Evaluating the Impact of Cryoprobe Tip Structure for Effective Cryoablation of Breast Cancer

Abstract

This study aims to analyze the impact of the structure of a cryoprobe tip on the transient thermal phenomenon that takes place during cryoablation of breast cancer. A 2D axisymmetric breast model with an embedded tumor has been constructed using COMSOL Multiphysics® interface. Three different tip structures (conical, spherical, cylindrical) have been considered for the experimentation to determine the optimal shape which not only destroys a greater fraction of tumor volume with great rapidity but also ensures minimal damage to the neighboring healthy tissues. Fine triangular meshes have been generated all over the experimentation domain. The simulation has been performed for a duration of 200s employing Pennes bioheat equation with relevant thermo-physical properties of tissue layers and appropriate boundary conditions as well as initial conditions for each of the structure. From the result illustrated via the frozen fraction vs time plot, it can be deduced that despite having nearly same and comparable dimensions, the cylindrical probe tip, outperforms the conical and spherical tips by a margin of 13.57% and 7.44%, respectively in terms of destroying the tumor tissue volume. Therefore, the result shows that the probe tip with a greater surface area demonstrates better cryogenic activity which is in conformity with the expectation. In conclusion, the study delivers a significant insight for manufacturing especially engineered cryoprobe tip with adequate proof of concept and ushers a new pathway for enhancing the net efficacy of the cryosurgical intervention for the treatment of breast cancer. Still, the study offers scopes for further optimization to make it more realistic, effective and clinically relevant.