Radiofrequency Ablation for Viable Hepatocellular Carcinoma around Retained Iodized Oil after Transcatheter Arterial Chemoembolization: Usefulness of Biplane Fluoroscopy Plus Ultrasound Guidance

Objective

To assess the technical feasibility and local efficacy of biplane fluoroscopy plus US-guided percutaneous radiofrequency ablation (RFA) for viable hepatocellular carcinoma (HCC) around retained iodized oil after transcatheter arterial chemoembolization (TACE).

Materials and Methods

Our prospective study was approved by our institutional review board and informed consent was obtained from all participating patients. For patients with viable HCC around retained iodized oil after TACE, biplane fluoroscopy plus US-guided RFA was performed. We evaluated the rate of technical success and major complications on a post-RFA CT examination and local tumor progression with a follow-up CT.

Results

Among 40 consecutive patients, 19 were excluded due to one of the following reasons: poorly visible HCC on fluoroscopy (n = 13), high risk location (n = 2), RFA performed under monoplane fluoroscopy and US guidance (n = 2), and poorly identifiable new HCCs on US (n = 2). The remaining 21 patients with 21 viable HCCs were included. The size of total tumors ranged from 1.4 to 5.0 cm (mean: 3.2 cm) in the longest diameter. Technical success was achieved for all 21 HCCs, and major complications were observed in none of the patients. During the follow-up period (mean, 20.3 months; range, 6.5-29.9 months), local tumor progression was found in two patients (2/21, 9.5%). Distant intrahepatic metastasis developed in 76.2% (16/21) of patients.

Conclusion

When retained iodized oil around the tumor after TACE hampers the targeting of the viable tumor for RFA, biplane fluoroscopy plus US-guided RFA may be performed owing to its technical feasibility and effective treatment for viable HCCs.     

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.     

Pretreatment Evaluation with Contrast-Enhanced Ultrasonography for Percutaneous Radiofrequency Ablation of Hepatocellular Carcinomas with Poor Conspicuity on Conventional Ultrasonography

Objective

To determine whether pretreatment evaluation with contrast-enhanced ultrasonography (CEUS) is effective for percutaneous radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) with poor conspicuity on conventional ultrasonography (US).

Materials and Methods

This retrospective study was approved by the institutional review board and informed consent was waived. From June 2008 to July 2011, 82 patients having HCCs (1.2 ± 0.4 cm) with poor conspicuity on planning US for RFA were evaluated with CEUS prior to percutaneous RFA. We analyzed our database, radiologic reports, and US images in order to determine whether the location of HCC candidates on planning US coincide with that on CEUS. To avoid incomplete ablation, percutaneous RFA was performed only when HCC nodules were identified on CEUS. The rate of technical success was assessed. The cumulative rate of local tumor progression was estimated with the use of the Kaplan-Meier method (mean follow-up: 24.0 ± 13.0 months).

Results

Among 82 patients, 73 (89%) HCCs were identified on CEUS, whereas 9 (11%) were not. Of 73 identifiable HCCs on CEUS, the location of HCC on planning US corresponded with that on CEUS in 64 (87.7%), whereas the location did not correspond in 9 (12.3%) HCCs. Technical success was achieved for all 73 identifiable HCCs on CEUS in a single (n = 72) or two (n = 1) RFA sessions. Cumulative rates of local tumor progression were estimated as 1.9% and 15.4% at 1 and 3 years, respectively.

Conclusion

Pretreatment evaluation with CEUS is effective for percutaneous RFA of HCCs with poor conspicuity on conventional US.     

Percutaneous Radiofrequency Ablation with Multiple Electrodes for Medium-Sized Hepatocellular Carcinomas

Objective

To prospectively evaluate the safety and short-term therapeutic efficacy of switching monopolar radiofrequency ablation (RFA) with multiple electrodes to treat medium-sized (3.1-5.0 cm), hepatocellular carcinomas (HCC).

