rate is equal to the output

Commissioning VALENCIA

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TPS implementation

Library plan: 1 dwell position +1 dose point in which the dose rate is equal to the output

F is used for PDD

F=1 when prescription is done at 3 mm

Data for clinical use

25Automatic treatment time calculation

PDD & Output not accesible to user

Esteya

App size + depth + dose

Commissioning ESTEYAFlatness & Symmetry

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FILM

MULTICHAMBER ARRAY

TG profileLR profile

Commissioning ESTEYA

HVL

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Set-up according TG-61 and TRS-398

Aluminium slabs

Barracuda (solid state) and 0.6 cc farmer

1.88 mm Al 2.09 mm Al

Garcia et al 2014 Candela-Juan et al 2015

Esteya

X-ray Tube

Al slabs

Detector

55 cm

50 cm

To quantify the quality for theselection of the correctionfactors.

Goals

Methodology

Commissioning Virtual Focus

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Esteya and A20

2

0

0 0

1 1 1

( )

cd

c d c

SSD dx x d

SSD d d x x SSD d x

Nominal

Measured

To apply the inverse square law from the effective measuring point of the chamber to the surface

60 mm

59.0 ± 0.7 mm

Candela-Juan et al 2015

xd : reading of the chamber when its top surface is placed at

a distance d from the collimator surface.

x0 : reading of the chamber for d = 0.

dc : depth of the effective point of measurement.

SSD : source to applicator surface distance.

considering dc = 1.8 mm

Commissioning

PDD

Soft X-ray paralell-plate chamber. PTW T34013: 0.0053 cc volume, entrance window thickness 0.03 mm, active diameter 1.7 mm

Plastic water Low Range (CIRS), density 1.03 g/cc.

Typical PDD range for all App: 1% (3 mm) 4% (10 mm)

Garc

ia e

t al 2014

Esteya

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Commissioning

Absolute surface dose rate

Method I Measure in solid water with a chamber calibrated in absorbed dose to water

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0.005 cm3 Soft X-ray chamberType 34013

dc=0.25 mm

Commissioning

Absolute surface dose rate

Traceable to PTB (Germany)

0.005 cm3 Soft X-ray chamber, Type 34013

(k=2)

Calibrated with beam size Ø = 3 cm, with SSD = 75 cm.

Commissioning

Absolute surface dose rate

Method I Measure in solid water with a chamber calibrated in absorbed dose to water

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TRS-398

0.25 mm for T34013 (PTW)

6 cm (Esteya) 1.00 for T34013

From calibration certificate

KpT

Kion

Kpol

Kelec

1.000 More direct and robust¡¡

Commissioning

Absolute surface dose rate

Caution: Equivalence plastic water with liquid water

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Hill et

al 2010

Difference (%) in the dose to a small voxel of water located on the surface of

the phantom material relative to the surface dose in a water phantom

CIRS Plastic Water Low Range: 0.2%

Candela-Juan et al 2015b using MC Penelope with Esteya spectrum

Hill et al 2014

Summary suitable/unsuitable

phantoms for kV dosimetry

Commissioning

Absolute surface dose rate

Method II Measure in air with a chamber calibrated in air kerma

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0.074 cm3 Exradin A20

Commissioning

Absolute surface dose rate

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±1% (k = 2)

ADCL Wisconsin USA

No available the calibration in water

Calibrated with beam size 10x10 cm2, with SSD = 100

cm.

Commissioning

Absolute surface dose rate

Method II Measure in air with a chamber calibrated in air kerma

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TG-61

From Table V TG-61

Depends of: SSD, Ø, HVL

KpT

Kion

Kpol

Kelec

1.000

From calibration certificate

1.80 mm for A20 (SI)

6 cm (Esteya) 1.00 for A20

From Table IV TG-61

Depends of HVL

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T34013 chamber in plastic water

T34013 chamber in air

Exradin A20 chamber in air

Med Phys 2015

Relative difference (%) between the surface dose rates measured and

the surface dose rates included in the Esteya console.

