Ultrasound-guided percutaneous microwave coagulation therapy with a "cooled-tip needle" for the treatment of hepatocellular carcinoma adjacent to the gallbladder

Efficacy and safety of percutaneous microwave ablation for hepatocellular carcinomas <4 cm in difficult location

OBJECTIVE

Tumor location is a critical factor for determining technical success and local recurrence following percutaneous ablation of hepatocellular carcinomas (HCC). The purpose of this retrospective study was to evaluate the safety and outcome measures of percutaneous microwave ablation (pMWA) for HCCs <4 cm in difficult locations.

METHODS

Retrospective review included 81 patients who underwent pMWA for HCCs <4 cm. Fourty-three patients (30 males and 13 females; mean age, 61 years) with 53 HCCs located near the diaphragm, heart, gallbladder, kidney, gastrointestinal tract, large vessel and exophytic location were included under difficult location group. Thirty-eight patients (29 males and nine females; mean age, 60 years) with 48 HCCs in other locations were included under control group. Baseline demographics were recorded. Technical efficacy, local tumor progression (LTP), and complication rates were evaluated.

RESULTS

Mean follow-up period was 3.4 months (range 1-7). There was no major complication in both the groups; two patients had a mild perihepatic hemorrhage in the difficult location group which was managed conservatively. There was no difference between the groups in the overall technical efficacy rate (84.9% vs 91.7%, p = 0.294), LTP rate (4.4% vs 2.2%. p = 0.57) or complication rate (4.6% vs 0%, p = 0.177).

CONCLUSION

Our data suggest that there is no significant difference in technical efficacy, LTP or complication rates for MWA in both difficult and normal locations.

ADVANCES IN KNOWLEDGE

With proper patient selection, pre-procedural planning and appropriate technique, pMWA is feasible, safe, and effective for small HCCs in difficult location with an acceptable range of complications.

Hydrodissection of the Gallbladder Bed: A Technique for Ablations Located Close to the Gallbladder

OBJECTIVE

To report the technique of hydrodissection of the gallbladder bed, in order to separate the gallbladder wall from the liver surface during microwave ablation of liver malignancies located in segment V.

MATERIALS AND METHODS

Between January 2018 and March 2018, percutaneous hydrodissection of the gallbladder fossa was performed during four microwave ablation procedures in three patients (One patient was treated twice for the same lesion, making a total of four procedures for three lesions.) All treated lesions were located in segment V and abutting the gallbladder. Number of hydrodissection needles, volume of hydrodissection, repartition of hydrodissection, separation of tumour from the gallbladder post-hydrodissection, technical success of hydrodissection/ablation, and complications were recorded and evaluated.

RESULTS

Hydrodissection of the gallbladder fossa was technically feasible in all four procedures, and microwave ablation was performed at maximum power without any early interruption. Time to perform hydrodissection was 11.3 min on average (range 7-18 min). Minimal distance between the ablation area and the GB increased from virtual to 10 mm on average (range 6-13), with a mean volume of dissection of 65 ml (range 40-100). Technical success was 75%. There was no complication related to the hydrodissection itself, and no acute or delayed gallbladder complication.

CONCLUSION

Hydrodissection of the gallbladder bed is a feasible technique to separate the gallbladder from the liver surface. This could potentially decrease the risk of thermal injuries to the gallbladder wall when ablating tumours located in segment V.

Radiofrequency ablation of liver cancers adjacent to the gallbladder without gallbladder isolation under contrast-enhanced ultrasound monitoring: a preliminary study

PURPOSE

The purpose of this study was to investigate the feasibility, safety and efficacy of intra-procedural contrast-enhanced ultrasound (CEUS) monitoring of the radiofrequency ablation (RFA) of liver cancers adjacent to gallbladder (GB) without GB isolation.

MATERIALS AND METHODS

From May 2016 to July 2017, patients with liver cancers adjacent to GB (≤10 mm) who intended to undergo ultrasound-guided RFA without GB isolation in our hospital were prospectively enrolled. During the RFA procedures, CEUS was employed to evaluate the therapeutic response and the perfusion of the intact GB wall. The outcomes of GB and liver cancers were followed up and recorded.

RESULTS

23 patients (18 male, 5 female) with 23 liver cancers (mean 18 mm, range 8-34 mm) adjacent to GB were enrolled. There were 12 tumors that abutted the GB while 11 tumors located within 10 mm of the GB. After the RFA procedures, intra-procedural CEUS evaluation demonstrated the perfusion of the GB wall was intact in all 23 patients and technical success rate of RFA was 100% (23/23). According to the contrast-enhanced CT/MR one month after RFA, the technical efficacy rate was 100% (23/23). During the follow-up period (range: 12-23 months, median: 17 months), no local tumor progression occurred and no major complications arised. Overall survival at 1-year was 100%. Thickening of GB wall was detected in 11 patients. The thickness of GB wall returned to the pre-ablation level in five patients.

CONCLUSION

CEUS-monitored RFA of liver cancers adjacent to GB without GB isolation was feasible, safe and effective.

The effect of lipiodol deposition in HCC after TACE on the necrosis range of PMCT

Objective

To study the impact of lipiodol deposition in the lesion of hepatocellular carcinoma (HCC) after transarterial chemoembolization (TACE) on the necrosis area of percutaneous microwave coagulation therapy (PMCT).

Materials and methods

A total of 44 patients with HCC with 56 nodules, with a size ranging from 1.5 to 3.5 cm, was selected in our study. About 23 patients (26 nodules) underwent PMCT treatment only as Group A and 21 patients (30 nodules) were treated by PMCT-combined TACE as Group B. All patients underwent PMCT with single-electrode and one-point ablation. Paired t-test was used to analyze pre- and postoperatively the volume of tumor and the necrosis volume after PMCT. Independent t-test was used to compare the difference in the necrosis area between two groups (α=0.05).

Results

All patients underwent PMCT or PMCT combined with TACE successfully. The tumor and necrosis size of Group A was 16.29±19.23 cm³ and 17.98±18.49 cm³ (P=0.650), and 11.95±12.78 cm³ and 16.60±11.70 cm³ of Group B (P=0.017). There was no significant difference on necrosis volume between the two groups (P=0.581). The necrosis area of Group B was larger than the size of the tumor (P=0.017), but the ablation area of the two groups was smaller than the theoretic area (P=0.001). (The theoretic area means that the necrosis area of ablation should be 1.0 cm larger than the tumor in diameter.)

Conclusion

PMCT combined with TACE could enlarge the ablation area, but will not lead to an ideal necrosis area than the PMCT alone. The lipiodol deposition in the tumor lesion may hinder the expansion of the heating field. Therefore, further research was needed.

Practice guidelines for ultrasound-guided percutaneous microwave ablation for hepatic malignancy

Primary liver cancer and liver metastases are among the most frequent malignancies worldwide, with an increasing number of new cases and deaths every year. Traditional surgery is only suitable for a limited proportion of patients and imaging-guided percutaneous thermal ablation has achieved optimistic results for management of hepatic malignancy. This synopsis outlines the first clinical practice guidelines for ultrasound-guided percutaneous microwave ablation therapy for hepatic malignancy, which was created by a joint task force of the Society of Chinese Interventional Ultrasound. The guidelines aim at standardizing the microwave ablation procedure and therapeutic efficacy assessment, as well as proposing the criteria for the treatment candidates.