  Percutaneous thermal ablation is a minimally-invasive treatment option for
renal cancer. To treat larger tumours, multiple overlapping ablations zones are
required. Arrangements with a low number of ablation zones but coverage of the
whole tumour volume are challenging to find for physicians. In this work, an
open-source software tool with a new planning approach based on the automatic
selection from a large number of randomized geometrical arrangements is
presented. Two uncertainty parameters are introduced to account for tissue
shrinking and tolerance of non-ablated tumour volume. For seven clinical renal
T1a, T1b and T2a tumours, ablation plans were proposed by the software. All
proposals are comparable to manual plans of an experienced physician with
regard to the number of required ablation zones.
