This disclosure relates to an in vivo treatment of a skin lesion of a mammal comprising application of electrical energy to the skin lesion in a form of electrical pulses. At least one electrical pulse is applied. The pulse duration may be at least 1 nanosecond at the full-width-half-maximum. Surface of a tissue surrounding the skin lesion may be marked to guide the device to deliver the electric pulses at substantially precise locations on the lesion surface. This treatment may prevent at least growth of the lesion.
