Software-based assessment of tumor margins after percutaneous thermal ablation of liver tumors: A systematic review.

PURPOSE: The purpose of this study was to make a systematic review of clinical studies evaluating software-based tumor margin assessment after percutaneous thermoablation (PTA) of liver tumors. MATERIALS AND METHODS: A systematic literature search was performed through Pubmed/MEDLINE, Embase and the Cochrane Library. Original studies published in English that reported on software-based assessment of ablation margins (AM) following PTA of liver tumors were selected. Studies were analyzed with respect to design, number of patients and tumors, tumor type, PTA technique, tumor size, target registration error, study outcome(s) (subtypes: feasibility, comparative, clinical impact, predictive or survival), and follow-up period. RESULTS: Twenty-nine articles (one multi-center and two prospective studies) were included. The majority were feasibility (26/29, 89.7%) or predictive (23/29, 79.3%) studies. AM was a risk factor of local tumor progression (LTP) in 25 studies (25/29, 86.2%). In nine studies (9/29, 31%) visual assessment overestimated AM compared with software-aided assessment. LTP occurred at the location of the thinnest margin in nine studies (9/29, 31%). Time for registration and analysis was heterogeneously reported, ranging between 5-30 min. Mean target registration error was reported in seven studies (7/29, 24.1%) at 1.62 mm (range: 1.20-2.23 mm). Inter-operator reproducibility was high (kappa range: 0.686-1). Ascites, liver deformation and inconspicuous tumor were major factors of co-registration error. CONCLUSION: Available studies present a low level of evidence overall, since most of them are feasibility, retrospective and single-center studies.

Learning curve of liver stiffness measurement using a new hybrid machine composed of transient elastography interfaced with ultrasound.

OBJECTIVES: To assess the learning curve for performing reliable liver stiffness measurements using a new hybrid machine composed of transient elastography (TE) interfaced with an ultrasound device for radiographers and radiologists with different levels of expertise in ultrasound imaging. METHODS: Ten novice operators who had never performed TE measurements were prospectively evaluated from April to October 2018: senior radiologists, young radiologists, fellows, radiographers, and residents, with different levels of experience in abdominal ultrasound imaging. All operators had a short theoretical training followed by a training session under supervision in three patients. Then, each operator had to perform TE in 50 consecutive patients with chronic liver disease, using beforehand ultrasound examination to select measurement area in the right liver lobe, and if needed, the XL probe. Percentages of failures and reliable measurements were compared. RESULTS: The rates of failures of measurements, poorly reliable, reliable, and very reliable results, were of 4.2% (21/500), 2.4% (12/500), 47.6% (238/500), and 45.8% (229/500), respectively. The rates of reliable plus very reliable results were excellent, ranging from 91 to 96% among all the subgroups. The rates of very reliable, reliable, and unreliable results did not differ between operator subgroups and especially between junior radiologists, senior radiologists, and radiographers. No breaking point was observed in the interquartile range/median values over time. CONCLUSION: TE interfaced with ultrasound in this hybrid machine presents no learning curve effect. After a short initial training session, a novice observer is able to perform high rates of reliable and very reliable TE measurements. KEY POINTS: • When performing liver stiffness measurements using a new hybrid machine composed of transient elastography interfaced with ultrasound, the rate of failures of measurements is very low, below 5%. • After a short training session and using ultrasound planning, a novice operator, whatever its expertise in ultrasound imaging, is capable of performing high rates of reliable and very reliable measurements. • No learning curve is needed for performing reliable liver stiffness measurements using this new hybrid machine.

Transarterial Chemoembolization of Hepatocellular Carcinoma with Idarubicin-Loaded Tandem Drug-Eluting Embolics.