(±2.3%) (±2.7%) (±2.5%) (k=1)

Commissioning

Timer

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Tests

Reproducibility

Accuracy

Linearity

Surface dose, D (Gy) Intensity

D > 4 Gy 1.6 mA

2Gy < D ≤ 4 Gy 1.0 mA

D ≤ 2 Gy 0.5 mA

IONIZATION CHAMBER

Material

JCB 2015JCB 2014

Commissioning ESTEYA

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Applicator interlocks

Indicators

Door interlock (if required)

Radiation area monitor (if required)

Emergency buttons

Arm movements

Console calculation

Timer: reproducibility and accuracy

Timer: main power interruption

QA & Periodic test Valencia

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Independent calculation

Each calculated plan

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Weekly Chart QA

QA & Periodic test Valencia

QA & Periodic test Valencia

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Source To Indexer Distance

Flatness & Symmetry & Penumbra

Output

HDR Ir-192 Source ex change (approx 3-4 moths)

QA & Periodic test ESTEYA

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Independent calculation

Each calculated plan

QA & Periodic test ESTEYA

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Weekly Chart QA

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Periodic tests ESTEYA

Esteya

Self-test

Indicators, interlocks and emergency buttons

Visual inspection of applicators

Output, flatness, PDD constancy

Each treatment day

TG-40 AAPM

TG-56 AAPM

TG-158 AAPM

ESTRO Booklet 8

Eaton 2015 (eBT review)

Manufacturer

Diode QA tool

Specific to daily evaluate constancy of output, flatness, symetry and PDD: 26 diodes

Periodic testQA tool

OK:

Surface Dose Rate Change < 2%

PDD 5 mm Change < 2%

All 9 flatness changes < 2%

Measured radiation time is within 1% of the planned radiation time

Esteya

In our center, change in surface dose rate: +0.5% after 1 year

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Periodic tests

Flatness & symmetry for the 30 mm app

Output and PDD (0 and 3 mm depth) for the30 mm app, with ionization chamber

Monthly Quarterly

3%

2%

Semiannual Annual

Flatness, Output and PDD (0 and 3 mm depth) for ALL app.

2%

JCB 2015

TG-253 (AAPM-ESTRO) Surface Brachytherapy

R. Fulkerson, J. Perez-Calatayud, F. Ballester, I. Buzurovic, D. Harrington, Y. Kim, Y. Niatsetski, Z. Ouhib, S. Pai, M. Rivard, Y. Romg, T. Rusch, FA Siebert, B. Thomadsen, F. Weigand

Societal Recommendations

“Aspects of Dosimetry and Clinical Practice of Skin Brachytherapy: The

American Brachytherapy Society Working Group Report”

Z. Ouhib, M. Kasper, J. Perez-Calatayud , S. Rodriguez, A. Bhatnagar, S.

Pai, J. Strasswimmer.

Brachytherapy 2015

Recommendations Commissioning and QM program for surface brachytherapy

Methods, detectors, traceability, periodic test: frequency & tolerance, and QM under the TG-100 (FMEA) perspective

Future TG-253 Recommendations

TG-100 FMEA approach

Future TG-253 Recommendations

Clinical implementation

HFUS

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Depth determination

Superficial Nodular

High resolution B-scan with 18 mHzhand-held transducer (Siemens AcusonS2000). Gel pad 2 cm x 9 cm (Aquaflex)

Clinical implementationUS vs. punch biopsy

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Depth determination

Superficial Nodular

3 mm diameter punch biopsy on thedeepest site estimated clinically. Depthevaluated with Leica DMD108 digitalmicroimaging network

Ballester, JCB in press

prescribe at 3 mm depth when HFUS measurements give values smaller than this umbral one

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US for depth evaluation and follow-up

Longport Episcan 35MHz

Courtesy Dr E. AllenChristie Hospital

?

Project in evaluation La Fe: US vs OCT vs MRI vs Biopsy

Clinical implementation

Templates: useful beam and outer app contour 54

Patient marking

Clinical implementation

Templates LA FE: useful beam and outer app contour

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Patient marking

Available FREE under request to perez_jos@gva.esthanks to the funding of Elekta (from April 2016)

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Set-up

Applicators: Clinical implementation

10%/mm

Good contact without gaps

Clinical implementation

Valencia

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Patient Set-up

Protective condom

Clinical implementation

Esteya

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Patient Set-up

Plastic wrap

Esteya arm with freedomdegrees and approach tool

Clinical implementation

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Patient Set-up

Approach tool to get full contact

BT skin Apps are very efficient with respect to treatment planning and delivery. Applicator shielding results in high protection of surrounding tissue.

