Radiologic-histological correlation of hepatocellular carcinoma treated via pre-liver transplant locoregional therapies

Development and validation of a biomarker index for HCC treatment response

BACKGROUND

Serum AFP-L3%, AFP, and DCP are useful biomarkers for HCC detection, but their utility in assessing treatment response remains unknown. We aim to evaluate the accuracy of a biomarker model in the detection of posttreatment viable tumors.

METHODS

For model derivation, recipients with HCC undergoing liver transplant from 2018 to 2022 who had biomarkers collected within 3 months before transplant were included. We developed a generalized linear model for detecting posttreatment viable tumors with the 3 biomarkers as covariates, which we termed the "LAD Score." An independent cohort of 117 patients with HCC was used for external validation.

RESULTS

Among 205 recipients of transplant, 70.2% had evidence of viable tumor on explant. The median LAD score was higher among patients with viable versus nonviable tumors (1.06 vs. 0.465, p < 0.001). The LAD score had a sensitivity of 55.6% and a specificity of 85.1% at the cutoff of 0.927, which was more accurate than imaging for detecting posttreatment viable tumors (AUROC 0.736 vs. 0.643, respectively; p = 0.045). The superior performance of the LAD score over imaging is primarily driven by its greater accuracy in detecting tumors <2 cm in diameter (AUROC of the LAD score 0.721 vs. imaging 0.595, p = 0.02). In the validation data set, the LAD score had an AUROC of 0.832 (95% CI: 0.753, 0.911) with a sensitivity of 72.5% and a specificity of 89.4% at the cutoff of 0.927.

CONCLUSIONS

Our findings suggest the utility of LAD score in treatment response assessment after locoregional therapy for HCC, particularly in detecting small tumors. A larger prospective study is in progress to validate its accuracy and evaluate its performance in recurrence monitoring.

Anti-Glycolytic Drugs in the Treatment of Hepatocellular Carcinoma: Systemic and Locoregional Options

Hepatocellular cancer (HCC) is the most common primary liver cancer and the third leading cause of cancer-related death. Locoregional therapies, including transarterial embolization (TAE: bland embolization), chemoembolization (TACE), and radioembolization, have demonstrated survival benefits when treating patients with unresectable HCC. TAE and TACE occlude the tumor's arterial supply, causing hypoxia and nutritional deprivation and ultimately resulting in tumor necrosis. Embolization blocks the aerobic metabolic pathway. However, tumors, including HCC, use the "Warburg effect" and survive hypoxia from embolization. An adaptation to hypoxia through the Warburg effect, which was first described in 1956, is when the cancer cells switch to glycolysis even in the presence of oxygen. Hence, this is also known as aerobic glycolysis. In this article, the adaptation mechanisms of HCC, including glycolysis, are discussed, and anti-glycolytic treatments, including systemic and locoregional options that have been previously reported or have the potential to be utilized in the treatment of HCC, are reviewed.

Antitumor Activity of Chitosan-Coated Iron Oxide Nanocomposite Against Hepatocellular Carcinoma in Animal Models

Hepatocellular carcinoma (HCC) is among the most prevalent and lethal cancers worldwide. Chitosan-coated iron oxide nanocomposite (Fe₃O₄/Cs) is a promising bio-nanomaterial for many biological applications. The objective of this research was to evaluate the anticancer efficacy of Fe₃O₄/Cs against HCC in animal models. Fe₃O₄ nanoparticles were prepared and added to chitosan solution; then, the mixture was exposed to gamma radiation at a dose of 20 kGy. Rats have received diethylnitrosamine (DEN) orally at a dose of 20 mg/kg body weight 5 times per week during a period of 10 weeks to induce HCC and then have received Fe₃O₄/Cs intraperitoneal injection at a dose of 50 mg/kg body weight 3 times per week during a period of 4 weeks. After the last dose of Fe₃O₄/Cs administration, animals were sacrificed. DEN induced upregulation of PI3K/Akt/mTOR and MAPK (ERK, JNK, P38) signaling pathways and inflammatory markers (TLR4, iNOS, and TNF-α). DEN also decreases cleaved caspase-3 and increases liver enzymes (ALT, AST, and GGT) activities. Administration of Fe₃O₄/Cs significantly ameliorated the above-mentioned parameters.

