Predictive factors of diagnostic accuracy of CT-guided transthoracic fine-needle aspiration for solid noncalcified, subsolid and mixed pulmonary nodules

Purpose

The aim of this study was to analyse factors predicting the diagnostic accuracy of computed tomography (CT)-guided transthoracic fine-needle aspiration (TTFNA) for solid noncalcified, subsolid and mixed pulmonary nodules, with particular attention to those responsible for false negative results with a view to suggesting a method for their correction.

Materials and methods

From January 2007 to March 2010, we retrospectively reviewed the CT images of 198 patients of both sexes (124 males and 74 females; mean age, 70 years; range age, 44–90) used for the guidance of TTFNA of pulmonary nodules. Aspects considered were: lesion size and density, distance from the pleura, and lesion site. Multiplanar reformatted images (MPR) were retrospectively obtained in the sagittal and axial oblique planes relative to needle orientation.

Results

The overall diagnostic accuracy of TTFNA CTguided biopsy was 86% for nodules between 0.7 and 3 cm, 83.3% for those between 0.7 and 1.5 cm, and 92% for those between 2 and 3 cm. Accuracy was 95.1% for solid pulmonary nodules, 84.6% for mixed nodules, and 66.6% for subsolid nodules. The diagnostic accuracy of CT-guided TTFNA in relation to the distance between the nodule and the pleural plane was 95.6% for lesions adhering to the pleura and 83.5% for central ones. The diagnostic accuracy was 84.2% for the pulmonary upper lobe nodules, 85.3% for the lower lobe and 90.9% for those in the lingula and middle lobe. In 75% of false negative and inadequate/insufficient cases the needle was found to lie outside the lesion, after reconstruction of the needle path by MPR.

Conclusions

The positive predictive factors of CT-guided TTFNA are related to the nodule size, density and distance from the pleural plane. The most common negative predictive factor of CT-guided TTFNA is the wrong position of the needle tip, as observed in the sagittal and axial oblique sections of the MPR reconstructions. The diagnostic accuracy of CT-guided TTFNA can therefore be improved by using the MPR technique to plan the needle path during the FNA procedure.     

Ablative zone size created by radiofrequency ablation with and without chemoembolization in small hepatocellular carcinomas

Purpose

We retrospectively evaluated whether combined use of chemoembolization expands ablative zone sizes created by radiofrequency (RF) ablation in patients with small hepatocellular carcinomas (HCCs).

Materials and methods

Fifty-seven patients treated with single RF ablation for solitary HCC measuring ??2?cm were assessed. RF ablation alone was done in nine patients and in 48 patients following chemoembolization, with an interval of 0?days in 6, 1?C14?days in 27, 15?C28?days in 6, and ??4?weeks in 9. Ablative zone sizes, disappearance of tumor enhancement, and creation of sufficient ablative margins (>5?mm) were evaluated on contrast-enhanced computed tomography (CT) images.

Results

Both mean long-axis (4.2?C4.7 vs. 3.6?±?0.4?cm, p?p?p?Conclusion Ablative zones created by RF ablation with chemoembolization become larger than RF ablation alone, leading to secure ablative margins.     

Biplane fluoroscopy-guided radiofrequency ablation combined with chemoembolisation for hepatocellular carcinoma: initial experience

Objective

The purpose of this study was to assess the technical feasibility and local efficacy of biplane fluoroscopy-guided percutaneous radiofrequency (RF) ablation combined with transcatheter arterial chemoembolisation (TACE) for hepatocellular carcinoma (HCC).

Method

Our retrospective study was approved by the institutional review board and informed consent was waived. 18 patients with 19 HCCs (mean 2.5 cm diameter; range 2–4.2 cm) were treated with percutaneous RF ablation combined with TACE. After segmental TACE, 18 (95%) of 19 HCCs were visible on fluoroscopy. Shortly (median 2 days; range 1–4 days) after TACE, percutaneous RF ablation was performed under real-time biplane fluoroscopic guidance. We evaluated major complications, rate of technical success at immediate post-RF ablation CT images and local tumour progression at follow-up CT images.