Materials and Methods

In this prospective study, 30 patients with single medium-sized HCCs (mean, 3.5 cm; range, 3.1-4.4 cm) were enrolled. The patients were treated under ultrasonographic guidance by percutaneous switching monopolar RFA with a multichannel RF generator and two or three internally cooled electrodes. Contrast-enhanced CT scans were obtained immediately after RFA, and the diameters and volume of the ablation zones were then measured. Follow-up CT scans were performed at the first month after ablation and every three months thereafter. Technical effectiveness, local progression and remote recurrence of HCCs were determined.

Results

There were no major immediate or periprocedural complications. However, there was one bile duct stricture during the follow-up period. Technical effectiveness was achieved in 29 of 30 patients (97%). The total ablation time of the procedures was 25.4 ± 8.9 minutes. The mean ablation volume was 73.8 ± 56.4 cm³ and the minimum diameter was 4.1 ± 7.3 cm. During the follow-up period (mean, 12.5 months), local tumor progression occurred in three of 29 patients (10%) with technical effectiveness, while new HCCs were detected in six of 29 patients (21%).

Conclusion

Switching monopolar RFA with multiple electrodes in order to achieve a sufficient ablation volume is safe and efficient. This method also showed relatively successful therapeutic effectiveness on short-term follow up for the treatment of medium-sized HCCs.     

Transcatheter Arterial Chemoembolization for Infiltrative Hepatocellular Carcinoma: Clinical Safety and Efficacy and Factors Influencing Patient Survival

Objective

To evaluate the safety and efficacy of transcatheter arterial chemoembolization (TACE) in patients with infiltrative hepatocellular carcinoma (HCC) and to identify the prognostic factors associated with patient survival.

Materials and Methods

Fifty two patients who underwent TACE for infiltrative HCC were evaluated between 2007 and 2010. The maximum diameter of the tumors ranged from 7 cm to 22 cm (median 15 cm). Of 46 infiltrative HCC patients with portal vein tumor thrombosis, 32 patients received adjuvant radiation therapy for portal vein tumor thrombosis after TACE.

Results

The tumor response by European Association for the Study of the Liver criteria was partial in 18%, stable in 47%, and progressive in 35% of the patients. The median survival time was 5.7 months (Kaplan-Meier analysis). The survival rates were 48% at six months, 25% at one year, and 12% at two years. In the multivariable Cox regression analysis, Child-Pugh class (p = 0.02), adjuvant radiotherapy (p = 0.003) and tumor response after TACE (p = 0.004) were significant factors associated with patient survival. Major complications occurred in nine patients. The major complication rate was significantly higher in patients with Child-Pugh B than in patients with Child-Pugh A (p = 0.049, χ² test).

Conclusion

Transcatheter arterial chemoembolization can be a safe treatment option in infiltrative HCC patients with Child Pugh class A. Child Pugh class A, radiotherapy for portal vein tumor thrombosis after TACE and tumor response are good prognostic factors for an increased survival after TACE in patients with infiltrative HCCs.     

Radiofrequency Ablation Combined with Transcatheter Arterial Chemoembolization for the Treatment of Single Hepatocellular Carcinoma of 2 to 5 cm in Diameter: Comparison with Surgical Resection

Objective

To compare the effectiveness of radiofrequency ablation (RFA) combined with transcatheter arterial chemoembolization (TACE) with surgical resection in patients with a single hepatocellular carcinoma (HCC) ranging from 2 to 5 cm.

Materials and Methods

The study participants were enrolled over a period of 29 months and were comprised of 37 patients in a combined therapy group and 47 patients in a surgical resection group. RFA was performed the day after TACE, and surgical resection was performed by open laparotomy. The two groups were compared with respect to the length of hospital stay, rates of major complication, and rates of recurrence-free and overall survival.

