The Clinical Implications of Liver Resection Margin Size in Patients with Hepatocellular Carcinoma in Terms of Positron Emission Tomography Positivity

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.

Association of Multi-Phasic MR-Based Radiomic and Dosimetric Features with Treatment Response in Unresectable Hepatocellular Carcinoma Patients following Novel Sequential TACE-SBRT-Immunotherapy

This study aims to investigate the association of pre-treatment multi-phasic MR-based radiomics and dosimetric features with treatment response to a novel sequential trans-arterial chemoembolization (TACE) plus stereotactic body radiotherapy (SBRT) plus immunotherapy regimen in unresectable Hepatocellular Carcinoma (HCC) sub-population. Twenty-six patients with unresectable HCC were retrospectively analyzed. Radiomic features were extracted from 42 lesions on arterial phase (AP) and portal-venous phase (PVP) MR images. Delta-phase (DeltaP) radiomic features were calculated as AP-to-PVP ratio. Dosimetric data of the tumor was extracted from dose-volume-histograms. A two-sided independent Mann-Whitney U test was used to assess the clinical association of each feature, and the classification performance of each significant independent feature was assessed using logistic regression. For the 3-month timepoint, four DeltaP-derived radiomics that characterize the temporal change in intratumoral randomness and uniformity were the only contributors to the treatment response association (p-value = 0.038-0.063, AUC = 0.690-0.766). For the 6-month timepoint, DeltaP-derived radiomic features (n = 4) maintained strong clinical associations with the treatment response (p-value = 0.047-0.070, AUC = 0.699-0.788), additional AP-derived radiomic features (n = 4) that reflect baseline tumoral arterial-enhanced signal pattern and tumor morphology (n = 1) that denotes initial tumor burden were shown to have strong associations with treatment response (p-value = 0.028-0.074, AUC = 0.719-0.773). This pilot study successfully demonstrated associations of pre-treatment multi-phasic MR-based radiomics with tumor response to the novel treatment regimen.

Robotic liver resection for hepatocellular carcinoma: analysis of surgical margins and clinical outcomes from a western tertiary hepatobiliary center

This study was undertaken to determine surgical outcomes of patients undergoing robotic hepatectomy for hepatocellular carcinoma (HCC) and to investigate the correlation between tumor distance to margin and perioperative outcomes, as well as overall survival (OS). To our knowledge, this study represents the largest series of robotic liver resection for HCC in North America. We retrospectively analyzed 58 consecutive patients who underwent robotic liver resection for HCC. Patients were further stratified by tumor distance to margin (≤ 1 mm, 1.1-9.9 mm, ≥ 10 mm) and their clinical outcomes including OS were compared. A majority of patients attained a greater than 1 mm tumor distance to margin (81%). There were no differences in tumor size between patient cohorts who attained ≤ 1 mm, 1.1-9.9 mm, and ≥ 10 mm margins. There were no differences in pre-, intra-, and postoperative outcomes among the three cohorts. Cost variables of interest were also similar. OS was highest in the > 10 mm margin cohort, and this was statistically significant at 3 and 5 years. Robotic HCC resection was associated with adequate tumor distance to margin. Wide margins ≥ 10 mm are associated with the best OS.

Prognostic impact of surgical margins for hepatocellular carcinoma according to preoperative alpha-fetoprotein level

BACKGROUND

HCC are known to have satellite nodules and microvascular invasions requiring sufficient margins. An alpha-fetoprotein (AFP) level >100 ng/mL is associated with worse pathological features in HCC. In practice, large resection margins, particularly >1 cm, are infrequently retrieved on the specimens.

METHODS

397 patients from 5 centres were included from 2012 to 2017. The primary endpoint was time-to-recurrence in relation to AFP level (> or <100 ng/ml) as well as surgical margins (> or <1 cm). The secondary endpoint was overall survival (OS).