Results

Major complication was not observed in any patients. Technical success was achieved for all 18 visible HCCs. During the follow-up period (median 20 months; range 5–30 months), no local tumour progression was found.

Conclusion

Biplane fluoroscopy-guided RF ablation combined with TACE is technically feasible and effective for treatment of HCC.Percutaneous radiofrequency (RF) ablation has been widely implemented in the management of hepatocellular carcinoma (HCC) with promising results. Although its local efficacy for small tumours (i.e. <2 cm) is similar to surgical outcomes [1], results for medium-sized and large tumours are less robust. Thus, multimodal treatments such as combined percutaneous RF ablation with transarterial chemoembolisation (TACE) have been explored for medium or large HCCs in order to enhance the therapeutic effect. In a recent study, RF ablation combined with TACE was similar to surgical resection in patients with early-stage disease [2].Percutaneous RF ablation shortly following TACE has been usually performed under guidance of either ultrasonography or CT/CT fluoroscopy. Since intratumoural retention of radio-opaque iodised oil induced by TACE conveniently provides radiographic contrast to the index lesion, biplane fluoroscopy (anterior posterior and lateral projections) can be used as an alternative guiding modality for RF ablation combined with TACE. Easier targeting of dome lesions, often difficult to visualise on ultrasound, through an oblique approach without pleural transgression is one potential advantage of biplane fluoroscopy guidance. Also unlike on ultrasound, microbubble formation during ablation would not obscure the index lesion on biplane fluoroscopy, allowing easier and more spatially accurate application of overlapping ablations that are often needed for larger tumours. However, to our knowledge, there have been no studies investigating the role of biplane fluoroscopy as a guidance modality in this clinical setting. The purpose of our study was to retrospectively assess the technical feasibility and local efficacy of biplane fluoroscopy-guided percutaneous RF ablation combined with TACE for HCC ≥2 cm.     

CT-guided Bipolar and Multipolar Radiofrequency Ablation (RF Ablation) of Renal Cell Carcinoma: Specific Technical Aspects and Clinical Results

Purpose

This study was designed to evaluate the clinical efficacy of CT-guided bipolar and multipolar radiofrequency ablation (RF ablation) of renal cell carcinoma (RCC) and to analyze specific technical aspects between both technologies.

Methods

We included 22 consecutive patients (3 women; age 74.2 ± 8.6 years) after 28 CT-guided bipolar or multipolar RF ablations of 28 RCCs (diameter 2.5 ± 0.8 cm). Procedures were performed with a commercially available RF system (Celon AG Olympus, Berlin, Germany). Technical aspects of RF ablation procedures (ablation mode [bipolar or multipolar], number of applicators and ablation cycles, overall ablation time and deployed energy, and technical success rate) were analyzed. Clinical results (local recurrence-free survival and local tumor control rate, renal function [glomerular filtration rate (GFR)]) and complication rates were evaluated.

Results

Bipolar RF ablation was performed in 12 procedures and multipolar RF ablation in 16 procedures (2 applicators in 14 procedures and 3 applicators in 2 procedures). One ablation cycle was performed in 15 procedures and two ablation cycles in 13 procedures. Overall ablation time and deployed energy were 35.0 ± 13.6 min and 43.7 ± 17.9 kJ. Technical success rate was 100 %. Major and minor complication rates were 4 and 14 %. At an imaging follow-up of 15.2 ± 8.8 months, local recurrence-free survival was 14.4 ± 8.8 months and local tumor control rate was 93 %. GFR did not deteriorate after RF ablation (50.8 ± 16.6 ml/min/1.73 m² before RF ablation vs. 47.2 ± 11.9 ml/min/1.73 m² after RF ablation; not significant).

Conclusions

CT-guided bipolar and multipolar RF ablation of RCC has a high rate of clinical success and low complication rates. At short-term follow-up, clinical efficacy is high without deterioration of the renal function.     

