The invention relates to an acoustic probe for treating cancerous tissue, for introduction into a natural or surgically created cavity in the patient, in close proximity to a tissue area which includes cancerous cells. The probe includes an acoustic transmitter arranged for transmitting an acoustic signal having characteristics which causes damage of said cancerous cells and means for administering chemotherapeutic substances. The invention further relates to a corresponding method and a system for treating cancerous tissue. The use of the invention may be combined with the use of encapsulated cytostatica within micelles or therapeutic molecules.