A method of treatment, clinical treatment assembly, robotic manipulator and controlling arrangements for the treatment of cancers are described. The invention has particular application in the treatment of breast cancer. A robotic manipulator (18) carries a jig assembly (30). The jig assembly (30) includes an array of treatment probes (52, 54, 56) and a single identification / diagnostic probe (58). The probes can be moved by the robotic manipulator (18) in three directions (x, y, θ). A subject breast tissue is received in a tank (16) through an operating window (14), and the robotic manipulator (18) is to firstly determine the site of a tumour in the breast tissue. Once the tumour has been located by use of the identification / diagnostic probe (58), the treatment probes (52, 54, 56) are used to ablate the tumour by the superposition of ultrasonic waves at a focal region. A series of such lesions may be performed in sequence to traverse the full extent of the tumour.