Determinants of Local Progression After Computed Tomography-Guided Percutaneous Radiofrequency Ablation for Unresectable Lung Tumors: 9-Year Experience in a Single Institution

Abstract

The purpose of this study was to retrospectively determine the local control rate and contributing factors to local progression after computed tomography (CT)-guided radiofrequency ablation (RFA) for unresectable lung tumor. This study included 138 lung tumors in 72 patients (56 men and 16 women; age 70.0 +/- 11.6 years (range 31-94); mean tumor size 2.1 +/- 1.2 cm [range 0.2-9]) who underwent lung RFA between June 2000 and May 2009. Mean follow-up periods for patients and tumors were 14 and 12 months, respectively. The local progression-free rate and survival rate were calculated to determine the contributing factors to local progression. During follow-up, 44 of 138 (32%) lung tumors showed local progression. The 1-, 2-, 3-, and 5-year overall local control rates were 61, 57, 57, and 38%, respectively. The risk factors for local progression were age (>or=70 years), tumor size (>or=2 cm), sex (male), and no achievement of roll-off during RFA (P < 0.05). Multivariate analysis identified tumor size >or=2 cm as the only independent factor for local progression (P = 0.003). For tumors <2 cm, 17 of 68 (25%) showed local progression, and the 1-, 2-, and 3-year overall local control rates were 77, 73, and 73%, respectively. Multivariate analysis identified that age >or=70 years was an independent determinant of local progression for tumors <2 cm in diameter (P = 0.011). The present study showed that 32% of lung tumors developed local progression after CT-guided RFA. The significant risk factor for local progression after RFA for lung tumors was tumor size >or=2 cm.

Percutaneous Cryoablation for the Treatment of Primary and Metastatic Lung Tumors: Identification of Risk Factors for Recurrence and Major Complications

“…Alternatively, this difference in size threshold could be due to the higher incidence of metastatic tumors in the study by Yashiro et al or differences in cryoprobe sizes, although both the study by Yashiro et al (4) and the present study used the Endocare system. Previous work on RF ablation also established larger tumor size as a risk factor for local progression, although some studies report a 2-cm threshold (17,18), and another reported a 3-cm threshold (19). In contrast to the study by Yashiro et al (4), this study did not find that proximity to a large vessel (diameter 4 3 mm) was predictive of local progression.…”

Simultaneous Computed Tomography-Guided Biopsy and Radiofrequency Ablation of Solitary Pulmonary Malignancy in High-Risk Patients

“…Pneumothorax during or subsequent to RFA in this series was also in line with the reported rates in the literature [14,21] and had no impact on local recurrences as well. Furthermore, as a major complication, we observed a single hemothorax with the bleeding originating from the RF-probe insertion into the middle lobe.…”

Lung radiofrequency and microwave ablation: a review of indications, techniques and post-procedural imaging appearances

“…60 Signs of relapse can be very subtle, particularly on early followup CT. Any change in lesion contour, increase in volume or contrast enhancement after 6 months is highly suspicious (Figures 8 and 9); however, there are no well-defined criteria to assess post-ablation appearances on CT. A recent study has described the following features as being most useful: a change in dynamic enhancement (increasing contrast material uptake in the ablation zone, nodular enhancement measuring .10 mm, any central enhancement .15 HU and enhancement greater than baseline at any time after ablation) and growth of the treatment zone after 3 months, peripheral nodular growth and change from GGO to solid opacity. 61 Modalities other than CT have been used to follow up ablated tumours.…”