Evolution of Radioembolization in Treatment of Hepatocellular Carcinoma: A Pictorial Review

Transarterial radioembolization (TARE) with yttrium 90 has increasingly been performed to treat hepatocellular carcinoma (HCC). TARE was historically used as a palliative lobar therapy for patients with advanced HCC beyond surgical options, ablation, or transarterial chemoembolization, but recent advancements have led to its application across the Barcelona Clinic Liver Cancer staging paradigm. Newer techniques, termed radiation lobectomy and radiation segmentectomy, are being performed before liver resection to facilitate hypertrophy of the future liver remnant, before liver transplant to bridge or downstage to transplant, or as a definite curative treatment. Imaging assessment of therapeutic response to TARE is challenging as the intent of TARE is to deliver local high-dose radiation to tumors through microembolic microspheres, preserving blood flow to promote radiation injury to the tumor. Because of the microembolic nature, early imaging assessment after TARE cannot rely solely on changes in size. Knowledge of the evolving methods of TARE along with the tools to assess posttreatment imaging and response is essential to optimize TARE as a therapeutic option for patients with HCC. ^©RSNA, 2021.

Combining Chemistry and Engineering for Hepatocellular Carcinoma: Nano-Scale and Smaller Therapies

Primary liver cancer, or hepatocellular carcinoma (HCC), is a major worldwide cause of death from carcinoma. Most patients are not candidates for surgery and medical therapies, including new immunotherapies, have not shown major improvements since the modest benefit seen with the introduction of sorafenib over a decade ago. Locoregional therapies for intermediate stage disease are not curative but provide some benefit. However, upon close scrutiny, there is still residual disease in most cases. We review the current status for treatment of intermediate stage disease, summarize the literature on correlative histopathology, and discuss emerging methods at micro-, nano-, and pico-scales to improve therapy. These include transarterial hyperthermia methods and thermoembolization, along with microfluidics model systems and new applications of mass spectrometry imaging for label-free analysis of pharmacokinetics and pharmacodynamics.

Long-term outcomes of living donor liver transplantation after locoregional treatment for hepatocellular carcinoma: an experience from a single institute

PURPOSE

The precise role of downstaging or bridge therapy for cirrhotic patients with hepatocellular carcinoma (HCC) beyond or within the Milan criteria (MC) before living donor liver transplantation (LDLT) remains undefined.

METHODS

We conducted a single-center, retrospective cohort study of 40 cirrhotic patients with HCC who underwent LDLT from 2000 to 2018. Dynamic computed tomography images at the initial presentation and immediately before LDLT as well as the final histopathological findings were reviewed to determine whether they met or exceeded MC.

RESULTS

Overall, 29 patients underwent various pre-transplant HCC treatments, including ablation and embolization (bridge therapy, n = 20; downstaging, n = 9). Of the 9 patients who were initially beyond the MC, 4 (44.4%) were successfully downstaged to within the MC. Five patients beyond the MC immediately before LDLT demonstrated a significantly worse 5-year overall survival rate than patients within the MC (16.7% vs. 82.2%, P = 0.004), regardless of the radiological HCC stage at presentation or the final pathological tumor status. All 3 recurrent patients had HCC beyond the MC immediately before transplant and died of their disease at 13, 24, and 50 months after transplantation.

CONCLUSIONS

Successful downstaging for HCC cases beyond the MC provides similar outcomes to those within the MC at presentation, regardless of the histopathological findings.

Impact of successful local ablative bridging therapy prior to liver transplantation on long-term survival in patients with hepatocellular carcinoma in cirrhosis

Background

It has been shown that local ablative procedures enable downsizing, reduce drop-out from the waiting list and improve prognosis after liver transplantation. It is still unclear whether a response to the local ablative therapy is due to a favorable tumor biology or if a real benefit in tumor stabilization exists, particularly in complete pathological response.

Method

Data of 163 HCC patients who underwent liver transplantation were extracted from our prospectively maintained registry. We analyzed the tumor load, pre-transplant α-fetoprotein levels, child stage aside the application and success of local ablative therapies as bridging procedures before transplantation.

