Thoracic tumors treated with CT-guided radiofrequency ablation: initial experience.
OBJECTIVE
To determine the effectiveness of computed tomography (CT)-guided radiofrequency (RF) ablation of malignant thoracic tumors.


METHODS
CT-guided RF ablations of 99 malignant thoracic tumors (3-80 mm in largest diameter; mean, 19.5 mm) were performed in 35 patients in 54 sessions. Ablation was performed with an RF generator by using a single internally cooled electrode. Tumors were both primary (three lesions) and secondary (pulmonary or pleural metastases, 96 lesions). Follow-up was 1-17 months (mean, 7.1 months). Follow-up CT and histopathologic examinations were evaluated. Univariate analysis was performed with the Fisher exact test, and Welch t test was used to evaluate differences between group means. P <.05 represented a significant difference. The maximal diameter of each residual tumor or local recurrence or the proportion of primary lesions of pulmonary metastatic tumors with recurrence after RF ablation were analyzed. Complications, management, and outcomes of the complications were recorded.


RESULTS
The appearance of each ablation zone, including the target tumor and surrounding normal lung parenchyma, showed involution at follow-up CT. Local recurrence was demonstrated histopathologically or radiologically in nine tumors. The other 90 tumors showed no growth progression at follow-up CT. Probable complete coagulation necrosis obtained with initial RF ablation was achieved in 91% (90 of 99) of the tumors. The mean maximal diameter of the nine tumors (19.6 mm +/- 7.7 [SD]) was not significantly different (P =.994) from that of the other 90 tumors (19.5 mm +/- 13.0). Primary lesions of those nine metastatic tumors varied and did not demonstrate a specific tendency. Complications included pneumothorax, fever higher than 37.5 degrees C, hemoptysis, cough, pleural effusion, abscess formation, and hemothorax. The overall complication rate was 76% (41 of 54 sessions).


CONCLUSIONS
RF ablation seems to be a promising treatment for malignant thoracic tumors.
Yasui
Kotaro
K
Department of Radiology, Okayama University Medical School, Okayama Saiseikai General Hospital, 1-17-18 Ifuku-cho, Okayama 700-8511, Japan. yasui@saiseidr.jp
Kanazawa
Susumu
S
Sano
Yoshifumi
Y
Fujiwara
Toshiyoshi
T
Kagawa
Shunsuke
S
Mimura
Hidefumi
H
Dendo
Shuichi
S
Mukai
Takashi
T
Fujiwara
Hiroyasu
H
Iguchi
Toshihiro
T
Hyodo
Tsuyoshi
T
Shimizu
Nobuyoshi
N
Tanaka
Noriaki
N
Hiraki
Yoshio
Y
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017115:Catheter Ablation / Q000009:adverse effects; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000556:secondary / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D010997:Pleural Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D015641:Radiography, Interventional; D014057:Tomography, X-Ray Computed