Results

Major complications occurred more frequently in the surgical resection group (14.9%) than in the combined therapy group (2.7%). However, there was no statistical significance (p = 0.059). The rates of recurrence-free survival at 1, 2, 3 and 4 years were similar between the combined therapy group (89.2%, 75.2%, 69.4% and 69.4%, respectively) and the surgical resection group (81.8%, 68.5%, 68.5% and 65%, respectively) (p = 0.7962, log-rank test). The overall survival rates at 1, 2, 3 and 4 years were also similar between groups (97.3%, 86.5%, 78.4% and 78.4%, respectively, in the combined therapy group, and 95.7%, 89.4%, 84.3% and 80.3%, respectively, in the surgical resection group) (p = 0.6321, log-rank test).

Conclusion

When compared with surgical resection for the treatment of a single HCC ranging from 2 to 5 cm, RFA combined with TACE shows similar results in terms of recurrence-free and overall survival rates.     

Therapeutic Efficacy and Safety of Percutaneous Ethanol Injection with or without Combined Radiofrequency Ablation for Hepatocellular Carcinomas in High Risk Locations

Objective

To evaluate the therapeutic efficacy and safety of percutaneous ethanol injection (PEI) alone and combined with radiofrequency ablation (RFA) for hepatocellular carcinomas (HCCs) in high risk locations.

Materials and Methods

We performed PEI for HCCs in RFA-high risk locations, either alone or in combination with RFA. There were 20 HCCs (1.7 ± 0.9 cm) in 20 patients (PEI group: n = 12; PEI + RFA group: n = 8). We evaluated technical success, local tumor progression and complications in both groups.

Results

Technical success was achieved in all HCCs in both groups. During follow-up, local tumor progression was found in 41.7% (5/12) in the PEI group, whereas 12.5% (1/8) for the PEI + RFA group (p = 0.32). Bile duct dilatation was the most common complication, especially when the tumors were in periportal locations; 55% (5/9) in the PEI group and 50% (2/4) in the PEI + RFA group (p = 1.00). One patient in the PEI group developed severe biliary stricture and upstream dilatation that resulted in atrophy of the left hepatic lobe. One patient treated with PEI + RFA developed cholangitis and an abscess.

Conclusion

Combined PEI and RFA treatment has a tendency to be more effective than PEI alone for managing HCCs in high risk locations, although the difference is not statistically significant. Even though PEI is generally accepted as a safe procedure, it may cause major biliary complications for managing HCCs adjacent to the portal vein.     

Hepatocellular carcinomas 2-3 cm in diameter: transarterial chemoembolization plus radiofrequency ablation vs. radiofrequency ablation alone

Objective

There is debate whether transarterial chemoembolization (TACE) plus radiofrequency ablation (RFA) is more effective than RFA alone in the treatment of patients with small hepatocellular carcinoma (HCC). We therefore retrospectively compared these treatments in patients with HCCs of diameter 2–3 cm.

Materials and methods

Outcomes, including tumor progression, survival rates, and major complications, were compared in 83 patients (83 tumors) treated with combined TACE and RFA and in 231 patients (231 tumors) treated with RFA alone.

Results

Median follow-up periods were similar in the TACE + RFA and RFA alone groups (37 vs. 38 months). During follow-up, local tumor progression was observed in 16% and 41% of tumors, respectively. The 1, 3, and 5 year local tumor progression-free survival rates were significantly higher in the TACE + RFA group (95%, 86%, and 83%, respectively) than in the RFA-alone group (78%, 61%, and 53%, respectively; P < 0.001). The 1, 3, and 5 year overall survival rates, however, were similar in the TACE + RFA (93%, 72%, and 63%, respectively) and RFA (93%, 73%, and 53%, respectively) groups (P = 0.545), as were the rates of major complications (1.2% vs. 0.4%).

Conclusions

Combined TACE and RFA was safe and provided better local tumor control than RFA alone in the treatment of 2- to 3-cm sized HCCs, although survival rates were similar.     

