Hypointense hepatocellular carcinomas on apparent diffusion coefficient mapping: Pathological features and metastatic recurrence after hepatectomy

Comparison of Microwave and Radiofrequency Ablation for the Treatment of Small- and Medium-Sized Hepatocellular Carcinomas in a Prospective Randomized Trial

Purpose To compare the therapeutic response and clinical outcome of CT-guided percutaneous microwave (MWA) and radiofrequency ablation (RFA) for the treatment of small- and medium-sized HCC.

Materials and Methods In this prospective trial, 50 patients with HCC were randomly assigned to MWA or RFA treatment. MRI was performed 24 h before and after ablation and subsequently in 3-month intervals. Ablation volumes, ablation durations, adverse events (AE), technique efficacy, technical success, local tumor progression (LTP), disease-free survival (DFS), intrahepatic distant recurrence (IDR), and overall survival (OS) rates were evaluated.

Results The mean ablation volume was 66.5 cm³ for MWA and 29.2  cm³ for RFA (p < 0.01). The mean ablation durations for MWA and RFA were 11.2 ± 4.0 min and 16.3 ± 4.7 min, respectively (p < 0.01). Six mild AEs were documented (p > 0.05). All treatments had a technical success rate and a technique efficacy rate of 100 % (50/50, p = 1.00). LTP within 2 years occurred in 1/25 (4 %) in the MWA group and in 4/25 (16 %) in the RFA group (p = 0.06). IDR within 2 years was 8/25 (32 %) for MWA and 14/25 (56 %) for RFA (p < 0.05). The median DFS was 24.5 months and 13.4 months for MWA and RFA, respectively (p = 0.02). The 1-, 2-, 3-year OS rates were 100 %, 80 %, 72 % in the MWA group and 72 %, 64 %, 60 % in the RFA group, respectively (p ≥ 0.14).

Conclusion The clinical outcome after MWA or RFA for HCC treatment was very similar with no significant differences in LTP or OS. However, MWA shows a trend toward better DFS with fewer IDRs than RFA.

Key Points 

Comparison of Microwave and Radiofrequency Ablation for the Treatment of Small- and Medium-Sized Hepatocellular Carcinomas in a Prospective Randomized Trial

PURPOSE

To compare the therapeutic response and clinical outcome of CT-guided percutaneous microwave (MWA) and radiofrequency ablation (RFA) for the treatment of small- and medium-sized HCC.

MATERIALS AND METHODS

In this prospective trial, 50 patients with HCC were randomly assigned to MWA or RFA treatment. MRI was performed 24 h before and after ablation and subsequently in 3-month intervals. Ablation volumes, ablation durations, adverse events (AE), technique efficacy, technical success, local tumor progression (LTP), disease-free survival (DFS), intrahepatic distant recurrence (IDR), and overall survival (OS) rates were evaluated.

RESULTS

The mean ablation volume was 66.5 cm³ for MWA and 29.2  cm³ for RFA (p < 0.01). The mean ablation durations for MWA and RFA were 11.2 ± 4.0 min and 16.3 ± 4.7 min, respectively (p < 0.01). Six mild AEs were documented (p > 0.05). All treatments had a technical success rate and a technique efficacy rate of 100 % (50/50, p = 1.00). LTP within 2 years occurred in 1/25 (4 %) in the MWA group and in 4/25 (16 %) in the RFA group (p = 0.06). IDR within 2 years was 8/25 (32 %) for MWA and 14/25 (56 %) for RFA (p < 0.05). The median DFS was 24.5 months and 13.4 months for MWA and RFA, respectively (p = 0.02). The 1-, 2-, 3-year OS rates were 100 %, 80 %, 72 % in the MWA group and 72 %, 64 %, 60 % in the RFA group, respectively (p ≥ 0.14).

CONCLUSION

The clinical outcome after MWA or RFA for HCC treatment was very similar with no significant differences in LTP or OS. However, MWA shows a trend toward better DFS with fewer IDRs than RFA.

KEY POINTS

· MWA allows for larger ablation volumes and a shorter treatment duration compared to RFA in patients with HCC.. · MWA shows a trend toward better disease-free survival and fewer intrahepatic distant recurrences compared to RFA.. · The three-year survival rates show no significant difference between the two methods..