Commissioning and QA procedure is well established.

Esteya is a new electronic brachytherapy system. Compared with the Valencia App there are improvements of penumbra, treatment time, gradient on PTV, leakage.

The low energy and tungsten shielding allows treatment in a minimally shielded environment.

Clinical implementation of both Valencia & Esteya are well established and allow to use a hypofractionated protocol

Conclusions

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References Valencia Group I

perez_jos@gva.es

“Design and evaluation of a HDR skin applicator flatering filter” D. Granero, J. Perez-Calatayud,

J. Gimeno, F. Ballester, E. Casal, V. Crispin, R. van der Laarse. Med. Phys. 35(2) 495-503

(2008)

"Dosimetric evaluation of internal shielding in a high dose rate skin applicator" F. Lliso, D.

Granero, J. Perez-Calatayud, V. Carmona, Ma Carmen Pujades, F. Ballester. J. Contemp

Brachyther 3(1) 32-35 (2011)

"Correspondence: Reply to “Comments on “Correspondence factor for Nucletron surface

applicators”"”

D. Granero, J. Perez-Calatayud, F. Ballester, V. Crispin, E. Casal, J. Gimeno, R. vd Laarse Med

Phys 39(4) . 2310-2311 (2012)

"Radiation leakage study for the Valencia applicators" D. Granero, J. Perez-Calatayud, F.

Ballester, Z. Ouhib.

E. Journal Med. Phys. 29, 60-64 (2013)

"Dosimetric characteristics of a new unit for electronic skin brachytherapy" T. Garcia-Martinez,

J-P. Chan, J. Perez-Calatayud, F. Ballester J. Contemp Brachyther 6(1) 1-9 (2014)

"Non-melanoma skin cancer treated with HDR Valencia applicator: clinical outcomes" A. Tormo,

F. Celada, S. Rodriguez, R. Botella, A. Ballesta, M. Kasper, Z. Ouhib, M. Santos, J. Perez-

Calatayud..J. Contemp Brachyther 6(2) 167-172 (2014)

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References Valencia Group II

perez_jos@gva.es

"Clinical implementation of a new electronic brachytherapy system for skin brachytherapy" O.

Pons, R. Ballester, F. Celada, C. Candela, T. Garcia, M. Llavador, R. Botella, C. Barker, A.

Ballesta, A. Tormo, S. Rodriguez, J. Perez-Calatayud..J. Contemp Brachyther 6(4) 417-423

(2014)

"Depth determination of skin cancers treated with superficial brachytherapy: ultrasound vs

histopathology"

R. Ballester, O. Pons, M. Llavador, R. Botella, A. Ballesta, A. Tormo, F. Celada, S. Rodriguez,

M. Santos, F. Ballester, J. Perez-Calatayud. J. Contemp Brachyther 6(4) 417-423 (2014)

"Commissioning and periodic test of the Esteya electronic brachytherapy system" C. Candela-

Juan, Y. Niatsetski, Z. Ouhib, F. Ballester, J. Vijande, J. Perez-Calatayud.J. Contemp Brachyther

7(2) 189-195 (2015)

“Efficacy and safety of electronic brachytherapy for superficial and nodular basal cell

carcinoma“.R. Ballester, O. Pons, C. Candela-Juan, F. Celada, B. de Unamuno, M. Llavador, A.

Ballesta, C. Barker, A. Tormo, R. Botella, J. Perez-Calatayud. J. Contemp Brachyther 7(3) 1-8

(2015)

"Comparison and uncertainty evaluation of different calibration protocols and ionization

chambers for low-energy surface brachytherapy dosimetry”. C. Candela-Juan, J. Vijande, T.

García-Martínez, Y. Niatsetski, G. Nauta, J. Schuurman, Z. Ouhib, F. Ballester, and J. Perez-

Calatayud.. Med. Phys. 42 (2015) 4954-4964

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Thank you

perez_jos@gva.es