Outcomes of Surgical Resection after Radioembolization for Hepatocellular Carcinoma

New frontiers in liver resection for hepatocellular carcinoma

Liver resection is one of the main curative options for early hepatocellular carcinoma (HCC) in patients with cirrhosis and is the treatment of choice in non-cirrhotic patients. However, careful patient selection is required to balance the risk of postoperative liver failure and the potential benefit on long-term outcomes. In the last decades, improved surgical techniques and perioperative management, as well as better patient selection, have enabled the indications for liver resection to be expanded. In this review, we aim to describe the main indications for liver resection in the management of HCC, its role compared to percutaneous ablation and liver transplantation in the therapeutic algorithm, as well as the recent advances in liver surgery that could be used to improve the prognosis of patients with HCC.

Locoregional Therapy Approaches for Hepatocellular Carcinoma: Recent Advances and Management Strategies

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and third leading cause of cancer-related mortality worldwide. While surgical resection and transplantation are the standard first-line treatments for early-stage HCC, most patients do not fulfill criteria for surgery. Fortunately, catheter-directed and percutaneous locoregional approaches have evolved as major treatment modalities for unresectable HCC. Improved outcomes have been achieved with novel techniques which can be employed for diverse applications ranging from curative-intent for small localized tumors, to downstaging or bridging to resection and transplantation for early and intermediate disease, and locoregional control and palliation for advanced disease. This review explores recent advances in liver-directed techniques for HCC including bland transarterial embolization, chemoembolization, radioembolization, and ablative therapies, with a focus on patient selection, procedural technique, periprocedural management, and outcomes.

The safety of hepatectomy after transarterial radioembolization: Single institution experience and review of the literature

BACKGROUND AND OBJECTIVES

The liver is a frequent site of malignancy, both primary and metastatic. The treatment goal of patients with liver cancer may include transarterial radioembolization (TARE). There are limited reports on the safety of hepatectomy following TARE. Our study's purpose is to review patients who have received TARE followed by hepatectomy.

METHODS

A retrospective study was performed on patients diagnosed with any liver cancer from 2013 to 2019 who underwent TARE followed by hepatectomy. Postoperative complications were prospectively collected. Descriptive statistics and the Kaplan-Meier test were used to assess survival outcomes.

RESULTS

Twelve patients were treated with a TARE followed by a hepatectomy (nine with ≥4 segments resected). Diagnoses included: six HCC, four cholangiocarcinoma, one metastatic neuroendocrine tumor, and one metastatic colorectal cancer. There were no 90-day post-hepatectomy mortalities and the overall morbidity was 66% (16% severe ≥MAGS 3). Hepatectomy-specific complications after hepatectomy included two (16%) bile leaks and no post-hepatectomy liver failures. The median recurrence free survival was 26 months. Overall survival at 1-year was 78% and at 3 years was 47%.

CONCLUSIONS

Our results support the safety of hepatectomy in select patients after TARE. Additional comparison to patients who receive hepatectomy as a first-line treatment for liver cancers should be investigated.

Establishment and validation of a risk prediction model in patients with hepatocellular carcinoma treated with transarterial radioembolization

BACKGROUND/AIMS

Few studies have reported the treatment outcomes of transarterial radioembolization (TARE) using yttrium-90 (Y) for hepatocellular carcinoma (HCC). We established and validated a new risk prediction model for patients with HCC treated with TARE.

METHODS

Between 2010 and 2017, 113 and 35 patients with intrahepatic HCC treated with TARE were selected for the training and validation cohorts, respectively. The modified response evaluation criteria in solid tumors (mRECIST) were used for response evaluation.

RESULTS

In the training cohort, the median age was 64.1 years (92 males and 21 females) and the mean survival after TARE was 50.3 months. The cumulative survival rates at six and 12 months were 92.0 and 84.0%, respectively. A new risk prediction model for patients with HCC treated with TARE (Y-scoring system) was established from the training cohort using five independent baseline variables [serum albumin < 3.5 g/dL, hazard ratio = 5.446; alpha-fetoprotein > 200 ng/mL (hazard ratio = 5.071); tumor number ≥ 3 (hazard ratio = 2.933); portal vein thrombosis (hazard ratio = 4.915); and hepatic vein invasion (hazard ratio = 8.500)] and two on-treatment variables [no des-gamma-carboxy prothrombin response (hazard ratio = 15.346) and progressive disease at three months (hazard ratio = 4.154)] for mortality (all P < 0.05). The predictive accuracy of the Y-scoring system was acceptable to predict six [area under the curve (AUC) = 0.845], nine (AUC = 0.868), and 12-month mortality (AUC = 0.886) (all P < 0.05). The predictive accuracy of the system was similarly maintained in the validation cohort (AUC 0.737-0.901 at 6-12 months).

CONCLUSION

Our new risk prediction model can be used to stratify different prognoses in patients with HCC treated with TARE. Validation studies are required.