: Objective: To describe the responses, toxicities and outcomes of HCC patients treated by transarterial chemoembolization (TACE) using idarubicin-loaded TANDEM beads. Materials and Methods: Seventy-two consecutive patients (mean age: 71 years (58-84 years)) with HCC were treated by TACE using idarubicin-loaded TANDEM in a first line, over a five-year period. Most patients (89%) had liver cirrhosis classified as Child-Pugh A (90%). BCLC B classification applied in 85% of cases. Baseline tumor burden was limited to one to three nodules in 92% of cases, unilobar in 88% cases, with a median tumor diameter of 55 mm (range: 13-150 mm). Toxicity was assessed using NCI CTC AE v4.0. Response was assessed using mRECIST criteria. Time-to-treatment failure (TTTF) and overall survival (OS) were also calculated based on Kaplan-Meier method. Result: Of 141 TACE sessions performed with bead sizes of 100 and 75 µm in 42 (29.8%) and 99 (70.2%) sessions, respectively. In 78% of all TACE sessions, the full dose of idarubicin-loaded beads was injected. Grade 3-4 AE were observed after 73 (52%) sessions, most of them being biological. Multi-organ failure was observed three days after the first TACE in a Child B patients, unfortunately leading to death. Overall, the best objective response rate (ORR) was 65%. Median follow-up lasted 14.3 months (95% CI: 11.2-18.8 months). Median TTTF and OS were 14.4 months (95% CI: 7.2-24.6 months) and 34.6 months (95% CI: 24.7-not reached) respectively. Conclusion: In this retrospective study involving well-selected HCC patients, high ORR and long TTTF and OS are observed after TACE using idarubicin-loaded TANDEM. A randomized trial is needed.

Percutaneous thermal ablation of hepatocellular carcinomas located in the hepatic dome using artificial carbon dioxide pneumothorax: retrospective evaluation of safety and efficacy.

INTRODUCTION: The targeting of hepatocellular carcinomas (HCC) in the hepatic dome can be challenging during percutaneous thermal ablation (PTA). The aims of this study were (1) to evaluate the safety and efficacy of PTA of HCC in the hepatic dome that cannot be visualized under US, using artificial CO2 pneumothorax and CT-guidance and (2) to compare the results with US-visible HCC located in the liver dome treated under US-guidance. MATERIALS: Over a 32-month period, 56 HCC located in the hepatic dome were extracted from a prospectively maintained database. Twenty-eight cases (US-guidance group) were treated under US-guidance, while the others (n = 28, CT-CO2 group) were treated under CT-guidance using artificial CO2 pneumothorax after lipiodol tagging of the tumor. The primary technical success and complications rates of this technique were retrospectively assessed. Local tumor progression (LTP), intrahepatic distant recurrence (IDR), local recurrence-free survival (LRFS) and overall survival (OS) were also compared between both groups. RESULTS: Primary technical success was 100% in both groups. No major complications occurred. After a median follow-up of 13.8 months (range, 1-33.4 months), LTP occurred in 10.7% (3/28) in CT-CO2 vs. 25% (7/28) in the US-guidance group (p = NS). IDR occurred in 39.3% (11/28) in CT-CO2 vs. 28.6% (8/28) in the US-guidance group (p = NS). Death occurred in 17.9% (5/28) of patients in both groups. LRFS and OS did not significantly differ using Kaplan-Meier survival estimates. CONCLUSION: CT-guided PTA after artificially induced CO2 pneumothorax is a safe and efficient technique to treat HCC located in the hepatic dome.

Challenging TIPS in Liver Transplant Recipients: The Pull-Through Technique to Address Piggyback Anastomosis.

