Imaging findings after liver resection by using radiofrequency parenchymal coagulation devices: initial experiences

The impact of additional margin coagulation with radiofrequency in liver resections with subcentimetric margin: can we improve the oncological results? A propensity score matching study

BACKGROUND

Whereas the usefulness of radiofrequency (RF) energy as haemostatic method in liver surgery has become well established in the last decades, its intentional application on resection margins with the aim of reducing local recurrence is still debatable. Our goal was to compare the impact of an additional application of RF energy on the top of the resection surface, namely additional margin coagulation (AMC), on local recurrence (LR) when subjected to a subcentimeter margin.

METHODS

We retrospectively analyzed 185 patients out of a whole cohort of 283 patients who underwent radical hepatic resection with subcentimetric margin. After propensity score adjustment, patients were classified into two balanced groups according to whether RF was applied or not.

RESULTS

No significant differences were observed within groups in baseline characteristics after PSM adjustment. The LR rate was significantly higher in the Control than AMC Group: 12 patients (14.5%) vs. 4 patients (4.8%) (p = 0.039). The estimated 1, 3, and 5-year LR-free survival rates of patients in the Control and AMC Group were: 93.5%, 86.0%, 81.0% and 98.8%, 97.2%, 91.9%, respectively (p = 0.049). Univariate Cox analyses indicated that the use of the RF applicator was significantly associated with lower LR (HR = 0.29, 95% confidence interval 0.093-0.906, p = 0.033). The Control Group showed smaller coagulation widths than the AMC group (p < 0.001).

CONCLUSIONS

An additional application of RF on the top of the resection surface is associated with less local hepatic recurrence than the use of conventional techniques.

PET/CT Variants and Pitfalls in Liver, Biliary Tract, Gallbladder and Pancreas

A wide variety of pathological anomalies may occur in the liver, biliary system, and pancreas. It is a necessity to use many different imaging techniques in order to distinguish such varied pathologies, especially those from malignant processes. Positron Emission Tomography/Computed Tomography (PET/CT) is an imaging method that has proven its diagnostic value in oncology and can be used for different clinical purposes. Fluoro-18 fluoro-2-deoxy-D-glucose has a wide range of uses as a dominant radiopharmaceutical in routine molecular imaging, however, molecular imaging has started to play a more important role in personalized cancer treatment in recent years with new Fluoro-18 and Gallium-68 labeled tracers. Although molecular imaging has a strong diagnostic effect, the surprises and pitfalls of molecular imaging can lead us to unexpected and misleading results. Prior to PET/CT analysis and reporting, information about possible technical and physiological pitfalls, normal histological features of tissues, inflammatory pathologies, specific clinical features of the case, treatment-related complications and past treatments should be evaluated in advance to avoid misinterpretation. In this review, the physiological and pathophysiological variants as well as pitfalls encountered in PET/CT imaging of the liver, biliary tract, gallbladder, and pancreas will be examined. Other benign and malignant pathologies that have been reported to date and that have led to incorrect evaluation will be listed. It is expected that the devices, software, and artificial intelligence applications that will be developed in the near future will enable much more effective and faster imaging that will reduce the potential causes of error. However, as a result of the dynamic and evolving structure of the information obtained by molecular imaging, the inclusion of the newly developed radiopharmaceuticals in routine practice will continue to carry new potentials as well as new troubles. Although molecular imaging will be the flagship of diagnostic oncology in the 21st century, the correct analysis and interpretation by the physician will continue to form the basis of achieving optimal performance.

Flu-like symptoms following radiofrequency liver transection: a new variety of the post-radiofrequency syndrome

BACKGROUND/AIMS

The aim of our study was to determine whether post-radiofrequency syndrome may also develop following hepatectomy using saline-cooled radiofrequency coagulation.

METHODS

We retrospectively reviewed 95 consecutive patients who underwent 110 liver resections between May 2000 and September 2012. We stated that 80.9% of the resections were carried out employing the saline-cooled radiofrequency device. All medical records were searched for the occurrence of flu-like symptoms, without evidence of sepsis or infection, in the first two postoperative weeks.

RESULTS

Eleven patients (11.5%) developed flu-like symptoms after hepatectomy without evidence of sepsis or infection. All their hepatectomies were performed employing the saline-cooled radiofrequency probe (p = .089), and all cases but one appeared following colorectal liver metastases surgery (p = .042). Eight of them were readmitted to the hospital because of their symptoms. In all 11 cases, a fluid collection was present, 8 of them with gas presence. Nine patients underwent a percutaneous drainage whose cultures were negative. Ten patients recovered without treatment or with the intake of nonsteroidal anti-inflammatory drugs within 1 week, but one patient developed a secondary infection with gram-positive bacteria after percutaneous drainages that prolonged his hospital stay.

CONCLUSION

Liver splitting using saline-cooled radiofrequency coagulation may cause postoperative symptoms that may mimic surgical site infection. Surgeons employing this device should keep this in mind to avoid potentially unwarranted treatments that may be unnecessary, expensive, and even harmful.