Transarterial Radioembolization for Hepatocellular Carcinoma and Hepatic Metastases: Clinical Aspects and Dosimetry Models

Transarterial radioembolization (TARE) with Yttrium-90 (⁹⁰Y) microspheres is a liver-directed therapy for primary and metastatic disease. This manuscript provides a review of the clinical literature on TARE indications and efficacy with overviews of patient-selection and toxicity. Current dosimetry models used in practice are safe, relatively simple, and easy for clinicians to use. Planning currently relies on the imperfect surrogate, ^99mTc macroaggregated albumin. Post-therapy quantitative imaging (⁹⁰Y SPECT/CT or ⁹⁰Y PET/CT) of microspheres can be used to calculate the macroscopic in vivo absorbed dose distribution. Similar to the evolution of other brachytherapy dose calculations, TARE is moving toward more patient-specific dosimetry that includes calculating and reporting nonuniform dose distributions throughout tumors and normal uninvolved liver.

Improving the Safety of Major Resection for Hepatobiliary Malignancy: Portal Vein Embolization and Recent Innovations in Liver Regeneration Strategies

PURPOSE OF REVIEW

For three decades, portal vein embolization (PVE) has been the "gold-standard" strategy to hypertrophy the anticipated future liver remnant (FLR) in advance of major hepatectomy. During this time, CT volumetry was the most common method to preoperatively assess FLR quality and function and used to determine which patients are appropriate surgical candidates. This review provides the most up-to-date methods for preoperatively assessing the anticipated FLR and summarizes data from the currently available strategies used to induce FLR hypertrophy before surgery for hepatobiliary malignancy.

RECENT FINDINGS

Functional and physiological imaging is increasingly replacing standard CT volumetry as the method of choice for preoperative FLR assessment. PVE, associating liver partition and portal vein ligation, radiation lobectomy, and liver venous deprivation are all currently available techniques to hypertrophy the FLR. Each strategy has pros and cons based on tumor type, extent of resection, presence or absence of underlying liver disease, age, performance status, complication rates, and other factors. Numerous strategies can lead to FLR hypertrophy and improve the safety of major hepatectomy. Which is best has yet to be determined.

Preparing for liver surgery with "Alphabet Soup": PVE, ALPPS, TAE-PVE, LVD and RL

Future liver remnant (FLR) size and function is a critical limiting factor for treatment eligibility and postoperative prognosis when considering surgical hepatectomy. Pre-operative portal vein embolization (PVE) has been proven effective in modulating FLR and now widely accepted as a standard of care. However, PVE is not always effective due to potentially inadequate augmentation of the FLR as well as tumor progression while awaiting liver growth. These concerns have prompted exploration of alternative techniques: associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), transarterial embolization-portal vein embolization (TAE-PVE), liver venous deprivation (LVD), and radiation lobectomy (RL). The article aims to review the principles and applications of PVE and these newer hepatic regenerative techniques.

Embolotherapeutic Strategies for Hepatocellular Carcinoma: 2020 Update

Hepatocellular carcinoma (HCC) represents a significant contributor to cancer-related morbidity and mortality with increasing incidence in both developing and developed countries. Embolotherapy as a locoregional therapeutic strategy consists of trans-arterial or “bland” embolization (TAE), trans-arterial chemoembolization (TACE), and selective internal radiotherapy (SIRT). Trans-catheter arterial therapies can be applied along all stages of HCC, either as an alternative or neoadjuvant to surgical resection/transplantation in very early and early stage HCC or as a palliative option for local disease control in unresectable and advanced stage HCC. In advanced stage HCC, SIRT did not demonstrate superiority in comparison to systemic treatment options in several recent large prospective trials, though for carefully selected patients, may confer improved tolerability with similar disease control rates. The latest embolotherapeutic techniques and literature as they pertain to the management of HCC, as well as future directions, are reviewed in this article.

Contralateral Liver Hypertrophy and Oncological Outcome Following Radioembolization with 90Y-Microspheres: A Systematic Review

Radioembolization with ⁹⁰Y-microspheres has been reported to induce contralateral liver hypertrophy with simultaneous ipsilateral control of tumor growth. The aim of the present systematic review was to summarize the evidence of contralateral liver hypertrophy and oncological outcome following unilateral treatment with radioembolization. A systematic literature search using the MEDLINE, EMBASE, and Cochrane libraries for studies published between 2008 and 2020 was performed. A total of 16 studies, comprising 602 patients, were included. The median kinetic growth rate per week of the contralateral liver lobe was 0.7% and declined slightly over time. The local tumor control was 84%. Surgical resection after radioembolization was carried out in 109 out of 362 patients (30%). Although the available data suggest that radioembolization prior to major hepatectomy is safe with a promising oncological outcome, the definitive role of radioembolization requires assessment within controlled clinical trials.

