Transcript Research developments in brachytherapy

Technological advances in
Brachytherapy
Ekkasit Tharavichitkul, MD
The Division of Therapeutic Radiology
and Oncology, Faculty of Medicine,
Chiang Mai University
History
• Greek word = short
–Interstitial brachytherapy
–Contact brachytherapy
→ surface mould BT
→ intracavitary BT
→ endolumina BT
Brachytherapy history
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1896: Becquerel
1898: MarieSklodowska-Curie
1901: Danlosand Block: Paris
1905Abbe: US Radium implantations
• Different empirical methods and rules
•Stockholm method for Gyne (1914)
•Paris method for Gyne (1919)
•Manchester system (1934) Paterson-Parker,
Meredith
•Paris System for IS : Pierquin, Chassagne,
Dutreix
• Discovery of artificial radioactive isotopes
• 1934 Irene Curie -FrédericJoliot
• 1958 Iridium-I92: U. Henschke
• Development of afterloading concept
• 1958 -65 U. Henschke-D. Chassagne
• Developmentof 3D dosimetry and fundamental rules of
dosimetry
• 1965 B. Pierquin-D. Chassagne-A. Dutreix
Brachytherapy
Developments in BT
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Source and loading methods
Imaging developments
Applicator developments
Planning developments
Clinical research developments
Source and loading method
Radioisotope sources
and loading methods
• From Radium --- Iridium
• From LDR --- HDR --- PDR
• From manual loading to remote afterloading
Radium--Iridium
Manual and remote loading
LDR vs. HDR
พารามิเตอร ์
LDR
HDR
< 2 Gy/ชวั่ โมง
>12 Gy/ชวั่ โมง
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Unexpect shift of
applicators
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Ward
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Number of patient per
day
1
มากกว่า 1 ราย
Time for loading
ชัว
่ โมง
นาที
Cost of machine
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+++
Dose rate
Problem of radiation
hazard
Discomfort
• Manual or remote control afterloading
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Gynecological applicators
Guide needles: straight and curved
Plastic tubes
Moulds
Hypodermic needles
Silk wires
Endo-luminal catheters
• Remote control afterloaders
Imaging
Imaging developments
• Modern imagingtechniques:
-US, CT, MRI
• 3D dosimetry
-More accurate dose distribution
-DVH relation to outcome for target + OAR
X-ray base
Ultrasound guidance
U/S guidance
Applicators
Applicator developments
• More compatible with imaging
• CT/MR applicator
• Gynecological cancers
• Plastic catheter
• Breast cancer
• Prostate cancer
Standard applicators
Nucletron.com
Scatter; metallic applicator
CT/Applicator
Breast BT
mammosite
Multicatheter
Clearpath
Polgar, 2009
Volume concepts
Volume concepts
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1985 ICRU 38 :Gynecological brachytherapy
1997 ICRU 58 :Interstitial and intraluminal brachytherapy
2000 GEC-ESTRORec: Prostate Permanent Implants
2001 GEC-ESTRO Rec: Endovascular brachytherapy
2005 GEC-ESTRORec: Prostate Temporary Implants
2005 GEC-ESTRORec: 3D-GYNE
Ultrasound
CTV prostate
GEC-ESTRO handbook,2002
Target volume: HDR
Volume concepts of cervix
CHM, 2005
Diagram of CTVs
•HR-CTV
•Bladder
•Rectum
•Sigmoid
D90 HR-CTV
D2cc B
D2cc R
D2cc S
Chiang Mai
Breast cancer
Polgar, 2009
Planning
developments
Planning developments
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Shifting from 2D to 3D
Target volume definition
Algorithm: AAPM TG43 to Monte Carlo
Inverse planning
• IPSA (Inverse Planning Simulated Annealing)
• HIPO (the Hybrid Inverse Planning and
Optimization)
Clinical studies
Cervix
Breast BT
Polgar, 2009
Clinical studies
EVL, Estro course 2008
Toxicity profile
Niehoff
Clinical developments
All RCTs
NSABP B-39/RTOG 0413 (4800 pts enrolled)
 WBI 50 Gy plus boost to 60-66 Gy versus
Multicatheter (34Gy)/Mammosite(34 Gy) /3DCRT(38.5Gy)
GEC-ESTRO working group trial (1170 pts
enrolled)
 WBI 50 Gy plus boost 10 Gy versus HDR and PDR
Pending for results
Conclusions
• Modern brachytherapy which is high Ballistic selectivity and
adaptivity is a competitive tool in the multidisciplinary
treatment of cancer patients
• A strong collaboration between
-Radiation oncologists
-Organ specialists
-Medical physicists
-Radiation technologists
is necessary to obtain optimal results for the patient(s)
Our researches: CT
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From July 2008 - Dec 2009
16 pts in CT-based planning in EBRT and BT
BT 6.5 Gy x Fx
GEC-ESTRO recommendations concepts
Image-guided planning (optimized plan)
can reduced the dose to the bladder and
sigmoid colon with compromised dose to
the target
Our research:MRI
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From Feb 2009- nowadays
Planned 14 pts will be enrolled
MRI guided treatment: Dx, 1st BT, after
treatment
With GEC-ESTRO recommendations
Now 6 patients finished
Pending results