Single-session combined radiofrequency ablation and transarterial chemoembolization in the treatment of hepatocellular carcinoma

Aim of the study

To evaluate the efficacy of the combined use of both transarterial chemoembolization (TACE) and percutaneous radiofrequency ablation (RFA) in a single session for the treatment of large (≥3?cm in diameter) hepatocellular carcinoma.

Multivariate Analysis of the Predictors of Survival for Patients with Hepatocellular Carcinoma Undergoing Transarterial Chemoembolization: Focusing on Superselective Chemoembolization

Objective

While the prognostic factors of survival for patients with hepatocellular carcinoma (HCC) who underwent transarterial chemoembolization (TACE) are well known, the clinical significance of performing selective TACE for HCC patients has not been clearly documented. We tried to analyze the potential factors of disease-free survival for these patients, including the performance of selective TACE.

Materials and Methods

A total of 151 patients with HCC who underwent TACE were retrospectively analyzed for their disease-free survival (a median follow-up of 23 months, range: 1-88 months). Univariate and multivariate analyses were performed for 20 potential factors by using the Cox proportional hazard model, including 19 baseline factors and one procedure-related factor (conventional versus selective TACE). The parameters that proved to be significant on the univariate analysis were subsequently tested with the multivariate model.

Results

Conventional or selective TACE was performed for 40 and 111 patients, respectively. Univariate and multivariate analyses revealed that tumor multiplicity, venous tumor thrombosis and selective TACE were the only three independent significant prognostic factors of disease-free survival (p = 0.002, 0.015 and 0.019, respectively).

Conclusion

In our study, selective TACE was a favorable prognostic factor for the disease-free survival of patients with HCC who underwent TACE.     

Radiofrequency ablation combined with transcatheter arterial embolisation in rabbit liver: investigation of the ablation zone according to the time interval between the two therapies

Objectives

This study was designed to evaluate the extent of the radiofrequency ablation zone in relation to the time interval between transcatheter arterial embolisation (TAE) and radiofrequency ablation (RFA) and, ultimately, to determine the optimal strategy of combining these two therapies for hepatocellular carcinoma.

Methods

15 rabbits were evenly divided into three groups: Group A was treated with RFA alone; Group B was treated with TAE immediately followed by RFA; and Group C was treated with TAE followed by RFA 5 days later. All animals underwent perfusion CT (PCT) scans immediately after RFA. Serum liver transaminases were measured to evaluate acute liver damage. Animals were euthanised for pathological analysis of ablated tissues 10 days after RFA. Non-parametric analyses were conducted to compare PCT indices, the RFA zone and liver transaminase levels among the three experimental groups.

Results

Group B showed a significantly larger ablation zone than the other two groups. Arterial liver perfusion and hepatic perfusion index represented well the perfusion decrease after TAE on PCT. Although Group B showed the most elevated liver transaminase levels at 1 day post RFA, the enzymes decreased to levels that were not different from the other groups at 10 days post-RFA.

Conclusions

When combined TAE and RFA therapy is considered, TAE should be followed by RFA as quickly as possible, as it can be performed safely without serious hepatic deterioration, despite the short interval between the two procedures.Surgical resection is still considered standard curative therapy for hepatocellular carcinomas (HCCs), but only a small proportion of patients can undergo curative resection at initial presentation owing to the advanced stage of HCCs or liver dysfunction caused by an underlying liver disease [1,2]. Therefore, local ablation therapy, such as radiofrequency ablation (RFA), has been widely utilised as an alternative treatment. RFA shows promising results for managing HCCs less than 3 cm in diameter [3,4]. However, managing medium-sized and large HCCs with RFA seems to be less robust owing to the limited ablation zone. One of the main reasons is that intratumoral energy by RFA is insufficient to produce complete coagulation necrosis of liver tumours probably because of the heat dispersion by blood flow. To overcome these problems, transcatheter arterial embolisation (TAE) can reduce the heat sink effect for subsequent RFA when TAE is followed by RFA, which can lead to a larger ablation zone to treat larger HCCs [5-7]. Therefore, the combined therapy is beneficial compared with TAE or RFA alone due to a synergistic effect of those two therapies, particularly when treating larger HCCs (i.e. >3 cm diameter) that do not respond adequately to either procedure alone [6,8-13].No consensus exists on the time interval between combined TAE and RFA. Kang et al [13] reported on a single-session combined therapy in which RFA was performed immediately following chemoemobolisation. Takaki et al [12] reported on a dual-session combined therapy in which RFA was performed 1–2 weeks after TAE. The extent of the ablation zone and the safety of combined therapy in relation to the time interval between the two treatments have not been investigated. During the single-session combined therapy, the ablation zone is assumed to be larger than the dual-session combined therapy owing to the maximised perfusion reduction by TAE just prior to RFA. However, acute liver damage may be more severe with the single-session combined therapy than with the dual-session combined therapy.The aim of this study was to evaluate the differences in liver perfusion, the extent of the ablation zone and the degree of acute liver damage according to the time interval between TAE and RFA, and to determine the optimal strategy for combining these two therapies for treating HCCs.     

