Histological, CT, and intraoperative ultrasound appearance of hepatic tumors previously treated by laparoscopic radiofrequency ablation

Chronological changes of radiofrequency ablation zone in rabbit liver: an in vivo correlation between gross pathology and histopathology

OBJECTIVE

To examine the gross pathology and histopathology of ablation zones created from radiofrequency (RF) ablation and to correlate their chronological changes.

METHODS

A total of 48 in vivo ablation zones (16 rabbit livers) were obtained immediately after and also 30 min, 1 h and 2 h after RF ablation and were subjected to haematoxylin and eosin (H&E) staining, nicotinamide adenine dinucleotide (NADH) diaphorase staining, terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) staining. Chronological changes in gross pathology and histopathology were evaluated and correlated with each other.

RESULTS

Peripheral red zones on gross pathology correlated with peripheral zones on H&E staining, lightly stained peripheral zones on NADH staining and peripheral positive zones on TUNEL staining. Central white zones on gross pathology correlated with combined central and border zones on H&E staining, central negative zones on NADH staining and combined central-positive and middle-negative zones on TUNEL staining. Boundary visibility between central white and peripheral red zones on gross pathology was significantly higher at 1 and 2 h than immediately after RF ablation. As time increased after RF ablation, visibility of the border zone on H&E staining and the grade of positively stained hepatocytes in the peripheral zone on TUNEL staining increased.

CONCLUSION

Chronological changes in gross pathology of RF ablation zones correlated well with histopathology. The boundary between the central white and peripheral red zones tended to become clear at 1 h after RF ablation. Advances in knowledge: (1) RF ablation zones show chronological changes on gross pathology and histopathology. (2) Gross pathology and histopathology correlate well with each other.

Laparoscopy-Guided Transthoracic Transdiaphragmatic Radiofrequency Ablation for Hepatic Tumors Located Beneath the Diaphragm

BACKGROUND

It is often difficult to perform percutaneous radiofrequency ablation (RFA) for hepatic tumors beneath the diaphragm. Diaphragmatic thermal damage is one of the fatal late complications of percutaneous transdiaphragmatic RFA. Our experience with laparoscopic transthoracic transdiaphragmatic intraoperative RFA (LTTI-RFA) for hepatic tumors beneath the diaphragm is reported.

METHODS

Ten patients who underwent LTTI-RFA from 2009 to 2012 were evaluated. Two cases had concomitant partial hepatectomy, and one underwent RFA for two tumors at the same time. The diagnosis was hepatocellular carcinoma in eight cases and metastatic hepatic tumors in two cases. Nine of eleven tumors were located at segments 7 and 8. Nine tumors were less than 20 mm in diameter. The patients were placed in the half left lateral decubitus position with single-lumen tube intubation. After placement of four abdominal ports, a 12-mm port was inserted in the fourth or fifth intercostal space into the diaphragm. The tumor was ablated by an RFA needle through the port. The routine follow-up consisted of laboratory tests and abdominal imaging every 3-6 months.

RESULTS

The median operation time for only one tumor was 137 minutes (range, 105-187 minutes). The median number of times for ablation was three. Severe postoperative complications (>Clavien-Dindo IIIa) were observed in one case (right upper limb paralysis). The median follow-up period was 35 months (range, 11-43 months). There was no local tumor progression. Recurrent hepatic tumor appearance occurred in other parts of the liver in 6 of the 11 patients.

CONCLUSIONS

Laparoscopic transthoracic transdiaphragmatic RFA is an acceptable procedure with a low rate of local recurrence.

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.

Treatment of malignant liver tumors by radiofrequency ablation combined with low-frequency ultrasound radiation with microbubbles

Objective

To explore the therapeutic efficacy and safety of malignant liver tumor treatment by radiofrequency ablation (RA) combined with low frequency ultrasound radiation with microbubbles (LFURM).

