The Study of Partial Microenvironment Pre- and Post-microwave Ablation in Rabbit Peripheral Pulmonary VX2 Tumors

Purpose: The aim of this study was to investigate the changes of CD3 and CD20 in the microenvironment of rabbit peripheral lung cancer before and after microwave ablation (MA). Methods: Twenty-four rabbits with lung VX2 tumor were randomly divided into four groups (n = 6 in each group). Ultrasound-guided MA was gone using 40 W powers as the treatment mode for about 60s. The animals were sacrificed by injecting anesthetic into the ear vein before and after MA. The thoracic ribs were cut off and the lung lobes were removed completely with tumor and then washed with saline. Part of the organization placed into 4% formaldehyde for pathological examination; part placed into 2.5% glutaraldehyde for the electron microscopy. Result: The histological features of ablation lesions showed as morphological abnormalities of tumor cells, cell and nuclear elongated by heat; the cells of alveolar wall degeneration and necrosis. The alveolar wall ruptured and alveolar structure disappeared. Blood cells and inflammatory cells appeared in the alveolar interstitial and a large number of serous exudated. The positive cell numbers of CD3 and CD20 cells at 2 weeks after MA were significantly different from those before MA and at 3 days and 1 week after MA (P< 0.01). There was no significant difference in the positive cells of CD3 and CD20 before and 3 days and 1 week after MA. Conclusion: The number of immune cells in tumor adjacent tissue increased significantly after MA and the level of local anti-tumor immune cells was also increased.