Early Stage Hepatocellular Carcinomas Not Feasible for Ultrasound-Guided Radiofrequency Ablation: Comparison of Transarterial Chemoembolization Alone and Combined Therapy with Transarterial Chemoembolization and Radiofrequency Ablation

Purpose

To report the results of combined therapy with transarterial chemoembolization (TACE) and radiofrequency ablation (RFA) for early stage hepatocellular carcinoma (HCC) considered infeasible for ultrasound (US)-guided RFA in comparison with those of TACE monotherapy.

Methods

From January 2007 through December 2010, 91 patients with early or very early stage HCC infeasible for US-guided RFA received either TACE alone (TACE group; n = 54) or TACE immediately followed by RFA (TACE–RFA group; n = 37) as a first-line treatment. 1-month tumor response, time to progression (TTP), and overall survival (OS) rates were calculated. Univariate and multivariate analyses were performed to identify prognostic factors.

Results

TACE–RFA group showed a better 1-month tumor response than TACE group (P < .001). The mean TTP was 29.7 ± 3.4 months (95 % confidence intervals [CIs] 23.0–36.5) in TACE group and 34.9 ± 2.8 months (95 % CIs 29.4–40.4) in TACE–RFA group. TACE–RFA group had a significantly longer TTP (P = .014). Cumulative 1-, 2-, and 3-year OS rates in the TACE and TACE–RFA groups were 91, 79, and 71 % and 100, 97, and 93 %, respectively (P = .008). Initial treatment of TACE was found to be the only significant risk factor for tumor progression and OS in multivariate analysis.

Conclusion

TACE–RFA combination therapy appears superior to TACE monotherapy in terms of 1-month tumor response, TTP, and OS when performed for early stage HCC infeasible for US-guided RFA.

     

Radiofrequency Ablation for Treating Liver Metastases from a Non-Colorectal Origin

Objective

We wanted to assess the safety and efficacy of performing radiofrequency ablation (RFA) in patients with non-colorectal liver metastases.

Materials and Methods

In this retrospective study, 25 patients with 40 hepatic metastases (M:F = 17:8; mean age, 57 years; tumor size, 0.5-5.0 cm) from a non-colorectal origin (stomach, biliary, breast, pancreas, kidney and skin) were treated with RFA. The RFA procedures were performed using either an internally cooled electrode or a clustered electrode under ultrasound or CT guidance. Contrast-enhanced CT scans were obtained immediately after RFA and follow-up CT scans were performed within three months after ablation and subsequently at least every six months. The intrahepatic disease-free interval was estimated and the overall survival from the time of the initial RFA was analyzed using the Kaplan-Meier method.

