Abstract
Cryosurgery and hyperthermia treatment are used as a treatment method for malignant tumors. Since liquid nitrogen is used as the cryogens, it is difficult to control the freezing rate and thawing rate. In hyperthermia, there are problems of thermotolerance acquisition by heat shock protein (HSP) and only a few studies regarding hyperthermia with cryosurgery have been investigated. The aims of this study are to produce cryosurgery-hyperthermia system utilizing Stirling Cooler and Peltier device and evaluate hyperthermia after cryosurgery by comparing cryosurgery and hyperthermia on the mouse liver. Normal living liver tissues of mice are divided into 3 groups (cryosurgery and cryosurgery-hyperthermia, hyperthermia), then performed cryosurgery, hyperthermia and hyperthermia followed cryosurgery, applying a 1 cycle rapid freezing and slow thawing method for cryosurgery. The temperatures of the tissue surface and probe were measured during operation, the liver was stained by Hematoxylin-Eosin (HE) after operation and observed under an optical microscope. The results showed measured temperature of rapid freezing and slow thawing. HE stained tissue showed stasis, pyknosis, nucleus disappearance and decreasing stainability in cryosurgery and cryosurgery-hyperthermia group, stasis, pyknosis and degreasing stainability in hyperthermia group. The results suggested cryosurgery-hyperthermia was the most effective to destroy the tissue.
