Minimally required heat doses for various tumour sizes in induction heating cancer therapy determined by computer simulation using experimental data

Purpose: Although induction heating cancer therapy (IHCT) using magnetic nanoparticles can be a promising approach to treatment-less multi-nodular cancers, the objective requirement for successful clinical application has not clearly been elucidated. We intended to define objective heat doses suitable for IHCT, especially focusing on the sizes of liver cancer nodules.Materials and methods: Alternating magnetic fields were applied to three human pancreatic cancer cell lines, the intercellular space of those cell pellets were filled with magnetic nanoparticles, and confirmed the cytotoxic effect of IHCT. Subsequently, the temperatures of liver cancer nodules in IHCT were simulated using a computer software program and the required heat dose for various sized tumours were determined.Results: Heating the cancer cells up to 50°C for 10 min was sufficient for complete cell killing and the heat dose of 1.7 W/gtumour is required for 10 mm tumour. Larger tumours require a smaller heat dose, e.g. 20 mm and 40 mm tu...