Results

No intraprocedural deaths occurred, but four major complications developed, including abscesses (n = 3) and pneumothorax (n = 1). Technical effectiveness was determined on the initial follow-up images. During the follow-up period (range, 5.9-68.6 months; median time, 18.8 months) for 37 tumors in 22 patients where technical effectiveness was achieved, 12 lesions (32%, 12 of 37) showed local tumor progression and new intrahepatic metastases occurred in 13 patients (59%, 13 of 22). The median intrahepatic disease-free interval was 10.1 months. The 1-year, 3-year and 5-year overall survival rates after RFA were 86%, 39% and 19%, respectively.

Conclusion

RFA showed intermediate therapeutic effectiveness for the treatment of non-colorectal origin liver metastases.     

Evaluation of the In Vivo Efficiency and Safety of Hepatic Radiofrequency Ablation Using a 15-G Octopus? in Pig Liver

Objective

To determine in vivo efficacy of radiofrequency ablation (RFA) in porcine liver by using 15-gauge Octopus® (15-G Octopus®) electrodes to create a large coagulation.

Materials and Methods

A total of 18 coagulations were created by using a 180-W generator and 15-G Octopus® electrodes during laparotomy, performed in 14 pigs. Coagulation necrosis was created in the pig livers by the use of one of three RFA protocols: 1) group A, monopolar RFA using a 15-G Octopus® electrode with a 5-mm inter-electrode distance (n = 4); 2) group B, monopolar RFA using a 15-G Octopus® electrode with a 10-mm inter-electrode distance (n = 6); and 3) group C, switching monopolar RFA using two 15-G Octopus® electrodes (n = 8). The energy efficiency, shape, maximum and minimum diameters (Dmx and Dmi), and the volume of the coagulation volume were measured in each group. The Summary statistics were obtained and Mann-Whitney test was were performed.

Results

The mean ablated volume of each group was 49.23 cm³ in A, 64.11 cm³ in B, and 72.35 cm³ in C. The mean Dmx and Dmi values were 5.68 cm and 4.58 cm in A and 5.97 cm and 4.97 cm in B, respectively. In group C, the mean diameters of Dmx and Dmi were 6.80 cm and 5.11 cm, respectively. The mean ratios of Dmi/Dmx were 1.25, 1.20, and 1.35 in groups A, B, and C, respectively. There was one animal death during the RFA procedure, the cause of which could not be subsequently determined. However, there were no other significant, procedure-related complications during the seven-hour-delayed CT scans.

Conclusion

RFA procedures using 15-G Octopus® electrodes are useful and safe for creating a large ablation in a single electrode model as well as in the multiple electrodes model.     

Polyvinyl Alcohol Embolization Adjuvant to Oily Chemoembolization in Advanced Hepatocellular Carcinoma with Arterioportal Shunts

Objective

To assess the feasibility and safety of polyvinyl alcohol (PVA) embolization adjuvant to transarterial oily chemoembolization (P-TACE) in advanced hepatocellular carcinoma (HCC) with arterioportal shunts (APS).

Materials and Methods

Nineteen patients who underwent PVA embolization for APS before a routine chemoembolization (TACE) procedure were retrospectively reviewed. 10 of these 19 patients underwent follow-up TACE or P-TACE after P-TACE (Group A), but nine patients underwent only initial P-TACE because of progression of HCC and/or underlying liver cirrhosis (Group B). Hepatic function tests, APS grades, and portal flow directions were evaluated before and after P-TACE sessions. Complications after procedures and survival days were also evaluated.

Results

In group A, APS grade was improved in eight patients and five of six patients with hepatofugal flow showed restored hepatopetal flow postoperatively. No immediate complication was developed in either group. Transient hepatic insufficiency developed in eight (42.1%) of 19 patients after P-TACE, and seven (87.5%) of these eight recovered within two weeks under conservative care. The mean and median survival time all study subjects was 280 days and 162 days.

Conclusion

P-TACE is feasible and safe in advanced HCC patients with APS.     