Methods

Retrospective analysis of 25 patients with malignant hepatic tumors treated by RA/LFURM in the Department of Hepatobiliary Surgery of Kunming General Hospital affiliated to Chengdu Military District, PLA from January 2010 to June 2011. Ultrasound guided RA was performed, which was followed one week later by LFURM. Basal contrast ultrasound, liver function tests, and serum alpha fetoprotein (AFP) were obtained, and repeated 3 and 6 months after treatment. T-test and chi-square were used to compare parametric and non-parametric variables respectively.

Results

In 17 cases, gross tumor volume was significantly reduced 6 months after treatment while mean tumor showed a reduction of 50% compared to pre-treatment values. In 7 cases gross tumor volumes reduction was partial, but surrounding tumor tissue showed blood flow signals. One patient had no reduction in gross tumor volume. Levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), alpha fetoprotein (AFP) decreased significantly 6 months after treatment (all p<0.05). No tumor recurrence was seen during the 6 month follow-up. Quality of life scores (QOL) were good in 21 patients (84%), improved in 2 patients (8%), unchanged in 1 patient (4%) and got worst in 1 patient (4%). Karnofsky scores (KPS) improved in 19 patients (76%), remained unchanged in 5 patients (2%) and got worst in 1 patient (4%). Both QOL and KPS changes were statistically significant (P<0.05).

Conclusion

RA/LFURM treatment of liver tumors is efficient and safe, and can reduce the gross tumor volumes and protect liver function.

Recent progress in the understanding, diagnosis, and treatment of gastroenteropancreatic neuroendocrine tumors

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are relatively rare tumors that arise from the diffuse neuroendocrine system. This heterogeneous group of tumors was often considered a single entity. This belied their biological diversity, and the biggest advance in understanding these tumors over the past decades has been in understanding this diversity. Diagnosis of these tumors has been aided by advances in pathological diagnosis and classification and tumor imaging with endoscopic ultrasound and somatostatin receptor fusion imaging. Genetic and molecular advances have identified molecular targets in the treatment of these tumors. Surgery remains the mainstay of treatment, amply supported by interventional radiological techniques, including embolization. Treatment of metastatic disease has improved significantly with the addition of several new agents, including tyrosine kinase inhibitors, mammalian target of rapamycin inhibitors, and yttrium-90-DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) and lutetium-177-DOTA octreotate. Despite significant advances in the understanding and management of GEP-NETs, the survival of patients remains largely unchanged and there remains a need for the development of national and international research collaborations to spearhead future efforts.

Ultrasound-based elastography: a novel approach to assess radio frequency ablation of liver masses performed with expandable ablation probes: a feasibility study

OBJECTIVE

The purpose of this study was to evaluate the technical feasibility of ultrasound-based elastography as a tool for assessing the size and shape of the coagulation necrosis caused by radio frequency ablation (RFA) probes using expandable electrodes ex vivo as well as in a patient with a liver metastasis.

METHODS

A commercially available expandable RFA probe was used to create a 3-cm ablation in a piece of bovine liver. The ablation probe was used in situ to induce tissue deformation for elastography before and after ablation. Ultrasonic radio frequency data were processed to generate elasticity strain images. The appearance of the ablation zone was compared with magnetic resonance imaging and a gross section specimen. One patient with malignant metastatic disease to the liver and a clinical indication for RFA was investigated for the feasibility of percutaneous elastography of RFA using the same technique. Sonographic strain images were compared with the appearance of the nonenhancing ablation zone on contrast-enhanced computed tomography.

RESULTS

Ex vivo, the ablation zone on ultrasound-based elastography was represented by an area of increased stiffness and was well demarcated from the nonablated surrounding tissue. The size and shape of the ablated zone on the strain image correlated well with the gross specimen and the magnetic resonance imaging appearance. Strain images obtained from the patient showed results similar to those of the ex vivo experiment and correlated well with the nonenhancing area of ablation on contrast-enhanced computed tomography.

CONCLUSIONS

Ultrasound-based elastography may be a promising tool for displaying the ablation zone created by expandable RFA probes.