Imaging appearance of treated hepatocellular carcinoma

Surgical resection and imaging guided treatments play a crucial role in the management of hepatocellular carcinoma (HCC). Although the primary end point of treatment of HCC is survival, radiological response could be a surrogate end point of survival, and has a key role in HCC decision-making process. However, radiological assessment of HCC treatment efficacy is often controversial. There are few doubts on the evaluation of surgical resection; in fact, all known tumor sites should be removed. However, an unenhancing partial linear peripheral halo, in most cases, surrounding a fluid collection reducing in size during follow-up is demonstrated in successfully resected tumor with bipolar radiofrequency electrosurgical device. Efficacy assessment of locoregional therapies is more controversial and differs between percutaneous ablation (e.g., radiofrequency ablation and percutaneous ethanol injection) and transarterial treatments (e.g., conventional transarterial chemoembolization, transarterial chemoembolization with drug eluting beads and radioembolization). Finally, a different approach should be used for new systemic agent that, though not reducing tumor mass, could have a benefit on survival by delaying tumor progression and death. The purpose of this brief article is to review HCC imaging appearance after treatment.

Value of percutaneous radiofrequency ablation with or without percutaneous vertebroplasty for pain relief and functional recovery in painful bone metastases

OBJECTIVE

To evaluate the effectiveness of percutaneous radiofrequency (RF) ablation with or without percutaneous vertebroplasty (PV) on pain relief, functional recovery and local recurrence at 6 months' follow-up (FU), in patients with painful osseous metastases.

MATERIALS AND METHODS

Thirty RF ablations were performed in 24 patients (mean age: 61 years) with bone metastases. Half of the patients had an additional PV. The primary end point was pain relief evaluated by a visual analogue scale (VAS) before treatment, and at 1 and 6 months' FU. Functional outcome was assessed according to the evolution of their ability to walk at 6 months' FU. Imaging FU was available in 20 out of 24 patients with a mean delay of 4.7 months.

RESULTS

Reduction of pain was obtained at 6 months FU in 81% of cases (15 out of 18). Mean pretreatment VAS was 6.4 (±2.7). Mean VAS was 1.9 (±2.4) at 1 month FU, and 2.3 (±2.9) at 6 months' FU. Pain was significantly reduced at 6 months FU (mean VAS reduction = 4.1; P < 0.00001). Functional improvement was obtained in 74% of the cases. Major complications rate was 12.5 % (3 out of 24) with 2 skin burns, and 1 case of myelopathy. Local tumour recurrence or progression was recorded in 5 cases.

CONCLUSION

Radiofrequency ablation is an effective technique in terms of pain relief and functional recovery for the treatment of bone metastases, which provides a relatively low rate of local recurrence.

Imaging findings of liver resection using a bipolar radiofrequency electrosurgical device--initial observations

OBJECTIVE

To assess contrast-enhanced US (CEUS), computed tomography (CT) and magnetic resonance (MR) imaging findings and serial changes of the treated area at follow-up in patients who underwent liver resection using a bipolar radiofrequency electrosurgical device.

METHODS

Imaging findings of 27 patients with resected hepatocellular carcinomas (HCCs) (n=24) and metastases (n=3) (mean size: 2.6cm), were retrospectively evaluated. Two readers assessed: the (a) presence, (b) thickness, (c) shape and (d) echogenicity (CEUS)/attenuation (CT)/signal intensity (MR imaging) at coagulated site and the (e) presence of residual tumor of the bipolar radiofrequency electrosurgical device resection margin.

RESULTS

Follow-up was performed with either CT (n=20) or MR imaging (n=7) and repeated in 16 patients with CT (n=7), MR imaging (n=4), or both techniques (n=5). Four patients also had a single CEUS examination. At first imaging follow-up a peripheral halo was depicted at resection site (100%). A fluid collection within the surgical area was found in 67% of patients. During the following imaging examinations a progressive involution of both findings was observed, respectively, in 81% and 62% of patients. Viable tissue was detected in three patients (11%).

CONCLUSIONS

After liver resection with bipolar radiofrequency electrosurgical device successfully ablated tumor is demonstrated at imaging by an unenhancing partial linear peripheral halo, in most cases, surrounding a fluid collection reducing in size during follow-up.

Combined blunt-clamp dissection and LigaSure ligation for hepatic parenchyma dissection: postcoagulation technique

BACKGROUND

Blunt-clamp dissection allows for visualization of intrahepatic vessels and individual ligation of major blood or bile vessels. Recently, many instruments have been developed for "precoagulation" of liver parenchyma before sharp transection, but suffer from the possibility of injuring major blood and biliary vessels that are not well-visualized, along with high cost. In this article, we describe a "postcoagulation" technique combining clamp dissection and sealing of vessels under direct vision using a tissue-sealing device.

STUDY DESIGN

Clinical evaluation of 400 patients from 2 centers subjected to liver resection using this technique.

RESULTS

There were no cases complicated by hemorrhage. There was an incidence of 1.8% for bile leaks. This low incidence of biloma formation was seen even with the high incidence (49%) of abnormal parenchyma encountered in this cohort.

CONCLUSIONS

Combining the clamp-crushing method with use of the LigaSure device (Valleylab) allows identification of intraparenchymal vessels followed by sealing. This method of parenchymal transaction optimizes ease of use with confidence in vessel ligation.

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.

Primary Cancer of the Liver and Biliary Duct

F-18-FDG PET and PET/CT are useful for staging, predicting the prognosis, and evaluating recurrence and treatment response in hepatocellular carcinomas (HCCs) and cholangiocarcinomas. Increased F-18-FDG uptake within tumors could be a surrogate marker of aggressive behavior and poor clinical outcome, despite high false-negative rates in detecting primary intrahepatic low-grade HCCs and periductal-infiltrating cholangiocarcinomas. Dualtracer PET or PET/CT using carbon-11-acetate and F-18-FDG will increase diagnostic performance in HCC.