PURPOSE: The hepatic vein access during transjugular intrahepatic portosystemic shunt (TIPS) can be challenging in liver transplant recipient patients, especially when piggyback anastomosis was performed. We described a modified technique and reviewed the clinical outcomes of TIPS in transplanted patients. MATERIALS AND METHODS: From 2015 to 2016, 8 patients with history of liver transplantation using a three-hepatic vein piggyback technique for venous anastomosis underwent a TIPS in our institution. Indications were refractory ascites (n = 7) or variceal bleeding (n = 1). When the hepatic vein access failed via the standard jugular route, a pull-through technique was used: After puncturing the right hepatic vein under ultrasound guidance, a guidewire and a vascular sheath were advanced, then the guidewire was snared in the inferior vena cava and retrieved though the jugular access, and the hepatic vein was catheterized along the guidewire. The safety and technical success rates of this technique and the clinical outcomes of the study population were retrospectively assessed. RESULTS: Seven of 8 patients (87.5%) required the pull-through technique to access a hepatic vein. No complications of the percutaneous access of the hepatic vein were found at the one-day and one-month ultrasound Doppler examinations. Among 7 patients who had refractory ascites, 3 had complete resolution of ascites (43%), and one had moderate improvement. One patient with refractory infected ascites on severe graft failure and one with massive bleeding died soon after the procedure. CONCLUSION: A pull-through technique following percutaneous puncture of a hepatic vein is a safe technique for performing a TIPS in liver transplant recipients with piggyback anastomosis complicated by acute hepatic vein angulation.

[Portal vein embolization: Present and future]. / Embolisation portale préopératoire : présent et futur.

Portal vein embolization consists of occluding a part of the portal venous system in order to achieve the hypertrophy of the non-embolized liver segments. This technique is used during the preoperative period of major liver resection when the future remnant liver (FRL) volume is insufficient, exposing to postoperative liver failure, main cause of death after major hepatectomy. Portal vein embolization indication depends on the FRL, commonly assessed by its volume. Nowadays, FRL function evaluation seems more relevant and can be measured by 99mTc labelled mebrofenin scintigraphy. Portal vein embolization procedure is mostly performed with percutaneous trans-hepatic access by using ultrasonography guidance and consists of embolic agent injection, such as cyanoacrylate, in the targeted portal vein branches with fluoroscopic guidance. It is a safe and well-tolerated technique, with extremely low morbi-mortality. Portal vein embolization leads to sufficient FRL hypertrophy in about 80% of patients, allowing them to undergo surgery from which they were initially rejected. The two main reasons of non-resection are tumor progression (≈15% of cases) and FRL insufficient hypertrophy (≈5% of cases). When portal vein embolization is not enough to obtain adequate FRL regeneration, hepatic vein embolization may potentiate its effect (liver venous deprivation technique).

Extended liver venous deprivation before major hepatectomy induces marked and very rapid increase in future liver remnant function.

OBJECTIVE: The aim of this study was to assess the safety and efficacy of extended liver venous deprivation (eLVD), i.e. combination of right portal vein embolisation and right (accessory right) and middle hepatic vein embolisation before major hepatectomy for future remnant liver (FRL) functional increase. METHODS: eLVD was performed in non-cirrhotic patients referred for major hepatectomy in a context of small FRL (baseline FRL <25% of the total liver volume or FRL function <2.69%/min/m2). All patients underwent 99mTc-mebrofenin hepatobiliary scintigraphy (HBS) and computed tomographic evaluations. RESULTS: Ten consecutive patients underwent eLVD before surgery for liver metastases (n = 8), Klatskin tumour (n = 1) and gallbladder carcinoma (n = 1). FRL function increased by 64.3% (range = 28.1-107.5%) at day 21. In patients with serial measurements, maximum FRL function was at day 7 (+65.7 ± 16%). The FRL volume increased by +53.4% at 7 days (+25 ± 8 cc/day). Thirty-one days (range = 22-45 days) after eLVD, 9/10 patients were resected. No post-hepatectomy liver failure was reported. Two grade II and one grade III complications (Dindo-Clavien classification) occurred. No patient died with-in 90 days following surgery. CONCLUSIONS: eLVD is safe and provides a marked and very rapid increase in liver function, unprecedented for an interventional radiology procedure. KEY POINTS: • eLVD is safe • eLVD provides a marked and very rapid increase in liver function • After eLVD, the FRL-F increased by 64.3% (28.1-107.5%) at day 21 • After eLVD, the maximum FRL-F was obtained at day 7 (+65.7 ± 16%) • After eLVD, the FRL volume increased by +53.4% at 7 days (+25 ± 8 cc/day).