RESULTS

The median follow-up was 25 months. In Low AFP group, median time to recurrence (TTR) for patients with margins <1 cm was 36 months and for patients with margins ≥1 cm was 34 months (p = 0.756), and overall survival (OS) was not significantly different according to margins (p = 0.079). In High-AFP group, patients with margins <1 cm had a higher recurrence rate than patients with margins ≥1 cm (p = 0.016): median TTR for patients with margins <1 cm was 8 months whereas it was not reached for patients with margins ≥1 cm. Patients with margins <1 cm had a significantly worse OS compared to the patients with margins ≥1 cm (p = 0.043).

CONCLUSION

Preoperative AFP level may help determine margins to effectively treat high AFP tumours. For low-AFP tumours, margins didn't have an impact on TTR or OS.

Prognostic Impact of Surgical Margin in Hepatectomy on Patients With Hepatocellular Carcinoma: A Meta-Analysis of Observational Studies

Objective

This study aims to comprehensively evaluate the prognostic impact of the surgical margin in hepatectomy on patients diagnosed with hepatocellular carcinoma (HCC).

Methods

A comprehensive and systematic search for eligible articles published in English before July 2021 was conducted across PubMed, Cochrane Library, Web of Science, and Embase electronic databases. The overall survival (OS) and disease-free survival (DFS) were the primary endpoints.

Results

In total, 37 observational studies with 12,295 cases were included in this meta-analysis. The results revealed that a wide surgical margin (≥1 cm) was associated with better OS (hazard ration (HR), 0.70; 95% confidence interval (CI), 0.63–0.77) and DFS (HR, 0.66; 95% CI, 0.61–0.71) compared to a narrow surgical margin (<1 cm). Subgroup analyses were conducted based on median follow-up time, gender, country, hepatitis B surface antigen (HBsAg) status, tumor number, and liver cirrhosis. The prognostic benefit of a wide surgical margin was consistent in most subgroups, however, analysis of studies from Western countries showed that margin width was not associated with prognosis.

Conclusion

In summary, a surgical margin wider than 1 cm prolongs the long-term prognosis of HCC patients compared to a surgical margin narrower than 1 cm.

Prognostic value of 18F-fluorodeoxyglucose positron emission tomography in patients with small hepatocellular carcinoma treated by radiofrequency ablation

BACKGROUND

¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) uptake in hepatocellular carcinoma (HCC) is significantly associated with early recurrence and survival after curative surgical resection. However, there are no reports regarding the relationship between ¹⁸F-FDG uptake and outcomes after radiofrequency ablation (RFA). A prospective cohort study was conducted to evaluate the prognostic value of ¹⁸F-FDG positron emission tomography (PET) in HCC patients after RFA.

METHODS

A total of 121 consecutive patients with primary HCC (≤3 tumors, of diameter ≤ 3 cm) without vascular invasion on imaging were examined by ¹⁸F-FDG-PET computed tomography prior to RFA. An HCC with a component of ¹⁸F-FDG uptake visibly stronger than that of surrounding liver was defined as ¹⁸F-FDG-PET positive.

RESULTS

The median follow-up period was 1267 days. There were 110 ¹⁸F-FDG-PET negative and 11 positive tumors. The cumulative 1-year recurrence rates in the ¹⁸F-FDG negative and positive groups were 30 and 64% (P = 0.017), respectively, and cumulative 1-year metastatic recurrence rates were 6 and 36% (P < 0.001), respectively. The cumulative 5-year survival rates were 88 and 22% (P < 0.001), respectively. Multivariate analysis revealed ¹⁸F-FDG-PET positivity and tumor size as independent factors related to metastatic recurrence and survival after RFA.

CONCLUSIONS

¹⁸F-FDG-PET positivity was significantly associated with outcomes after RFA. RFA should not be readily selected as the first-line treatment for small HCC that includes a component of visually strong ¹⁸F-FDG uptake.

Impact of Surgical Margin on the Prognosis of Early Hepatocellular Carcinoma (≤5 cm): A Propensity Score Matching Analysis

Aim: The influence of surgical margin on the prognosis of patients with early solitary hepatocellular carcinoma (HCC) (≤5 cm) is undetermined.