Saline-Enhanced Hepatic Radiofrequency Ablation Using a Perfused-Cooled Electrode: Comparison of Dual Probe Bipolar Mode with Monopolar and Single Probe Bipolar Modes

Objective

To determine whether saline-enhanced dual probe bipolar radiofrequency ablation (RFA) using perfused-cooled electrodes shows better in-vitro efficiency than monopolar or single probe bipolar RFA in creating larger coagulation necrosis.

Materials and Methods

RF was applied to excised bovine livers in both bipolar and monopolar modes using a 200W generator (CC-3; Radionics) and the perfused-cooled electrodes for 10 mins. After placing single or double perfused-cooled electrodes in the explanted liver, 30 ablation zones were created at three different regimens: group A; saline-enhanced monopolar RFA, group B; saline-enhanced single probe bipolar RFA, and group C; saline-enhanced dual probe bipolar RFA. During RFA, we measured the tissue temperature at 15mm from the electrode. The dimensions of the ablation zones and changes in the impedance currents and liver temperature during RFA were then compared between the groups.

Results

The mean current values were higher for monopolar mode (group A) than for the bipolar modes (groups B and C): 1550±25 mA in group A, 764±189 mA in group B and 819±98 mA in group C (p < 0.05). The volume of RF-induced coagulation necrosis was greater in group C than in the other groups: 27.6±2.9 cm³ in group A, 23.7±3.8 cm³ in group B, and 34.2±5.1 cm³ in group C (p < 0.05). However, there was no significant difference between the short-axis diameter of the coagulation necrosis in the three groups: 3.1±0.8 cm, 2.9±1.2 cm and 4.0±1.3 cm in groups A, B and C, respectively (p > 0.05). The temperature at 15 mm from the electrode was higher in group C than in the other groups: 70±18℃ in group A, 59±23℃ in group B and 96±16℃ in group C (p < 0.05).

Conclusion

Saline-enhanced bipolar RFA using dual perfused-cooled electrodes increases the dimension of the ablation zone more efficiently than monopolar RFA or single probe bipolar RFA.     

Intravascular Placement of Metallic Coils as Lung Tumor Markers for CyberKnife Stereotactic Radiation Therapy

Objective

To present our experience with placing endovascular coils in pulmonary arteries used as a fiducial marker for CyberKnife therapy and to describe the technical details and complications of the procedure.

Materials and Methods

Between June 2005 and September 2013, 163 patients with primary or secondary lung malignancies, referred for fiducial placement for stereotactic radiosurgery, were retrospectively reviewed. Fourteen patients (9 men, 5 women; mean age, 70 years) with a history of pneumonectomy (n = 3), lobectomy (n = 3) or with severe cardiopulmonary co-morbidity (n = 8) underwent coil (fiducial marker) placement. Pushable or detachable platinum micro coils (n = 49) 2-3 mm in size were inserted through coaxial microcatheters into a small distal pulmonary artery in the vicinity of the tumor under biplane angiography/fluoroscopy guidance.

Results

Forty nine coils with a median number of 3 coils per tumor were placed with a mean tumor-coil distance of 2.7 cm. Forty three (87.7%) of 49 coils were successfully used as fiducial markers. Two coils could not be used due to a larger tumor-coil distance (> 50 mm). Four coils were in an acceptable position but their non-coiling shape precluded tumor tracking for CyberKnife treatment. No major complications needing further medication other than nominal therapy, hospitalization more than one night or permanent adverse sequale were observed.

Conclusion

Endovascular placement of coil as a fiducial marker is safe and feasible during CyberKnife therapy, and might be an option for the patients in which percutaneous transthoracic fiducial placement might be risky.     

Combined versus single locoregional therapy in the treatment of unresectable hepatocellular carcinoma

Introduction

Surgical and locoregional therapies are different options in HCC treatment, several locoregional techniques are used.

Purpose

This study aimed to assess the effectiveness of transarterial chemoembolization (TACE), radiofrequency ablation (RFA) and combined therapy, in HCC management.

