ABSTRACT
<p><b>BACKGROUND</b>To observe the CT appearance and pathological changes of VX2 tumor in rabbit lung after radio-frequency ablation.</p><p><b>METHODS</b>After VX2 tumor tissue suspension was injected into the lungs, the transplanted lung cancer models were established in 36 New Zealand white rabbits. Twenty-eight rabbits were treated with radio-frequency ablation, and another 8 rabbits without any treatment as control. The CT appearances and pathological changes were observed in different time intervals after the treatment in 14 rabbits out of experimental group. The survival periods of the rabbits were recorded in the rest 14 rabbits of experimental group and the control group respectively.</p><p><b>RESULTS</b>Coagulative necrosis and cell apoptosis appeared in the tumor tissues after the ablation, and inflammatory cells were found in the lung tissues around the areas of ablation. Wadding shadows appeared in CT images after the treatment and disappeared with the inflammation vanished, but the tumor shadows ceased to increase. In the experimental group, tumor tissues were almost necrosed in the target areas of 21 rabbits, however, peripheral residual nests of histologically viable tumor were found in the target areas of the other 7 rabbits. The survival periods of rabbits in the experimental group and the control group were 38 days±3.4 days days and 26 days±2.8 days respectively (P < 0.05).</p><p><b>CONCLUSIONS</b>Radio-frequency ablation may be an effective method in the treatment of lung cancer.</p>
ABSTRACT
<p><b>BACKGROUND</b>To study the biological effects of multi-electrode radiofrequency ablation on pulmonary tissues of rabbits.</p><p><b>METHODS</b>Under the guidance of computer tomograph, electrodes were inserted into right lungs of New Zealand white rabbits and radiofrequency was performed. The biological effects were observed through CT image and microscopy.</p><p><b>RESULTS</b>Coagulative necrosis was found immediately in ablation area after the procedure. On the 7th postradiofrequency ablation day, fibrous tissues appeared in the necrotic lesions. On the 30th postradiofrequency ablation day, bronchial and alveolar epithelium began to proliferate. Within 60 to 90 days after treatments, the necrotic lesions were almost replaced by normal pulmonary tissues. In group with electrodes into the right hilum, time for treating and initial impedance were significantly different from those with electrodes into the peripheral sites of the right-lower lobes (P < 0.01, P < 0.01).</p><p><b>CONCLUSIONS</b>Multi-electrode radiofrequency ablation can be safely and effectivly performed in pulmonary tissue and cause coagulative necrosis within a certain extent.</p>