Reduced Growth Rate of Tumors from Melanoma B16 Cells Exposed to Focused Shock Waves

We have developed a generator of two successive shock waves focused to a common focal point. Amplitude of the pressure waves reaches up to 100 MPa at the focus and the rarefaction waves of 25 MPa in amplitude produce cavitations. Schlieren photography of the focal region has demonstrated that interaction of the two successive shocks results in creation of a very complex pressure field at the focus and in creation of many secondary spherical short wavelength shocks originated in collapsing cavitations. Measurements of waveforms by the PVDF shock gauges at the focus indicated that the second wave is strongly attenuated with the increasing time delay between the shocks. Suspension of the melanoma cells B16 has been exposed to 150 and 600 of focused shock waves. Afterwards the cells have been inoculated to the inbred mice C57B16. Volume of the tumors growing from the exposed cells has been compared for 50 days with the tumors growing from the non exposed cells. We have demonstrated that the exposure of the melanoma B16 cells to the focused shock waves results in a reduced growth rate of the tumors. The reduced growth rate has been observed in both the 150 and 600 shocks trials, however, for the case of 600 shocks it was much more pronounced