Percutaneous Radiofrequency Ablation of Hepatocellular Carcinomas Adjacent to the Gallbladder with Internally Cooled Electrodes: Assessment of Safety and Therapeutic Efficacy

Objective

The objective of this study was to evaluate the safety and therapeutic efficacy of percutaneous radiofrequency (RF) ablation for the treatment of hepatocellular carcinomas (HCCs) adjacent to the gallbladder with the use of internally cooled electrodes.

Materials and Methods

We retrospectively assessed 45 patients with 46 HCCs (mean size, 2.2 cm) adjacent to the gallbladder (≤1.0 cm) treated with RF ablation using an internally cooled electrode system. An electrode was inserted into the tumor either parallel (n = 38) or perpendicular (n = 8) to the gallbladder wall. The safety and therapeutic efficacy of the procedures were assessed with clinical and imaging follow-up examinations. Follow-up with the use of CT ranged from four to 45 months (mean, 19 months). The association between variables (electrode direction, electrode type, tumor size, tumor location, lobar location) and the presence of a residual tumor or local tumor progression was also analyzed.

Results

There were no major complications and minor complications were noted in three patients (7%) including one case of vasovagal syncope and two cases of bilomas. Wall thickening of the gallbladder adjacent to the RF ablation zone was noted in 14 patients (41%) as determined on immediate follow-up CT imaging. Wall thickening showed complete disappearance on subsequent follow-up CT imaging. The primary technique effectiveness rate was 96% (44/46) based on one-month follow-up CT imaging. Local tumor progression was noted in six (14%) of 44 completely ablated tumors during the follow-up period. The direction of electrode insertion (perpendicular), tumor size (≥3 cm) and tumor location (a tumor that abutted the gallbladder) were associated with an increased risk of early incomplete treatment. No variable was significantly associated with local tumor progression.

Conclusion

Percutaneous RF ablation of HCCs adjacent to the gallbladder using an internally cooled electrode is a safe and effective treatment. Significant risk factors that lead to early incomplete treatment include tumor size, tumor location and electrode direction.     

Role of Sonazoid-enhanced three-dimensional ultrasonography in the evaluation of percutaneous radiofrequency ablation of hepatocellular carcinoma

Objective

We investigated contrast-enhanced three-dimensional ultrasonography (CE 3D US) with contrast agent Sonazoid for evaluating the effect of percutaneous radiofrequency (RF) ablation of hepatocellular carcinomas (HCCs).

Methods

63 HCCs were treated by US-guided percutaneous RF ablation. CE 3D US after bolus injection of 0.2 mL of Sonazoid was performed 5-7 days before and 1 day after RF ablation. CE 3D computed tomography (CT) was performed 5-7 days before and 1 month after the ablation, and during the follow-up period. Multiplanar images in three orthogonal planes and US/CT angiograms were reconstructed on both modalities. Two blinded observers reviewed the images on both modalities to evaluate the ablation effects.

Results

After RF ablation, the evaluation on CE 3D US and that on CE 3D CT achieved concordance in 61 lesions. Among them, 59 lesions were detected with the absence of tumor vessels and tumor enhancement and evaluated as adequate ablation, and the remaining two lesions were detected with residual tumors. The kappa value for agreement between the findings on the two modalities was 0.65. When 1-month CE 3D CT scans were used as reference standard, the sensitivity, specificity, and accuracy of 1-day CE 3D US for detecting adequate ablation were 97%, 100%, and 97%, respectively.

Conclusion

By demonstrating the ablated areas and residual tumors in three dimensions, CE 3D US with Sonazoid was shown to be useful for evaluating the effect of RF ablation of HCCs, and there was good concordance with the results obtained by CE 3D CT.     

Lung Radiofrequency Ablation for the Treatment of Unresectable Recurrent Non-Small-Cell Lung Cancer After Surgical Intervention

Purpose

A retrospective evaluation was done of clinical utility of lung radiofrequency (RF) ablation in recurrent non-small-cell lung cancer (NSCLC) after surgical intervention.