Results

87 patients received multiple and/or combined local therapies. In 20 cases, this resulted in a complete remission of the tumor as observed in the explant histology. The other 76 patients underwent no bridging procedure. The observed 5- and 10-year survival rates for patients with bridging were 67% and 47% and without bridging 56% and 46%, respectively. Tumor-related 10-year survival showed a statistically significant difference between both groups (81% versus 59%). In the multivariate analyses bridging, number of lesions and α-fetoprotein level showed an independent statistically significant influence on tumor-related survival in these patients.

Conclusions

Successful local ablative therapy before liver transplantation is an independent statistically significant factor in long-term tumor-related survival for patients with HCC in cirrhosis and reduces tumor recurrences.

Validation of the Liver Imaging Reporting and Data System Treatment Response Criteria After Thermal Ablation for Hepatocellular Carcinoma

Single hepatocellular carcinoma (HCC) tumors can be successfully eradicated with thermal ablation (TA). We assessed the validity of the Liver Imaging Reporting and Data System Treatment Response (LR-TR) criteria with a retrospective analysis of a single-center database of patients with small HCC tumors (<3 cm in diameter) who underwent both laparoscopic TA and liver transplantation (LT) from 2004 to 2018. Postablation MRIs were assigned LR-TR categories (nonviable, equivocal, and viable) for ablated lesions and Liver Imaging Reporting and Data System (LI-RADS) categories (probable or definite HCC) for untreated lesions. Interpretations were compared with the histopathology of the post-LT explanted liver. There were 45 patients with 81 tumors (59 ablated and 22 untreated; mean size, 2.2 cm), and 23 (39%) of the ablated tumors had viable HCC on histopathology. The sensitivity/specificity of LR-TR categories (nonviable/equivocal versus viable) of ablated tumors was 30%/99%, with a positive predictive value (PPV)/negative predictive value (NPV) of 93%/69%. The sensitivity varied with residual tumor size. The sensitivity/specificity of LI-RADS 4 and 5 diagnostic criteria at detecting new HCC was 65%/94%, respectively, with a PPV/NPV of 85%/84%. The interrater reliability (IRR) was high for LR-TR categories (90% agreement, Cohen's ĸ = 0.75) and for LI-RADS LR-4 and LR-5 diagnostic categories (91% agreement, Cohen's ĸ = 0.80). In patients with HCC <3 cm in diameter, LR-TR criteria after TA had high IRR but low sensitivity, suggesting that the LR-TR categories are precise but inaccurate. The low sensitivity may be secondary to TA's disruption in the local blood flow of the tissue, which could affect the arterial enhancement phase on MRI. Additional investigation and new technologies may be necessary to improve imaging after ablation.

Assessment of Radiofrequency Ablation Efficacy for Hepatocellular Carcinoma by Histology and Pretransplant Radiology

Radiofrequency ablation (RFA) represents a potentially curative option for early-stage hepatocellular carcinoma (HCC). This study aims at evaluating the histologic response after RFA of small HCCs arising in cirrhosis. Data were reviewed from 78 patients with de novo HCCs who were treated with RFA and subsequently transplanted. The last radiological assessment before liver transplantation (LT) was used for comparison between modified Response Evaluation Criteria in Solid Tumors (mRECIST) and histological findings. A total of 125 de novo HCCs (median diameter, 20 mm) were treated with RFA only in 92 sessions. There were 98 nodules that did not show local recurrence during follow-up (78.4%), and the remaining were retreated, except 1 because of subsequent LT. On explanted livers, complete pathological response (CPR) was observed in 61.6%, being 76.9% when <2 cm, 55.0% when 2-3 cm, and 30.8% when >3 cm. Tumors near hepatic vessels had CPR in 50% of patients versus 69.3% for tumors distant from vessels (P = 0.039). Of the 125 HCCs, 114 had available radiological assessment within a median of 3 months before LT. Complete radiological response, according to mRECIST, was observed in 77.2% of nodules before LT. The Cohen κ was 0.48 (moderate agreement). The overall accuracy was 78.1%. A total of 18 complications were recorded with only 1 graded as major. In conclusion, RFA can provide high CPR for HCC, especially in smaller tumors distant from hepatic veins or portal branches. The agreement between mRECIST and histology is only moderate. Further refinements in radiological assessment are essential to accurately assess the true effectiveness of RFA.