Predicting Outcome after Percutaneous Ablation for Early-Stage Hepatocellular Carcinoma Using Various Imaging Modalities

Percutaneous ablation is a low-invasive, repeatable, and curative local treatment that is now recommended for early-stage hepatocellular carcinoma (HCC) that is not suitable for surgical resection. Poorly differentiated HCC has high-grade malignancy potential. Microvascular invasion is frequently seen, even in tumors smaller than 3 cm in diameter, and prognosis is poor after percutaneous ablation. Biopsy has a high risk of complications such as bleeding and dissemination; therefore, it has limitations in determining HCC tumor malignancy prior to treatment. Advances in diagnostic imaging have enabled non-invasive diagnosis of tumor malignancy. We describe the usefulness of ultrasonography, computed tomography, magnetic resonance imaging, and 18F-fluorodeoxyglucose positron emission tomography for predicting outcome after percutaneous ablation for HCC.

Imaging prognostication and tumor biology in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy, and represents a significant global health burden with rising incidence rates, despite a more thorough understanding of the etiology and biology of HCC, as well as advancements in diagnosis and treatment modalities. According to emerging evidence, imaging features related to tumor aggressiveness can offer relevant prognostic information, hence validation of imaging prognostic features may allow for better noninvasive outcomes prediction and inform the selection of tailored therapies, ultimately improving survival outcomes for patients with HCC.

Impact of apparent diffusion coefficient on prognosis of early hepatocellular carcinoma: a case control study

BACKGROUND

We investigated the usefulness of apparent diffusion coefficients (ADC) from diffusion-weighted images (DWI) obtained using magnetic resonance imaging (MRI) for prognosis of early hepatocellular carcinoma (HCC): Barcelona Clinic Liver Cancer (BCLC) stage 0 and A.

METHODS

We enrolled 102 patients who had undergone surgical resection for early HCC: BCLC stage 0 and A, and calculated their minimum ADC using DWI-MRI. We divided patients into ADC^High (n = 72) and ADC^Low (n = 30) groups, and compared clinicopathological factors between the two groups.

RESULTS

The ADC^Low group showed higher protein induced by vitamin K absence-II (PIVKA-II) levels (p = 0.02) compared with the ADC^High group. In overall survival, the ADC^Low group showed significantly worse prognosis than the ADC^High group (p < 0.01). Univariate analysis identified multiple tumors, infiltrative growth, high PIVKA-II, and low ADC value as prognostic factors. Multivariate analysis identified infiltrative growth and low ADC value as an independent prognostic factor.

CONCLUSION

ADC values can be used to estimate the prognosis of early HCC.

MRI Features for Predicting Microvascular Invasion of Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis

PURPOSE

Microvascular invasion (MVI) is an important prognostic factor in patients with hepatocellular carcinoma (HCC). However, the reported results of magnetic resonance imaging (MRI) features for predicting MVI of HCC are variable and conflicting. Therefore, this meta-analysis aimed to identify the significant MRI features for MVI of HCC and to determine their diagnostic value.

METHODS

Original studies reporting the diagnostic performance of MRI for predicting MVI of HCC were identified in MEDLINE and EMBASE up until January 15, 2020. Study quality was assessed using QUADAS-2. A bivariate random-effects model was used to calculate the meta-analytic pooled diagnostic odds ratio (DOR) and 95% confidence interval (CI) for each MRI feature for diagnosing MVI in HCC. The meta-analytic pooled sensitivity and specificity were calculated for the significant MRI features.

RESULTS

Among 235 screened articles, we found 36 studies including 4,274 HCCs. Of the 15 available MRI features, 7 were significantly associated with MVI: larger tumor size (>5 cm) (DOR = 5.2, 95% CI [3.0-9.0]), rim arterial enhancement (4.2, 95% CI [1.7-10.6]), arterial peritumoral enhancement (4.4, 95% CI [2.8-6.9]), peritumoral hypointensity on hepatobiliary phase imaging (HBP) (8.2, 95% CI [4.4-15.2]), nonsmooth tumor margin (3.2, 95% CI [2.2-4.4]), multifocality (7.1, 95% CI [2.6-19.5]), and hypointensity on T1-weighted imaging (T1WI) (4.9, 95% CI [2.5-9.6]). Both peritumoral hypointensity on HBP and multifocality showed very high meta-analytic pooled specificities for diagnosing MVI (91.1% [85.4-94.8%] and 93.3% [74.5-98.5%], respectively).

CONCLUSIONS

Seven MRI features including larger tumor size, rim arterial enhancement, arterial peritumoral enhancement, peritumoral hypointensity on HBP, nonsmooth margin, multifocality, and hypointensity on T1WI were significant predictors for MVI of HCC. These MRI features predictive of MVI can be useful in the management of HCC.

