Radiation Therapy combined with Pulsed Electric Field - A new efficient ffi i t tumor t t t treatment t modality d lit
Bertil R. Persson1,
[email protected] Catrin Bauréus Koch1,2, Gustav Grafström1, 1, Crister Ceberg Per Engström g g1 Henrietta Nittby2, Bengt Widegren3 Leif G. Salford2,
1Medical
Radiation Physics, 2Dept of Neurosurgery, 3Dept of Tumor Immunology
Lund University Lund Lund, Sweden, Sweden
Aim of the study y Study the therapeutic effect of treatment subcutaneously implanted glioma N32 tumours on male rats of the Fischer-344 Fischer 344 strain on the thigh with
Pulsed Electric Fields (PEF) in combination with
Radiation di i therapy h (RT) ( )
El-pulse treatment of subcutaneous rat glioma tumors in combination with radiation therapy El Pulse Treatment: 16 pulses of 1300 Volt/cm, 1.0 ms duration, 1 pulse per second
given immediately followed by or prior i to t
Radiation Treatment: 5 Gy Co-60 gamma radiation
Both Treatments repeated on 4 consecutive days
Exponential Growth of N32 Tumors implanted in the back leg of Rats 1600 1400
1000 800 600 400 200
Day of ffirst treatment
Tumor size / mm
2
1200
Controls C t l Radiation Therapy (RT) Pulsed El. Field (PEF) PEF + RT RT + PEF Exponential fit fo data
0
15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105
Time after inoculation / days
Survival after Combined treatment radiation prior/after High Voltage Pulses 100
Perce ent surviv vors / %
80
Combined treatment Radiation prior/after High Voltage Pulses
60
40
20
Exp.3 Controls Exp.3a 4*(5 Gy + HVIT) Exp.3b p 3b 4*(HVIT ( + 5 Gy)
Treatment 4 days 0 0
20
40
60
80
Time after inoculation / days
100
Tumor growth rate “TGR” TGR is estimated from the tumor volume measurements of each tumour fitted to a model of exponential growth. The tumor volume growth rate is thus defined according to the following equation. TV TGR G V ; dt where TV TGR
TV TV0 eTGRt
Tumour volume Tumour ggrowth rate constant day y-1
TGR Summary of 4 equal experimental series
24
22