Parametric response mapping cut-off values that predict survival of hepatocellular carcinoma patients after TACE

PURPOSE

Parametric response mapping (PRM) is a novel image-analysis technique applicable to assess tumor viability and predict intrahepatic recurrence of hepatocellular carcinoma (HCC) patients treated with transarterial chemoembolization (TACE). However, to date, the prognostic value of PRM for prediction of overall survival in HCC patients undergoing TACE is unclear. The objective of this explorative, single-center study was to identify cut-off values for voxel-specific PRM parameters that predict the post TACE overall survival in HCC patients.

METHODS

PRM was applied to biphasic CT data obtained at baseline and following 3 TACE treatments of 20 patients with HCC tumors ≥ 2 cm. The individual portal venous phases were registered to the arterial phases followed by segmentation of the largest lesion, i.e., the region of interest (ROI). Segmented voxels with their respective arterial and portal venous phase density values were displayed as a scatter plot. Voxel-specific PRM parameters were calculated and compared to patients' survival at 1, 2, and 3 years post treatment to identify the maximal predictive parameters.

RESULTS

The hypervascularized tissue portion of the ROI was found to represent an independent predictor of the post TACE overall survival. For this parameter, cut-off values of 3650, 2057, and 2057 voxels, respectively, were determined to be optimal to predict overall survival at 1, 2, and 3 years after TACE. Using these cut points, patients were correctly classified as having died with a sensitivity of 80, 92, and 86% and as still being alive with a specificity of 60, 75, and 83%, respectively. The prognostic accuracy measured by area under the curve (AUC) values ranged from 0.73 to 0.87.

CONCLUSION

PRM may have prognostic value to predict post TACE overall survival in HCC patients.

Efficacy of loco-regional treatment for hepatocellular carcinoma prior to living donor liver transplantation: a report from a single center in Egypt

Background and aim

The number of loco-regional therapies (LRTs) for hepatocellular carcinoma (HCC) has increased dramatically during the past decade, bridging or downstaging patients on the waiting list for liver transplantation. This study aimed to analyze the outcomes of LRTs prior to living donor liver transplantation in patients with HCC.

Methods

Sixty-two HCC patients received living donor liver transplantation at Ain Shams Center for Organ Transplantation over a 2-year period. Data from 29 HCC patients were analyzed. Twenty patients (68.97%) met the Milan Criteria and 4 patients (13.8%) exceeded the Milan Criteria, but met the University of California, San Francisco Criteria. Five patients (17.2%) exceeded the University of California, San Francisco Criteria. All patients underwent preoperative LRTs. The protocol of bridging/downstaging, methods, duration of follow-up, the number of patients who were successfully downstaged before liver transplantation (LT), and their outcomes after LT were recorded.

Results

There was a decrease in the mean overall size of focal lesions (from mean 5.46 to 4.11 cm) in the last abdominal computed tomography (CT) scan after LRT (p=0.0018). Discrepancies between the radiological findings and histopathology were as follows: in 16 patients (55.17%) the CT findings were consistent with the histopathological examination of the explanted liver. Underestimated tumor stage was documented in 10 patients (34.48%), and was overestimated by CT scan findings in 3 patients (10.34%). The 1-year survival rate was 93%. No patient had HCC recurrence after median follow-up of 21 months (range 1–46 months).

Conclusion

These results encouraged tumor bridging/downstaging as a potential treatment option among carefully selected patients with HCC beyond conventional criteria for LT. Further studies on a large number of patients are necessary.

Therapies for patients with hepatocellular carcinoma awaiting liver transplantation: A systematic review and meta-analysis

