Effects and risks of radiofrequency ablation on the pulmonary tissue and vascular system: a preliminary histological study.

PURPOSE

Radiofrequency ablation (RFA) is one of the minimally invasive therapeutic modalities for malignant tumors. However, the effects and risks associated with RFA on pulmonary tumors have not yet been well investigated. We pathologically examined the effects of RFA on the healthy pulmonary parenchyma in the inflated and deflated states of swine lungs.

METHODS

We used two 2-year-old female pigs. Under general anesthesia, RFA was performed twice.

RESULTS

The mean duration of cauterization for the inflated lungs (93.0 +/- 65.4 s) was significantly shorter than that for the deflated lungs (390.3 +/- 75.6 seconds) (P = 0.0062). Histologically, the dilatation and congestion of the microvessels were more marked in the lungs. However, no histopathological differences were noticed between the inflated and deflated lungs. Adventitial degeneration was seen in the small vessels, but not in the wall of the large vessels.

CONCLUSIONS

This study confirmed, pathologically, that RFA is effective with an acceptable degree of minimal damage to the normal lung tissue, irrespective of its conditions, i.e., inflated or deflated, and can be safely done near the pulmonary vessels. Therefore, RFA appears to be a promising therapeutic strategy to control local lesions in the field of thoracic surgery.