Methods

During May 2003 to October 2010, 44 consecutive patients (26 male and 18 female) received curative lung RF ablation for 51 recurrent NSCLC (mean diameter 1.7?±?0.9?cm, range 0.6 to 4.0) after surgical intervention. Safety, tumor progression rate, overall survival, and recurrence-free survival were evaluated. Prognostic factors were evaluated in multivariate analysis.

Results

A total of 55 lung RF sessions were performed. Pneumothorax requiring pluerosclerosis (n?=?2) and surgical suture (n?=?1) were the only grade 3 or 4 adverse events (5.5%, 3 of 55). During mean follow-up of 28.6?±?20.3?months (range 1 to 98), local tumor progression was found in 5 patients (11.4%, 5 of 44). The 1-, 3-, and 5-year overall survival rates were 97.7, 72.9, and 55.7%, respectively. The 1- and 3-year recurrence-free survival rates were 76.7 and 41.1%, respectively. Tumor size and sex were independent significant prognostic factors in multivariate analysis. The 5-year survival rates were 73.3% in 18 women and 60.5% in 38 patients who had small tumors measuring ??3?cm.

Conclusion

Our results suggest that lung RF ablation is a safe and useful therapeutic option for obtaining long-term survival in treated patients.     

Image-guided radiofrequency ablation of hepatocellular carcinoma (HCC): Is MR guidance more effective than CT guidance?

Objectives

The purpose of the study was to retrospectively compare technique effectiveness of computed tomography (CT)-guided versus magnetic resonance (MR)-guided radiofrequency (RF) ablation of hepatocellular carcinoma (HCC).

Materials and methods

In 35 consecutive patients 53 CT-guided (n = 29) or MR-guided (n = 24) ablation procedures were performed in the treatment of 56 (CT: 29; MR: 27) HCC. The entire ablation procedure was performed at a multislice CT-scanner or an interventional 0.2-Tesla MR-scanner. Assessment of treatment response was based on dynamic MR imaging at 1.5 Tesla. The mean follow-up was 22.9 months. Primary technique effectiveness was assessed 4 months after ablation therapy. Secondary technique effectiveness was assessed 4 months after a facultative second ablation procedure. Primary and secondary technique effectiveness of CT-guided and MR-guided RF ablation was compared by using Chi-Square (likelihood ratio) test.

Results

Primary technique effectiveness after a single session was achieved in 26/27 (96.3%) HCC after MR-guided RF ablation and 23/29 (79.3%) HCC after CT-guided RF ablation (Chi-Square: p = 0.04). Secondary technique effectiveness was achieved in 26/27 (96.3%) HCC after MR-guided RF ablation and in 26/29 (89.7%) HCC after CT-guided RF ablation (Chi-Square: p = 0.32). A local tumor progression was detected in 8/52 (15.4%) tumors after initial technique effectiveness. Major complications were detected after 3/53 (5.7%) ablation procedures.

Conclusions

CT-guided and MR-guided RF ablations are locally effective therapies in the treatment of HCC. Due to a higher rate of primary technique effectiveness MR-guided RF ablation may reduce the number of required sessions for complete tumor treatment.     

Central lower attenuating lesion in the ablation zone on immediate follow-up CT after percutaneous radiofrequency ablation for hepatocellular carcinoma: Incidence and clinical significance

Purpose

The purpose of this study was to evaluate the incidence of central lower attenuating (CLA) lesion in the ablation zone seen on immediate follow-up CT images after percutaneous radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC), and the correlation of CLA lesions and local tumor progression (LTP).

Subjects and methods

The study group included 146 patients with 167 ablation zones that had undergone follow-up CT examinations for more than 12 months after percutaneous RFA. CLA lesions corresponding to index tumors and ablative margins (safety margins) were evaluated in the ablation zones seen on immediate follow-up CT including coronal and sagittal multiplanar reformatted (MPR) images with narrow window width settings.