Patients with hepatocellular carcinoma (HCC) who are listed for liver transplantation (LT) are often treated while on the waiting list with locoregional therapy (LRT), which is aimed at either preventing progression of HCC or reducing the measurable disease burden of HCC in order to receive increased allocation priority. We aimed to synthesize evidence regarding the effectiveness of LRT in the management of patients with HCC who were on the LT waitlist. We conducted a comprehensive search of multiple databases from 1996 to April 25, 2016, for studies that enrolled adults with cirrhosis awaiting LT and treated with bridging or down-staging therapies before LT. Therapies included transcatheter arterial chemoembolization, transarterial radioembolization, ablation, and radiotherapy. We included both comparative and noncomparative studies. There were no randomized controlled trials identified. For adults with T1 HCC and waiting for LT, there were only two nonrandomized comparative studies, both with a high risk of bias, which reported the outcome of interest. In one series, the rate of dropout from all causes at 6 months in T1 HCC patients who underwent LRT was 5.3%, while in the other series of T1 HCC patients who did not receive LRT, the dropout rate at median follow-up of 2.4 years and the progression rate to T2 HCC were 30% and 88%, respectively. For adults with T2 HCC awaiting LT, transplant with any bridging therapy showed a nonsignificant reduction in the risk of waitlist dropout due to progression (relative risk [RR], 0.32; 95% confidence interval [CI], 0.06-1.85; I² = 0%) and of waitlist dropout from all causes (RR, 0.38; 95% CI, 0.060-2.370; I² = 85.7%) compared to no therapy based on three comparative studies. The quality of evidence is very low due to high risk of bias, imprecision, and inconsistency. There were five comparative studies which reported on posttransplant survival rates and 10 comparative studies which reported on posttransplant recurrence, and there was no significant difference seen in either of these endpoints. For adults initially with stage T3 HCC who received LRT, there were three studies reporting on transplant with any down-staging therapy versus no downstaging, and this showed a significant increase in 1-year (two studies, RR, 1.11; 95% CI, 1.01-1.23) and 5-year (1 study, RR, 1.17; 95% CI, 1.03-1.32) post-LT survival rates for patients who received LRT. The quality of evidence is very low due to serious risk of bias and imprecision.

CONCLUSION

In patients with HCC listed for LT, the use of LRT is associated with a nonsignificant trend toward improved waitlist and posttransplant outcomes, though there is a high risk of selection bias in the available evidence. (Hepatology 2018;67:381-400).

Radiological response and inflammation scores predict tumour recurrence in patients treated with transarterial chemoembolization before liver transplantation

AIM

To investigate the prognostic value of the radiological response after transarterial chemoembolization (TACE) and inflammatory markers in patients affected by hepatocellular carcinoma (HCC) awaiting liver transplantation (LT).

METHODS

We retrospectively evaluated the preoperative predictors of HCC recurrence in 70 patients treated with conventional (n = 16) or doxorubicin-eluting bead TACE (n = 54) before LT. The patient and tumour characteristics, including the static and dynamic alpha-fetoprotein, neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio (PLR) measurements, were recorded. Treatment response was classified according to the modified Response Evaluation Criteria in Solid Tumours (mRECIST) and the European Association for the Study of the Liver (EASL) criteria as complete response (CR), partial response (PR), stable disease or progressive disease. After examination of the explanted livers, histological necrosis was classified as complete (100% of the cumulative tumour area), partial (50%-99%) or minimal (< 50%) and was correlated with the preoperative radiological findings.

RESULTS

According to the pre-TACE radiological evaluation, 22/70 (31.4%) and 12/70 (17.1%) patients were beyond Milan and University of San Francisco (UCSF) criteria, respectively. After TACE procedures, the objective response (CR + PR) rates were 71.4% and 70.0% according to mRECIST and EASL criteria, respectively. The agreement between the two guidelines in defining the radiological response was rated as very good both for the overall and target lesion response (weighted k-value: 0.98 and 0.93, respectively). Complete and partial histological necrosis were achieved in 14/70 (20.0%) and 28/70 (40.0%) patients, respectively. Using histopathology as the reference standard, mRECIST criteria correctly classified necrosis in 72.9% (51/70) of patients and EASL criteria in 68.6% (48/70) of cases. The mRECIST non-response to TACE [Exp(b) = 9.2, p = 0.012], exceeding UCSF criteria before TACE [Exp(b) = 4.7, p = 0.033] and a preoperative PLR > 150 [Exp(b) = 5.9, p = 0.046] were independent predictors of tumour recurrence.

CONCLUSION

The radiological response and inflammatory markers are predictive of tumour recurrence and allow the proper selection of TACE-treated candidates for LT.