Materials and methods

The study was conducted at our University Hospital, from August 2011 to February 2013. It included 60 patients with HCC (40 males and 20 females, age ranged between 45 and 70 years). Patients were classified into 3 groups, group 1 treated with TACE, group 2 with RFA, and group 3 with both techniques. Response was assessed by triphasic CT and alpha fetoprotein. Patients were classified into good and poor responders after one and six months and one year. Patients’ survival and incidence of recurrence were recorded.

Results

The percentage of good responders was greater with combined therapy than with TACE and RFA (90%, 70%, and 60% respectively). The overall survival was 75% and the recurrence free survival was 60% in TACE, 90%, and 45% in RFA and 95% and 90% in combined therapy respectively.

Conclusion

Combined therapy is superior regarding good response, overall survival, and free recurrence survival than either TACE or RFA alone.     

Saline-Enhanced Radiofrequency Thermal Ablation of the Lung: A Feasibility Study in Rabbits

Objective

To assess the feasibility and safety of CT-guided percutaneous transthoracic radiofrequency ablation (RFA) with saline infusion of pulmonary tissue in rabbits.

Materials and Methods

Twenty-eight New Zealand White rabbits were divided into two groups: an RFA group (n=10) and a saline-enhanced RFA (SRFA) group (n=18). In the RFA group, percutaneous RFA of the lung was performed under CT guidance and using a 17-gauge internally cooled electrode. In the SRFA group, 1.5 ml of 0.9% saline was infused slowly through a 21-gauge, polyteflon-coated Chiba needle prior to and during RFA. Lesion size and the healing process were studied in rabbits sacrificed at times from the day following treatment to three weeks after, and any complications were noted.

Results

In the SRFA group, the mean diameter (12.5 ± 1.6 mm) of acute RF lesions was greater than that of RFA lesions (8.5 ± 1.4 mm) (p < .05). The complications arising in 12 cases were pneumothorax (n=8), thermal injury to the chest wall (n=2), hemothorax (n=1), and lung abscess (n=1). Although procedure-related complications tended to occur more frequently in the SRFA group (55.6%) than in the RFA group (20%), the difference was not statistically significant (p = .11).

Conclusion

Saline-enhanced RFA of pulmonary tissue in rabbits produces more extensive coagulation necrosis than conventional RFA procedures, without adding substantial risk of serious complications.     

Computed Tomographic-Guided Radiofrequency Ablation of Recurrent or Residual Hepatocellular Carcinomas around Retained Iodized Oil after Transarterial Chemoembolization

Objective

To assess the clinical efficacy, safety, and risk factors influencing local tumor progression, following CT-guided radiofrequency ablation (RFA) of recurrent or residual hepatocellular carcinoma (HCC), around iodized oil retention.

Materials and Methods

Sixty-four patients (M : F = 51 : 13, 65.0 ± 8.2 years old) with recurrent or residual HCC (75 index tumors, size = 14.0 ± 4.6 mm) had been treated by CT-guided RFA, using retained iodized oil as markers for targeting. The technical success, technique effectiveness rate and complications of RFA were then assessed. On pre-ablative and immediate follow-up CT after RFA, we evaluated the size of enhancing index tumors and iodized oil retention, presence of abutting vessels, completeness of ablation of iodized oil retention, and the presence of ablative margins greater than 5 mm. Also, the time interval between transarterial chemoembolization and RFA was assessed. The cumulative local tumor progression rate was calculated using the Kaplan-Meier method, and the Cox proportional hazards model was adopted, to clarify the independent factors affecting local tumor progression.

Results

The technical success and technique effectiveness rate was 100% and 98.7%, respectively. Major complications were observed in 5.6%. The cumulative rates of local tumor progression at 1 and 2 years were 17.5% and 37.5%, respectively. In multivariate analyses, partial ablation of the targeted iodized oil retention was the sole independent predictor of a higher local tumor progression rate.

Conclusion

CT-guided RFA of HCC around iodized oil retention was effective and safe. Local tumor progression can be minimized by complete ablation of not only index tumors, but targeted iodized oil deposits as well.