Thermal analysis of a tumorous vascular tissue during pulsed-cryosurgery and nano-hyperthermia therapy: Finite element approach

It is well-known that a successful cell destruction is a time-temperature-dependent process, so that the less temperature and the more freezing time, the more cell death will occur successfully. Hence, in order to be more effective ablation, the cryosurgery, whenever needed, should be done in a longer term and at a lower temperature in a more precise, controlled manner. To achieve the goal of targeted cancer therapy, we have proposed a pulsed-cryosurgery as a simple and impressive planning framework to provide conditions for the ablation of deep tumors with minimum damaging impact on normal tissue. To do so, a 2D space-time-dependent model is developed with the help of the coupled Pennes' bio-heat, Navier-Stokes and Laplace equations to predict temperature distribution in the tumor, normal tissues and the microvascular network. Our results are in adequate harmony with the available ones in the literature. Furthermore, growing and shrinking of the ice-ball and lethal zone during and after the cryosurgery have been numerically studied. Subsequently, the effects of the heat generation produced by an electric field for hyperthermia treatment, the injection of nanofluid and spatial arrangement of cryoprobes on heat transfer in the biological tissues have been discussed. All the mentioned results have been supported and verified by illustrative simulations. (C) 2019 Elsevier Ltd. Ail rights reserved.