Ischemia Induces Quiescence and Autophagy Dependence in Hepatocellular Carcinoma

Purpose To characterize hepatocellular carcinoma (HCC) cells surviving ischemia with respect to cell cycle kinetics, chemosensitivity, and molecular dependencies that may be exploited to potentiate treatment with transarterial embolization (TAE). Materials and Methods Animal studies were performed according to institutionally approved protocols. The growth kinetics of HCC cells were studied in standard and ischemic conditions. Viability and cell cycle kinetics were measured by using flow cytometry. Cytotoxicity profiling was performed by using a colorimetric cell proliferation assay. Analyses of the Cancer Genome Atlas HCC RNA-sequencing data were performed by using Ingenuity Pathway Analysis software. Activation of molecular mediators of autophagy was measured with Western blot analysis and fluorescence microscopy. In vivo TAE was performed in a rat model of HCC with (n = 5) and without (n = 5) the autophagy inhibitor Lys05. Statistical analyses were performed by using GraphPad software. Results HCC cells survived ischemia with an up to 43% increase in the fraction of quiescent cells as compared with cells grown in standard conditions (P < .004). Neither doxorubicin nor mitomycin C potentiated the cytotoxic effects of ischemia. Gene-set analysis revealed an increase in mRNA expression of the mediators of autophagy (eg, CDKN2A, PPP2R2C, and TRAF2) in HCC as compared with normal liver. Cells surviving ischemia were autophagy dependent. Combination therapy coupling autophagy inhibition and TAE in a rat model of HCC resulted in a 21% increase in tumor necrosis compared with TAE alone (P = .044). Conclusion Ischemia induces quiescence in surviving HCC cells, resulting in a dependence on autophagy, providing a potential therapeutic target for combination therapy with TAE. ^© RSNA, 2017 Online supplemental material is available for this article.

Comparison of hepatic MDCT, MRI, and DSA to explant pathology for the detection and treatment planning of hepatocellular carcinoma

Background/Aims

The diagnosis and treatment plan for hepatocellular carcinoma (HCC) can be made from radiologic imaging. However, lesion detection may vary depending on the imaging modality. This study aims to evaluate the sensitivities of hepatic multidetector computed tomography (MDCT), magnetic resonance imaging (MRI), and digital subtraction angiography (DSA) in the detection of HCC and the consequent management impact on potential liver transplant patients.

Methods

One hundred and sixteen HCC lesions were analyzed in 41 patients who received an orthotopic liver transplant (OLT). All of the patients underwent pretransplantation hepatic DSA, MDCT, and/or MRI. The imaging results were independently reviewed retrospectively in a blinded fashion by two interventional and two abdominal radiologists. The liver explant pathology was used as the gold standard for assessing each imaging modality.

Results

The sensitivity for overall HCC detection was higher for cross-sectional imaging using MRI (51.5%, 95% confidence interval [CI]=36.2-58.4%) and MDCT (49.8%, 95% CI=43.7-55.9%) than for DSA (41.7%, 95% CI=36.2-47.3%) (P=0.05). The difference in false-positive rate was not statistically significant between MRI (22%), MDCT (29%), and DSA (29%) (P=0.67). The sensitivity was significantly higher for detecting right lobe lesions than left lobe lesions for all modalities (MRI: 56.1% vs. 43.1%, MDCT: 55.0% vs. 42.0%, and DSA: 46.9% vs. 33.9%; all P<0.01). The sensitivities of the three imaging modalities were also higher for lesions ≥2 cm vs. <2 cm (MRI: 73.4% vs. 32.7%, MDCT: 66.9% vs. 33.8%, and DSA: 62.2% vs. 24.1%; all P<0.01). The interobserver correlation was rated as very good to excellent.

Conclusion

The sensitivity for detecting HCC is higher for MRI and MDCT than for DSA, and so cross-sectional imaging modalities should be used to evaluate OLT candidacy.

Hepatic imaging following intra-arterial embolotherapy

PURPOSE

To discuss guidelines and salient imaging findings of solid tumors treated with common intra-arterial procedures used in interventional oncology.

METHODS

A meticulous literature search of PubMed-indexed articles was conducted. Key words included "imaging + embolization," "imaging + TACE," "imaging + radioembolization," "imaging + Y90," "mRECIST," and "EASL." Representative post-treatment cross-sectional images were obtained from past cases in this institution.

RESULTS

Intra-arterial therapy (IAT) in interventional oncology includes bland embolization, chemoembolization, and radioembolization. Solid tumors of the liver are the primary focus of these procedures. Cross-sectional CT and/or MR are the main modalities used to image tumors after treatment. Traditional size-based response criteria (WHO and RECIST) alone are of limited utility in determining response to IAT; tumoral necrosis and enhancement must be considered. Specifically for HCC, the EASL and mRECIST guidelines are becoming widely adopted response criteria to assess these factors. DWI, FDG-PET, and CEUS are modalities that play an adjunctive but controversial role.

