Radio-frequency tissue ablation of VX2 tumor nodules in the rabbit lung.
OBJECTIVE
The authors investigated whether small pulmonary malignancies could be treated with computed tomography (CT)-guided, percutaneously placed radio-frequency (RF) electrodes.


METHODS
Pulmonary tumors were created in 11 New Zealand white rabbits by using CT-guided injection of a VX2 sarcoma cell suspension into the lower portion of the right lung. Tumors were allowed to grow 14-21 days to achieve a diameter of 6-12 mm. Electrodes were placed coaxially into the tumors via insulated 19-gauge Turner needles. Seven tumors were treated with RF for 6 minutes at 90 degrees C. Four tumors served as controls and were not treated. Follow-up CT and histopathologic analysis were performed on days 0-28. Specimens from treated rabbits were examined histopathologically on days 0 and 3 (n = 2 each), and days 1, 5, and 28 (n = 1 each).


RESULTS
Immediately following treatment, CT images showed rounded opacities enveloping the tumor. This corresponded histologically to coagulation necrosis of tumor and surrounding alveoli. In all cases, at least 95% of treated tumor nodules were necrotic at histopathologic analysis. Peripheral residual nests of histologically viable tumor were seen in three rabbits (43%). Control rabbits showed growing tumor nodules without necrosis at autopsy (mean survival, 23 days after inoculation). Two RF-treated rabbits (29%) and one control rabbit (25%) had pneumothoraces.


CONCLUSIONS
Percutaneous RF tissue ablation can be used to successfully treat small parenchymal tumor nodules within the lung in an animal model.
Goldberg
S N
SN
Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA.
Gazelle
G S
GS
Compton
C C
CC
Mueller
P R
PR
McLoud
T C
TC
D000818:Animals; D017115:Catheter Ablation; D008168:Lung / Q000473:pathology / Q000601:surgery; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D009368:Neoplasm Transplantation; D011817:Rabbits; D014057:Tomography, X-Ray Computed