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 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 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 after- loading

Radium--Iridium

Manual and remote loading

LDR vs. HDR พารามิเตอร์ LDR HDR Dose rate < 2 Gy/ชั่วโมง Problem of radiation hazard + - Discomfort +++ Unexpect shift of applicators Ward Number of patient per day 1 มากกว่า 1 ราย Time for loading ชั่วโมง นาที Cost of machine

Manual or remote control afterloading 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 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

35

HR-CTV Bladder Rectum Sigmoid

D90 HR-CTV D2cc B D2cc R D2cc S

Chiang Mai

Breast cancer Polgar, 2009

Planning developments

Planning developments 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) /3D- CRT(38.5Gy) GEC-ESTRO working group trial (1170 pts enrolled) WBI 50 Gy plus boost 10 Gy versus HDR and PDR Pending for results 51

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 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 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