Interventional oncology for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and is increasing in incidence. The overall prognosis of patients with liver cancer is poor. The Barcelona Clinic Liver Cancer (BCLC) classification in 5 stages is endorsed by European Association for the Study of the Liver (EASL) and American Association for the Study of Liver Disease (AASLD). This classification is recommended for treatment allocation. Because a small proportion of patients are suitable for curative surgical treatment, various locoregional therapies are widely used to manage patients with HCC. The image-guided therapies, also called interventional radiology or interventional oncology (IO) techniques consisted in percutaneous or endovascular approach. This article reviews the different IO treatments available in HCC patients and the strength of the data.

MR imaging of locally advanced low rectal cancer: Relationships between imaging findings and the pathological tumor regression grade.

BACKGROUND: To evaluate the relationship between MR measurements and the pathological tumor regression grade (pTRG). METHODS: Two radiologists independently reviewed the pre- and postchemoradiation therapy (CRT) rectal MR images of 73 consecutive patients with locally advanced low rectal cancer who underwent neoadjuvant CRT and subsequent surgery and measured tumor diameter, area, signal intensity (SI). The percentage reduction rate for each parameter was calculated. The absolute SI ratio reduction rate was defined as the absolute value of the SI ratio reduction rate. The Kruskal-Wallis test and multivariate analysis were performed to assess the correlation between each parameter and the pTRG. Receiver operating characteristic (ROC) curves were plotted for predicting favorable regression outcomes (pTRG 3-4). RESULTS: In multivariate analysis, the absolute SI ratio reduction rate was a significant predictor of pTRG for both radiologists. Area under the ROC curve (Az) values were 0.77-0.709 for diameter reduction rate, 0.757-0.694 for area, 0.652-0.648 for the SI ratio, 0.736-0.837 for the absolute SI ratio. CONCLUSION: The absolute SI ratio reduction rate was significantly associated with pTRG and predicted favorable responses to CRT. Measurement of the diameter reduction rate is convenient and reliable in predicting favorable responses.

Incidental pancreatic cysts: natural history and diagnostic accuracy of a limited serial pancreatic cyst MRI protocol.

OBJECTIVES: To examine the natural history of incidentally detected pancreatic cysts and whether a simplified MRI protocol without gadolinium is adequate for lesion follow-up. METHODS: Over a 10-year period, 301-patients with asymptomatic pancreatic cysts underwent follow-up (45 months ± 30). The magnetic resonance imaging (MRI) protocol included axial, coronal T2-weighted images, MR cholangiopancreatographic and fat suppressed T1-weighted sequences before and after gadolinium. Three radiologists independently reviewed the initial MRI, the follow-up studies using first only unenhanced images, then secondly gadolinium-enhanced-sequences. Lesion changes during follow-up were recorded and the added value of gadolinium-enhanced sequences was determined by classifying the lesions into risk categories. RESULTS: Three hundred and one patients (1,174 cysts) constituted the study population. Only 35/301 patients (12 %) showed significant lesion change on follow-up. Using multivariate analysis the only independent factor of lesion growth (OR = 2.4; 95 % CI, 1.7-3.3; P < 0.001) and mural nodule development (OR = 1.9; 95 % CI, 1.1-3.4, P = 0.03) during follow-up was initial lesion size. No patient with a lesion initial size less than 2 cm developed cancer during follow-up. Intra-observer agreement with and without gadolinium enhancement ranged from 0.86 to 0.97. After consensus review of discordant cases, gadolinium-enhanced sequences demonstrated no added value. CONCLUSION: Most incidental pancreatic cystic lesions did not demonstrate change during follow-up. The addition of gadolinium-enhanced-sequences had no added-value for risk assignment on serial follow-up. KEY POINTS: Significant growth of pancreatic cysts occurred in a minority of patients only. No lesion <2 cm demonstrated any change during the first year of follow-up. Intra-observer agreement between MR pancreatic protocols with and without gadolinium was excellent. Gadolinium application had limited value for follow-up of asymptomatic pancreatic cystic lesions.