Hepatocellular carcinoma grading and recurrence prediction using T1 mapping on gadolinium-ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging

The aim of the present study was to explore the value of T₁ mapping on gadolinium-ethoxybenzyl diethylenetriamine pentaacetic (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) for grading hepatocellular carcinoma (HCC) and predicting its recurrence rate. A retrospective study was performed that included 75 patients (66 men and 9 women; mean age, 52.89 years; age range, 23-79 years) with HCC who had undergone Gd-EOB-DTPA-enhanced MRI with T₁ mapping before surgery. The T₁ relaxation time of the 81 lesions and non-tumorous liver parenchyma in 75 patients with HCC were measured before Gd-EOB-DTPA was injected and then at 5, 10 and 20 min after administration, respectively. T_{1[lesion (L)-hepatic parenchyma (H)]/H} (%) was calculated as the increment rate of the T₁ value in the lesions relative to the non-tumorous liver parenchyma. One-way analysis of variance and Spearman's correlation analysis was used to compare the differences and relationship of T₁ mapping values among the three grades of HCC. A total of 81 lesions were divided into well-differentiated HCC (grades I; n=21), moderately differentiated HCC (grades II; n=40) and poorly differentiated HCC (grades III; n=20) according to the histopathology. The T_1(L-H)/H (%) value among grades I, II and III HCC on pre-contrast results and on post-contrast results at the 5-, 10- and 20-min hepatobiliary phase (HBP) were significantly different (P<0.05), and T_1(L-H)/H (%) was correlated with the histological grade of HCC at each time point (r=0.637, r=0.554, r=0.499 and r=0.560, respectively, P<0.001). A total of 41 recurrence cases [grade I (n=5), grade II (n=23) and grade III (n=13)] were verified by imaging (CT, MRI or ultrasound) or reoperation. Patients with grade III and grade II HCC had higher recurrence rates compared with that in patients with grade I HCC (P<0.05; median recurrence times were 258 days, 605 days and undefined, respectively). According to the optimal cut-off point for the T_1(L-H)/H (%) of the three grades of HCC, patients with HCC in the low T_1(L-H)/H (%) value group (≤155.15%) had lower cumulative recurrence rates compared with that in the medium (T_1(L-H)/H (%) >155.15% and T1_(L-H)/H (%) ≤241.20%) and high (T_1(L-H)/H (%) >241.20%) value groups at the 20-min HBP (P<0.05; median recurrence times were undefined, 530 days and 447 days, respectively). These results indicate that the parameters of T₁ mapping would be beneficial for predicting the grading and recurrence of HCC.

Hepatocellular Carcinoma: Retrospective Evaluation of the Correlation Between Gadobenate Dimeglumine-Enhanced Magnetic Resonance Imaging and Pathologic Grade

OBJECTIVE

The aim of this study was to evaluate the usefulness of gadobenate dimeglumine-enhanced magnetic resonance imaging in characterizing the grade of hepatocellular carcinoma (HCC) using the signal intensity (SI) of the erector spinae as internal reference.

MATERIALS AND METHODS

Clinical data of 40 patients (a total of 44 lesions) confirmed by pathology for HCC were retrospectively reviewed. Gadobenate dimeglumine-enhanced magnetic resonance imaging was performed in all patients, and SI of lesions (SIles), liver parenchyma around the lesions (SIhep), erector spinae (SImus) and standard deviation of SI of the surrounding noise (SDnoi) on nonenhanced T2WI, nonenhanced T1WI, and contrast-enhanced T1WI (in both arterial and hepatobiliary phase [AP and HBP]) were measured, respectively. Contrast-to-noise ratio (CNR) were separately defined as CNR1 ([SIles - SIhep]/SDnoi) and CNR2 ([SIles - SImus]/SDnoi). Statistical analyses were performed using one-way analysis of variance, least significant difference test, logistic regression analysis, Spearman rank correlation, and receiver operating characteristic curves analysis.

RESULTS

Forty-four HCCs, including 3 well-differentiated HCCs, 26 moderately differentiated HCCs, and 15 poorly differentiated (PD) HCCs, were confirmed. On logistic regression analysis, only CNR2 in the HBP was predictor of PD HCCs (P = 0.015, odds ratio = 1.040). The size of lesions, CNR1 in the AP, CNR2 in the AP, and CNR2 in the HBP, showed significant correlations with the degree of differentiation (correlation coefficients = -0.371, 0.435, 0.503, and 0.512, respectively; P = 0.013, 0.003, 0.001, and 0.000, respectively). Contrast-to-noise ratio 2 in the HBP with the cutoff of less than 4.56 could distinguish moderately differentiated HCCs from PD HCC with the sensitivity and specificity of 84.6% and 60.0%, respectively.

CONCLUSIONS

Relatively low arterial enhancement and low CNR2 value in the HBP are predictive for poor histological grade of HCCs.