Results

CLA lesions were depicted on 48 of 167 ablation zones (28.7%) on immediate follow-up CT images. Among the 48 ablation zones with CLA lesions, 27 (56.3%, 27/48) had ablative margins on all three of the orthogonal MPR images and they showed no LTP (0%) on follow-up CT examinations. Three of the ablation zones with CLA lesions (6.3%, 3/48) having an ablative margin on one plane only also showed no LTP (0%). LTP was observed in 2 of 18 ablation zones (11.1%) that had CLA lesions without ablative margins on all three planes. In the remaining 119 ablation zones without CLA lesions, 5 (4.2%, 5/119) showed LTP.

Conclusion

CLA lesions in ablation zones were occasionally (28.7%) seen on immediate follow-up CT images after RFA for HCCs. The presence of CLA lesions with ablative margins might be a negative predictor of LTP.     

Radiofrequency Ablation Combined with Chemoembolization for Intermediate-Sized (3-5 cm) Hepatocellular Carcinomas Under Dual Guidance of Biplane Fluoroscopy and Ultrasonography

Objective

To assess the technical feasibility and local efficacy of percutaneous radiofrequency ablation (RFA) combined with transcatheter arterial chemoembolization (TACE) for an intermediate-sized (3-5 cm in diameter) hepatocellular carcinoma (HCC) under the dual guidance of biplane fluoroscopy and ultrasonography (US).

Materials and Methods

Patients with intermediate-sized HCCs were treated with percutaneous RFA combined with TACE. RFA was performed under the dual guidance of biplane fluoroscopy and US within 14 days after TACE. We evaluated the rate of major complications on immediate post-RFA CT images. Primary technique effectiveness rate was determined on one month follow-up CT images. The cumulative rate of local tumor progression was estimated with the use of Kaplan-Meier method.

Results

Twenty-one consecutive patients with 21 HCCs (mean size: 3.6 cm; range: 3-4.5 cm) were included. After TACE (mean: 6.7 d; range: 1-14 d), 20 (95.2%) of 21 HCCs were visible on fluoroscopy and were ablated under dual guidance of biplane fluoroscopy and US. The other HCC that was poorly visible by fluoroscopy was ablated under US guidance alone. Major complications were observed in only one patient (pneumothorax). Primary technique effectiveness was achieved for all 21 HCCs in a single RFA session. Cumulative rates of local tumor progression were estimated as 9.5% and 19.0% at one and three years, respectively.

Conclusion

RFA combined with TACE under dual guidance of biplane fluoroscopy and US is technically feasible and effective for intermediate-sized HCC treatment.     

Effect of interval between transcatheter hepatic arterial embolization and radiofrequency ablation on ablated lesion size in a swine model

Purpose

The aim of the study was to clarify the effect of the interval between transcatheter hepatic arterial embolization (TAE) with Lipiodol plus gelatin sponge particles and radiofrequency (RF) ablation on the extent of ablation.

Materials and methods

Eight healthy swine were divided into four groups: RF ablation (ablation only), RF ablation immediately after TAE (immediate ablation), RF ablation 3 days after TAE (3-day ablation), and RF ablation 6 days after TAE (6-day ablation). Five ablated lesions were created in each swine (10 per group). A 2-cm expandable LeVeen needle electrode was used for RF ablation. Ablated lesions are composed of an outer reddish zone and an inner whitish zone.

Results

The average longest length of the major, intermediate, and minor axes and the volume in the immediate ablation, 3-day ablation, and 6-day ablation groups were significant longer and greater (1.52 and 1.52, 1.46 and 1.50, and 1.37 and 1.35 times greater in the red zone and the whitish area, respectively) than those in the ablation-only group (P < 0.05/3). Accumulation of Lipiodol was still noted in the hepatic sinusoids in the 3-day and 6-day ablation groups.

Conclusion

RF ablation delayed to 6 days following TAE produced larger ablation volumes than did RF ablation alone.     

MR-guided radiofrequency ablation using a wide-bore 1.5-T MR system: clinical results of 213 treated liver lesions

Objective

To evaluate the technical effectiveness, technical success and patient safety of MR-guided radiofrequency (RF) ablation of liver malignancies using a wide-bore 1.5-T MR system.