A novel microRNA signature predicts vascular invasion in hepatocellular carcinoma

Vascular invasion (VI) in hepatocellular carcinoma (HCC) is an important clinical parameter to predict survival. In this study, we collected microRNA (miRNA) expression data from HCC patients using The Cancer Genome Atlas database and identified a novel miRNA signature associated with VI. First, we categorized HCC patients into groups with or without VI (VI+ and VI-). We identified three miRNAs (miRNA-210, miRNA-10b, and miRNA-9-1) that were associated with VI according to a Kaplan-Meier analysis. This three-miRNA signature exhibited good predictive ability for VI in patients with HCC according to a receiver operating characteristic curve analysis at 1, 3, and 5 years. Patients with HCC with a high risk score exhibited a trend toward worse outcomes as determined by multivariable Cox regression and stratified analyses. This three-miRNA signature provides an accurate prediction of VI and can be used as an independent prognostic indicator for predicting VI in HCC patients.

A Pilot Study on Hepatobiliary Scintigraphy to Monitor Regional Liver Function in 90Y Radioembolization

Radioembolization is increasingly used as a bridge to resection (i.e., radiation lobectomy). It combines ipsilateral tumor control with the induction of contralateral hypertrophy to facilitate lobar resection. The aim of this pilot study was to investigate the complementary value of hepatobiliary scintigraphy (HBS) before and after radioembolization in the assessment of the future remnant liver. Methods: Consecutive patients with liver tumors who underwent HBS before and after ⁹⁰Y radioembolization were included. Regional (treated/nontreated) and whole liver function and volume were determined on HBS and CT. Changes in regional liver function and volume were correlated with the functional liver absorbed doses, determined on ⁹⁰Y PET/CT. In addition, the correlation between liver volume and function change was evaluated. Results: Thirteen patients (10 hepatocellular carcinoma, 3 metastatic colorectal carcinoma) were included. Liver function of the treated part declined after radioembolization (HBS-pre, 4.0%/min/m²; HBS-post, 1.9%/min/m²; P = 0.001), whereas the function of the nontreated part increased (HBS-pre, 1.4%/min/m²; HBS-post, 2.8%/min/m²; P = 0.009). Likewise, treated volume decreased (pretreatment, 1,118.7 cm³; posttreatment, 870.7 cm³; P = 0.003), whereas the nontreated volume increased (pretreatment, 412.7 cm³; posttreatment, 577.6 cm³; P = 0.005). Bland-Altman analysis revealed a large bias (29%) between volume decrease and function decrease in the treated part and wide limits of agreement (-7.7%-65.6%). The bias between volume and function change was smaller (±6.0%) in the nontreated part of the liver, but limits of agreement were still wide (-117.9%-106.7%). Conclusion: Radioembolization induces regional changes in liver function that are accurately detected by HBS. Limits of agreement between function and volume changes were wide, showing large individual differences. This finding indicates that HBS may have a complementary role in the management of patients for radiation lobectomy.

Neoadjuvant Radiation Lobectomy As an Alternative to Portal Vein Embolization in Hepatocellular Carcinoma

Surgical resection is considered first line and potentially curative for early stage hepatocellular carcinoma. However, many patients presenting with small tumors might not qualify as candidates for surgical resection given their small future liver remnant (FLR); such patients tend to undergo neoadjuvant therapies prior to resection to minimize the risk of hepatic decompensation after major hepatic resection. While there are several techniques for inducing FLR hypertrophy, a recent approach in hepatocellular carcinoma is Y90 radiation lobectomy (RL). RL was discovered serendipitously after noticing contralateral lobar hypertrophy in patients who had ipsilateral lobar Y90 radioembolization. This is now proactively used in bridging patients to surgical resection by inducing FLR hypertrophy. In this article we discuss the evolution of RL as an alternative to portal vein embolization which has been long used to induce FLR hypertrophy, albeit mostly in metastatic liver disease.

Hepatocellular Carcinoma: Etiology and Current and Future Drugs

Hepatocellular carcinoma (HCC) is swiftly increasing in prevalence globally with a high mortality rate. The progression of HCC in patients is induced with advanced fibrosis, mainly cirrhosis, and hepatitis. The absence of proper preventive or curative treatment methods encouraged extensive research against HCC to develop new therapeutic strategies. The Food and Drug Administration-approved Nexavar (sorafenib) is used in the treatment of patients with unresectable HCC. In 2017, Stivarga (regorafenib) and Opdivo (nivolumab) got approved for patients with HCC after being treated with sorafenib, and in 2018, Lenvima (lenvatinib) got approved for patients with unresectable HCC. But, owing to the rapid drug resistance development and toxicities, these treatment options are not completely satisfactory. Therefore, there is an urgent need for new systemic combination therapies that target different signaling mechanisms, thereby decreasing the prospect of cancer cells developing resistance to treatment. In this review, HCC etiology and new therapeutic strategies that include currently approved drugs and other potential candidates of HCC such as Milciclib, palbociclib, galunisertib, ipafricept, and ramucirumab are evaluated.