Methods: The data of 904 patients with early solitary HCC who underwent liver resection were collected for recurrence-free survival (RFS) and overall survival (OS). Propensity score matching (PSM) was performed to balance the potential bias.

Results: Log-rank tests showed that 2 mm was the best cutoff value to discriminate the prognosis of early HCC. Liver resection with a >2 mm surgical margin distance (wide-margin group) led to better 5-year RFS and OS rate compared with liver resection with a ≤2 mm surgical margin distance (narrow-margin group) among patients both before (RFS: 59.1% vs. 39.6%, P < 0.001; OS: 85.3% vs. 73.7%, P < 0.001) and after PSM (RFS: 56.3% vs. 41.0%, P < 0.001; OS: 83.0% vs. 75.0%, P = 0.010). Subgroup analysis showed that a wide-margin resection significantly improved the prognosis of patients with microvascular invasion (RFS: P < 0.001; OS: P = 0.001) and patients without liver cirrhosis (RFS: P < 0.001; OS: P = 0.001) after PSM. Multivariable Cox regression analysis revealed that narrow-margin resection is associated with poorer RFS [hazard ratio (HR) = 1.781, P < 0.001), OS (HR = 1.935, P < 0.001], and early recurrence (HR = 1.925, P < 0.001).

Conclusions: A wide-margin resection resulted in better clinical outcomes than a narrow-margin resection among patients with early solitary HCC, especially for those with microvascular invasion and without cirrhosis. An individual strategy of surgical margin should be formulated preoperation according to both tumor factors and background liver factors.

Interaction between the tumor microenvironment and resection margin in different gross types of hepatocellular carcinoma

BACKGROUND AND AIM: There is no consensus regarding the safe resection margin in hepatocellular carcinoma (HCC). Several studies reported that different gross types require different resection margins. We investigated the changes in the tumor microenvironment (TME) in different gross types of HCC.

METHODS

We selected tumor tissue and normal tissue 1 and 2 cm away from the HCC. We analyzed the expression status of TME genes and the correlation between TME genes and the effective resection margin. We further divided the patients into two groups: group 1 included expanding and vaguely nodular types, whereas group 2 included nodular with perinodular extension, multinodular confluent, and infiltrative types.

RESULTS

Group 2 showed 27% and 45% 5-year disease-free survival (DFS) and overall survival (OS) rates, respectively. Group 2 was a significant prognostic factor for DFS and OS. In cases with a resection margin of less than 1 cm or more than 2 cm, there were no differences in recurrence and survival rate between the two groups. Group 1 patients who had a resection margin that ranged from 1 to 2 cm showed significantly better DFS and OS rates. β-Catenin and matrix metalloproteinase 9 expression was significantly decreased and that of E-cadherin was significantly increased according to the resection margin in group 1.

CONCLUSIONS

Patients with expanding and vaguely nodular HCC may safely undergo surgical resection with a narrow resection margin, and patients with the other gross types must undergo surgical resection with more than a 2-cm resection margin because of their TME conditions.

Predicting the Outcome of Transcatheter Arterial Embolization Therapy for Unresectable Hepatocellular Carcinoma Based on Radiomics of Preoperative Multiparameter MRI

BACKGROUND

In unresectable hepatocellular carcinoma (HCC), methods to predict patients at increased risk of progression are required.

PURPOSE

To investigate the feasibility of radiomics model in predicting early progression of unresectable HCC after transcatheter arterial chemoembolization (TACE) therapy using preoperative multiparametric magnetic resonance imaging (MP-MRI).

STUDY TYPE

Retrospective.

POPULATION

A total of 84 patients with BCLC B stage HCC from one medical center. According to the modified response evaluation criteria in solid tumors, patients who progressed at 6 months after TACE therapy were assigned as the progressive disease (PD) group (n = 32). Patients whose MRI was performed on four devices were divided into a training cohort (n = 67). Patients whose MRI was performed on other than the previous four devices were used as the testing set (n = 17).