Methods

In 110 patients, 56 primary liver lesions and 157 liver metastases were treated in 157 sessions using percutaneous RF ablation. Mean lesion diameter was 20?mm (range 4–54?mm). All planning, procedural and post-interventional control MR investigations were carried out using a wide-bore 1.5-T MR system. Technical success was assessed by a contrast-enhanced MR liver examination immediately after the intervention. Technique effectiveness was assessed by dynamic hepatic MR study 1?month post ablation; mean follow-up period was 24.2?months (range 5–44).

Results

Technical success and technique effectiveness were achieved in 210/213 lesions (98.6?%). In 18/210 lesions (8.6?%), local tumour progression occurred 4–28?months after therapy. Seven of these 18 lesions were treated in a second session achieving complete ablation, 6 other lesions were referred to surgery. Overall RF effectiveness rate was 199/213 (93.4?%); overall therapy success (including surgery) was 205/213 (96.2?%). Two major complications (1.3?%) (bleeding and infected biloma) and 14 (8.9?%) minor complications occurred subsequent to 157 interventions.

Conclusion

Wide-bore MR-guided RF ablation is a safe and effective treatment option for liver lesions.

Key Points

? Magnetic resonance-guided radiofrequency ablation offers various options for monitoring therapy. ? All steps of RF ablation carried out in 1.5-T wide-bore system. ? Therapeutic decisions were based on T1-weighted imaging. ? Technical success and technical effectiveness were high. ? Local tumour progression rate was 8.6?% over a 24-month mean follow-up.     

Incidence of new foci of hepatocellular carcinoma after radiofrequency ablation: role of multidetector CT

Purpose

The authors sought to assess the incidence of new foci of hepatocellular carcinoma (HCC) using multidetector computed tomography (MDCT) in patients treated with radiofrequency ablation (RFA).

Materials and methods

Two readers retrospectively reviewed by consensus the follow-up MDCT studies of 125 patients (88 men and 37 women; mean age 68 years) with 141 HCCs (size 1?C5.2 cm; mean 2.2 cm) treated with RFA. MDCT follow-up was performed at 1 and 3 months and every 6?C12 months thereafter. Reviewers assessed: (1) the presence of new HCC foci in the same liver segment or in a different segment; (2) complete or incomplete tumour ablation; (3) tumour progression.

Results

A total of 113 new HCCs (size 0.7?C4.8 cm; mean 1.7 cm) were detected in 69/125 (55.2%) patients (mean follow-up 30.38±19.14 months). Of these, 86 (76.1%) new HCCs were multiple (p<0.0001), and 92 (81.4%) occurred in a different segment from that of the treated HCC (p<0.0001). New HCCs were observed in the first 12 months, between 12 and 24 months and after 24 months in 31/69 (44.9%), 24/69 (34.8%) and 14/69 (20.3%) patients, respectively (p=0.175). Mean diseasefree interval was 16.1±16.31 (range 1?C52) months. Complete tumour ablation was achieved in 132/141 (93.6%) treated HCCs, and tumour progression occurred in 29/141 (20.6%) cases.

Conclusions

In patients with RFA-treated HCCs, MDCT follow-up revealed a high incidence of new HCCs, even after 1 year of follow-up. The new foci tended to be multiple and located in a liver segment different from that of the previously treated nodules.     

Novel Percutaneous Radiofrequency Ablation of Portal Vein Tumor Thrombus: Safety and Feasibility

Purpose

We report our experience of the safety of partial recanalization of the portal vein using a novel endovascular radiofrequency (RF) catheter for portal vein tumor thrombosis.

Methods

Six patients with liver cancer and tumor thrombus in the portal vein underwent percutaneous intravascular radiofrequency ablation (RFA) using an endovascular bipolar RF device. A 0.035-inch guidewire was introduced into a tributary of the portal vein and through which a 5G guide catheter was introduced into the main portal vein. After manipulation of the guide catheter over the thrombus under digital subtraction angiography, the endovascular RF device was inserted and activated around the thrombus.

