Hyperthermia Applicator for Small Superficial Tumour Treatment Paolo TOGNI 1,Jan VRBA 1, Luca VANNUCCI 2 1 Dept. of EM Field, Czech Technical University in Prague 2 Dept.of Immunology, Institute of Microbiology, Academy of Sciences of Czech Republic

2 Outline Introduction on experimental research Applicator design description Computer Simulation optimization Experimental evaluation In-vivo experiments Conclusions

Research Microwave Hyperthermia as anti-cancer treatment Study morphological changes induced in superficial layers Immunological responses Melanoma in animal model

4 Model Characteristics Small tumour dimensions: diameter mm Limited deepness: around 10 mm Small animal body Subcutaneous Applicator Requirement Focused Heating Limited E-field penetration depth Superficial Cooling

5 Applicator Design (I) Planar Structure Squared resonant cavity Circular Slot-line radiating aperture Working Frequency 2450 MHz (ISM) Agar Phantom Water Bolus Planar Applicator

Applicator Design (II) Coaxial cable feeding Just TM mode can be excited Dominat Mode TM 110

S 11 Parameter Evaluation Opimized using Computer simulator:  Cavity dimensions  Slot line aperture Width Vector analzyer measurements:  Low Bolus thikness dependent  High contact dependent  Integrated bolus needed

SAR distribution inside phantom Low Penetration Depth

SAR distribution on phantom surface Tumour covering depends on bolus thickness 20 mm optimal thickness for our mouse model

Temperature distribution measurements IR Camera measurement: Limited Temperature penetration Better results expected on animal model for the effect of blood perfusion Without Water Bolus

Temperature distribution measurements IR Camera measurement: Effective Superficial cooling Reduced temperature penetration depth 70 mm 6 mm With Water Bolus

System for Hyperthermia

In-vivo Experiments Proper tumour temperature during treatment Proper tumour temperature during treatment Suitable skin cooling Suitable skin cooling Limited body temperature enhancement during treatment Limited body temperature enhancement during treatment

Conclusion Applicator suitable to treat small superficial tumours Suitable tumour covering Reduced enhancement of body temperature expected Suitable to used on surfaces with complex contour Perspective of clinical practice also in array configuration

Acknowledgements: This study is funded by the Grant Agency of the Academy of Sciences of the Czech Republic IAA , Institutional Research Concepts No. AV0Z and by the Grant Agency of the Czech Republic, Grant No.102/08/H081 Thank you for your attention!