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

For decades, many techniques have been developed for curing cancer. Cryosurgery is one of such processes for destroying tumors by inserting a cryoprobe into the target region which is connected to a cryogenic mechanism. Presently, this technique is used only for curing simple tumors. Hence, this work aims to trigger this technique toward curing large-sized internal tumors. The main objectives of this work are (1) to identify the mechanical and thermal behavior of the tumor tissue by conducting a parametric study, (2) to analyze the pain sensation during this process and (3) to identify the constraints of this surgery technique. The whole study was done using COMSOL Multiphysics (TM) software. A 3-D model has been presented, considering all the properties to be a function of temperature. Also, the phase transformation bio-liquid to ice was considered in the study. Results showed the temperature and stress distributions in both tumors and surrounding healthy tissue under different operating conditions. 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 min. The results gave an idea about the time of operation, pain experience and the effect of cryosurgery on the surrounding healthy tissue. Treatment becomes simpler as the tumor moves out of the tissue. The threshold treatment period was predicted to be 50 min, after which patients could expect to experience severe pain. This study might help researchers and surgeons in improving the understanding of cryosurgery process along with its limitations.