Results

There were no observed technique specific complications, such as hemorrhage, vessel perforation, or infection. Post-RFA portography showed partial recanalization of portal vein.

Conclusions

RFA of portal vein tumor thrombus in patients with hepatocellular carcinoma is technically feasible and warrants further investigation to assess efficacy compared with current recanalization techniques.     

Percutaneous radiofrequency ablation for patients with malignant lung tumors: a phase II prospective multicenter study (JIVROSG-0702)

Purpose

This prospective multicenter study aimed to evaluate the efficacy and safety of percutaneous radiofrequency (RF) ablation for lung cancer.

Materials and methods

From May 2008 to April 2012, 33 patients (26 men, 7 women; mean age 70.5 years) were enrolled. RF ablation was performed using an internally cooled or expandable multitined electrode. The primary endpoint was complete response (CR) determined using ¹⁸F fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) performed 6 months after RF ablation. The secondary endpoint was the incidence and grade of adverse events (AEs) evaluated using the Common Toxicity Criteria for Adverse Events, version 3.0.

Results

All patients underwent RF ablation and had efficacy analyses evaluated; however, FDG-PET/CT images before RF ablation were not available for two patients. The CR rate was 68 % (21 of 31 patients). One patient had a grade 5 AE unrelated to RF ablation. Grade ≥3 AEs occurred in 12 % of patients. During the follow-up period (median 37 months; range 1–55 months), five patients developed local tumor progression and nine (29 %) died. Overall survival at 1, 2, and 3 years was 97, 82, and 74 %, respectively.

Conclusion

Percutaneous RF ablation is a safe, feasible, and effective treatment for small malignant lung tumors.

     

Image-Guided Percutaneous Radiofrequency Ablation of Central Renal Cell Carcinoma: Assessment of Clinical Efficacy and Safety in 31 Tumors

Purpose

To assess clinical efficacy and safety of image-guided percutaneous radiofrequency (RF) ablation of central renal cell carcinoma with adjunctive pyeloperfusion.

Reproducibility of Abdominal Aortic Aneurysm Diameter Measurement and Growth Evaluation on Axial and Multiplanar Computed Tomography Reformations

Purpose

To compare different methods measuring abdominal aortic aneurysm (AAA) maximal diameter (Dmax) and its progression on multidetector computed tomography (MDCT) scan.

Materials and Methods

Forty AAA patients with two MDCT scans acquired at different times (baseline and follow-up) were included. Three observers measured AAA diameters by seven different methods: on axial images (anteroposterior, transverse, maximal, and short-axis views) and on multiplanar reformation (MPR) images (coronal, sagittal, and orthogonal views). Diameter measurement and progression were compared over time for the seven methods. Reproducibility of measurement methods was assessed by intraclass correlation coefficient (ICC) and Bland–Altman analysis.

Results

Dmax, as measured on axial slices at baseline and follow-up (FU) MDCTs, was greater than that measured using the orthogonal method (p?=?0.046 for baseline and 0.028 for FU), whereas Dmax measured with the orthogonal method was greater those using all other measurement methods (p-value range: <0.0001–0.03) but anteroposterior diameter (p?=?0.18 baseline and 0.10 FU). The greatest interobserver ICCs were obtained for the orthogonal and transverse methods (0.972) at baseline and for the orthogonal and sagittal MPR images at FU (0.973 and 0.977). Interobserver ICC of the orthogonal method to document AAA progression was greater (ICC?=?0.833) than measurements taken on axial images (ICC?=?0.662–0.780) and single-plane MPR images (0.772–0.817).

Conclusion

AAA Dmax measured on MDCT axial slices overestimates aneurysm size. Diameter as measured by the orthogonal method is more reproducible, especially to document AAA progression.     

Radiofrequency ablation for colorectal liver metastases: prognostic factors in non-surgical candidates

Purpose

To determine prognostic factors in patients with colorectal liver metastases who were not surgical candidates and received liver radiofrequency (RF) ablation.