FIELD STRENGTH/SEQUENCE

3.0T, 1.5T axial T₂ -weighted imaging (T₂ WI), diffusion-weighted imaging (DWI, b = 0, 500 s/mm² ), and apparent diffusion coefficient (ADC) ASSESSMENT: PD was confirmed via imaging studies with MRI. Risk factors, including age, alpha fetoprotein (AFP), size, and radiomic-related features of PD were assessed. In addition, the discrimination ability of each radiomics signature was tested on an independent testing set.

STATISTICAL TESTS

The area under the receiver-operator characteristic (ROC) curve (AUC) was used to evaluate the predictive accuracy of the radiomic signature in both the training and testing sets. The results indicated that the MP-MRI model achieved the greatest benefit.

RESULTS

In the testing set, the model based on DWI features presented an AUC of (b = 0, 0.786; b = 500, 0.729), followed by T₂ WI features (0.729) and ADC (0.714). The AUC of the MP-MRI signature was increased to 0.800 compared to any single MRI signature. The multivariate logistic analysis identified the radiomics signature as independent parameters of PD, while clinical information such as age, AFP, size, etc., had no significance in the PD group.

DATA CONCLUSION

Preoperative MP-MRI has the potential to predict the outcome of TACE therapy for unresectable HCC. In addition, these image features may be complementary to the current staging systems of HCC patients.

LEVEL OF EVIDENCE

2.

TECHNICAL EFFICACY STAGE

3. J. Magn. Reson. Imaging 2020;52:1083-1090.

Radiomics in hepatocellular carcinoma: a quantitative review

Radiomics is an emerging field which extracts quantitative radiology data from medical images and explores their correlation with clinical outcomes in a non-invasive manner. This review aims to assess whether radiomics is a useful and reproducible method for clinical management of hepatocellular carcinoma (HCC) by reviewing the strengths and weaknesses of current radiomics literature pertaining specifically to HCC. From an initial set of 48 articles recovered through database searches, 23 articles were retained to be included in this review after full screening. Among these 23 studies, 7 used a radiomics approach in magnetic resonance imaging (MRI). Only two studies applied radiomics to positron emission tomography-computed tomography (PET-CT). In the remaining 14 articles, a radiomics analysis was performed on computed tomography (CT). Eight studies dealt with the relationship between biological signatures and imaging findings, and can be classified as radiogenomic studies. For each study included in our review, we computed a Radiomics Quality Score (RQS) as proposed by Lambin et al. We found that the RQS (mean ± standard deviation) was 8.35 ± 5.38 (out of a possible maximum value of 36). Although these scores are fairly low, and radiomics has not yet reached clinical utility in HCC, it is important to underscore the fact that these early studies pave the way for the radiomics field with a focus on HCC. Radiomics is still a very young field, and is far from being mature, but it remains a very promising technology for the future for developing adequate personalized treatment as a non-invasive approach, for complementing or replacing tumor biopsies, as well as for developing novel prognostic biomarkers in HCC patients.

18F-fludeoxyglucose positron emission tomography for diagnosis of HCC: implications for therapeutic strategy in curative and non-curative approaches

Hepatocellular carcinoma (HCC) is a global health issue with increasing incidence and high mortality rate. Depending on the tumor load and extent of underlying liver cirrhosis, aggressive surgical treatment by hepatectomy or liver transplantation (LT) may lead to cure, whereas different modalities of liver-directed locoregional or systemic tumor treatments are currently available for a noncurative approach. Apart from tumor burden and grade of liver dysfunction, assessment of prognostic relevant biological tumor aggressiveness is vitally important for establishing a promising multimodal therapeutic strategy and improving the individual treatment-related risk/benefit ratio. In recent years, an increasing body of clinical evidence has been presented that ¹⁸F-fludeoxyglucose (¹⁸F-FDG) positron emission tomography (PET), which is a standard nuclear imaging device in oncology, may serve as a powerful surrogate for tumor invasiveness and prognosis in HCC patients and, thereby, impact individual decision making on most appropriate therapy concept. This review describes the currently available data on the prognostic value of ¹⁸F-FDG PET in patients with early and advanced HCC stages and the resulting implications for treatment strategy.