Thermo-mechanical analysis of tumor-tissue during cryosurgery: a numerical study

Abstract: Since decades, many techniques have been developed for curing cancer. Here, an effort has been made to cure tumor by inserting a cryoprobe into the target region which is connected to a cryogenic mechanism. This technique is presently used only for curing simple tumors and hence the motive here is to trigger this technique towards curing large sized internal tumors. Thermo-mechanical study was done for the tumor-tissue subjected to cryotherapy using COMSOL Multiphysics software. A 3-D model has been presented considering all the properties to be a function of temperature. Phase transformation of bio liquid to ice was also considered in the study. Also, parametric study has been done by varying the probe and tumor dimensions and also by varying the tumor location. Pain tolerance of the tissue during this process was also studied. Variety of thermal and mechanical distributions have been extracted from the study which gave an idea about the time of operation, pain experience and the effect of process on the surrounding healthy tissue. It was found that, heat transfer and thermal stress in the tissue increased with increase in probe diameter and decrease in tumor size and reached a steady state at around 50 mins. Cryosurgery becomes simpler as the tumor moves out of the tissue. It was also predicted that the patient might experience severe pain by the end of treatment. This study might help researchers and surgeons in improving the understanding of cryosurgery process along with its limitations.