Materials and methods

RF ablation was done for 141 colorectal liver metastases in 84 patients. There were 63 (75.0?%, 63/84) males and 21 (25.0?%, 21/84) females, with a mean age of 64.6?±?10.3. The mean maximum tumor diameter was 2.3?±?1.4?cm (range 0.5?C9.0?cm). Extrahepatic metastases were associated at the time of liver RF ablation in 23 patients (27.4?%, 23/84), and 12 (14.3?%, 12/84) had lung metastases considered controllable by planned lung RF ablation. Prognostic factors were evaluated by univariate and multivariate analyses.

Results

There was no procedure-related mortality. The 1-, 3-, and 5-year overall survival rates were 90.6?% (95?%CI, 83.9?C97.2?%), 44.9?% (95?%CI, 31.8?C57.9?%), and 20.8?% (95?%CI, 7.3?C34.3?%), respectively, with a median survival of 34.9?months. The univariate analysis showed that tumor diameter larger than 3?cm, tumor multiplicity, uncontrollable extrahepatic disease, and previous chemotherapy history were significantly worse prognostic factors. The former three factors remained significant for worse prognosis in the multivariate Cox model. Extrahepatic disease was not a prognostic factor when it could be controlled.

Conclusion

Tumor size and number, and uncontrollable extrahepatic metastases were significant prognostic factors.     

Computed Tomography-Guided Interstitial HDR Brachytherapy (CT-HDRBT) of the Liver in Patients with Irresectable Intrahepatic Cholangiocarcinoma

Purpose

This study was designed to investigate the clinical outcome of patients with irresectable, intrahepatic cholangiocarcinoma (IHC) treated with computed tomography (CT)-guided HDR-brachytherapy (CT-HDRBT) for local tumor ablation.

Method

Fifteen consecutive patients with histologically proven cholangiocarcinoma were selected for this retrospective study. Patients were treated by high-dose-rate internal brachytherapy (HDRBT) using an Iridium-192 source in afterloading technique through CT-guided percutaneous placed catheters. A total of 27 brachytherapy treatments were performed in these patients between 2006 and 2009. Median tumor enclosing target dose was 20?Gy, and mean target volume of the radiated tumors was 131 (±?90) ml (range, 10?C257?ml). Follow-up consisted of clinical visits and magnetic resonance imaging of the liver every third month. Statistical evaluation included survival analysis using the Kaplan?CMeier method.

Results

After a median follow-up of 18 (range, 1?C27) months after local ablation, 6 of the 15 patients are still alive; 4 of them did not get further chemotherapy and are regarded as disease-free. The reached median local tumor control was 10?months; median local tumor control, including repetitive local ablation, was 11?months. Median survival after local ablation was 14?months and after primary diagnosis 21?months.

Conclusion

In view of current clinical data on the clinical outcome of cholangiocarcinoma, locally ablative treatment with CT-HDRBT represents a promising and safe technique for patients who are not eligible for tumor resection.     

Benefits of 3D technique in guiding percutaneous retroperitoneal biopsies

Purpose

This study aimed to assess the usefulness and advantages of multiplanar reformations (MPR) during multidetector-row computed tomography (MDCT)-guided percutaneous fine-needle aspiration biopsy (FNAB) and core biopsy of retroperitoneal lesions that are difficult to access with the guidance of ultrasound and axial CT alone owing to overlying bony structures, large vessels or abdominal organs.

Materials and methods

MDCT-guided retroperitoneal FNAB and core biopsy was performed on 14 patients with suspected retroperitoneal neoplasm. We used MPR images (sagittal and coronal) obtained with a six-detector-row MDCT scanner and 20?C22 gauge Chiba needles.

Results

Using MDCT with 3D MPR allowed biological samples to be obtained in all cases (ten cytological and four histological) and diagnostic samples in 11/14 cases (78.5%). Histological samples were deemed adequate for diagnostic assessment in all cases and cytological samples in 7/10 cases (70%).

Conclusions

MPR images allowed sampling of retroperitoneal lesions until now considered unreachable with the guidance of axial MDCT alone. Compared with the conventional procedure, the use of MPR images does not increase the procedure time.