CONCLUSIONS

Radiologists must be aware that the different forms of intra-arterial therapy yield characteristic findings on cross-sectional imaging. Knowledge of these findings is integral to accurate assessment of tumor response and progression.

3D versus 2D contrast-enhanced sonography in the evaluation of therapeutic response of hepatocellular carcinoma after locoregional therapies: preliminary findings

OBJECTIVE

To investigate diagnostic performance of 3D contrast-enhanced ultrasound (CEUS) compared with 2D CEUS in the assessment of therapeutic response of hepatocellular carcinoma (HCC) treated with locoregional therapies (LRT).

MATERIALS AND METHODS

Twenty-three consecutive patients (13 men and 10 women; mean age 65.5 years) with 23 HCCs (size range 1.2-7.2 cm; mean size 2.9 ± 1.4 cm) treated by means of radiofrequency ablation (RFA n = 9), transarterial chemoembolization (TACE n = 8), combined RFA and TACE (n = 3), percutaneous alcoholization (n = 2), and wedge resection (n = 1) underwent 2D and 3D CEUS 1 month (30 ± 2 days) after treatment. Magnetic resonance (n = 17) and computed tomography (n = 6) acted as standard of reference (SOR). Two radiologists assessed the absence (complete response CR) or presence (residual tumor RT) of any nodular arterially enhancing area within or along the margin of the treated HCC.

RESULTS

Both 2D and 3D CEUS observed CR in 10/23 (43.5 %) HCCs and RT in 11/23 (47.8 %) HCCs. In 1/23 (4.3 %) HCC, RT was documented by SOR and 2D CEUS, but it was not appreciable at 3D CEUS. In 1/23 (4.3 %) HCC, the presence of peripheral residual tumor was suspected by both 2D and 3D CEUS, but it was not confirmed by SOR. No statistically significant difference between 2D and 3D CEUS in depicting either CR or RT was found (p > 0.05). Sensitivity, specificity, positive and negative predictive values, and accuracy of 3D CEUS were 91.7 % [95 % confidence interval (CI) 0.760-1.073], 90.9 % (95 % CI 0.739-1.079), 91.7, 90.9, and 91.3 %, respectively.

CONCLUSION

2D and 3D CEUS provided similar diagnostic performance in the assessment of therapeutic response of HCC treated with LRT.

Efficacy and nontarget effects of transarterial chemoembolization in bridging of hepatocellular carcinoma patients to liver transplantation: a histopathologic study

PURPOSE

To histologically evaluate the efficacy and nontarget effects induced by transarterial chemoembolization as a "bridge" treatment of hepatocellular carcinoma (HCC) before liver transplantation (LT) and its relation to patient survival.

MATERIALS AND METHODS

Between October 2003 and January 2011, 51 patients with HCC underwent LT after chemoembolization with iodized oil, small spherical particles, and carboplatin. The decision for LT was made according to national guidelines. The efficacy and nontarget effects of chemoembolization were determined histologically in explanted livers, and their impact on patients' survival after LT was analyzed.

RESULTS

A total of 126 chemoembolization procedures were performed in 51 patients; the median number of procedures per patient was three (range, one to six). The extent of HCC necrosis was less than or equal to 50% in 32% of treated HCCs, more than 50% and less than or equal to 90% in 17%, and more than 90%-99% in 14%; 38% showed complete necrosis of the lesion. The most common nontarget effects were focal necrosis of the liver parenchyma adjacent to the embolized HCC nodule (28%), intralesional (micro)abscess (26%), intralesional hemorrhage (22%), and peritumoral bile duct necrosis (12%). Based on histopathologic examination, 35% of patients had HCC that did not meet Milan criteria. None of these findings was significantly associated with patient survival after LT.

CONCLUSIONS

Transarterial chemoembolization induces histopathologically confirmed HCC necrosis with a high degree of efficacy, but histologically proven complete HCC necrosis was not predictive of survival in this cohort of patients. Although histopathologic examination revealed (clinically relevant) nontarget effects in a subset of patients, they did not impair survival.