Analysis of Preoperative Portal Vein Embolization Outcomes in Patients with Hepatocellular Carcinoma: A Single-Center Experience

Sequential transcatheter arterial chemoembolization and portal vein embolization before hepatectomy for the management of patients with hepatocellular carcinoma: a systematic review and meta-analysis

R0 resection is the gold standard for the treatment of hepatocellular carcinoma. However, residual liver deficiency remains a major obstacle to hepatectomy. This article aims to explore the short-term and long-term efficacy of preoperative sequential transcatheter arterial chemoembolization (TACE) and portal vein embolization (PVE) in the treatment of hepatocellular carcinoma. Multiple electronic literature databases up to February 2022 were searched. Furthermore, clinical studies comparing sequential TACE + PVE with portal vein embolization (PVE) were included. The outcomes included hepatectomy rate, overall survival, disease-free survival, overall morbidity, mortality, posthepatectomy liver failure, the percentage increase in FLR. Five studies included 242 patients who received sequential TACE + PVE and 169 patients received PVE. The sequential TACE + PVE group demonstrated more favorable results in terms of hepatectomy rate (OR = 2.37; 95% CI 1.09-5.11; P = 0.03), overall survival (HR 0.55; 95% CI 0.38 to - 0.79; P = 0.001), disease-free survival (HR 0.61; 95% CI 0.44-0.83; P = 0.002), and percentage increase in FLR (MD = 4.16%; 95% CI 1.13-7.19; P = 0.007). The pooled results did not demonstrate significant differences in overall morbidity, mortality, and posthepatectomy liver failure between the sequential TACE + PVE and PVE groups. Preoperative sequential TACE + PVE has been shown to be a safe and feasible treatment for hepatocellular carcinoma to improve resectability, and it has been shown to provide better long-term oncological outcomes than PVE.

Portal Vein Embolization: Rationale, Techniques, and Outcomes to Maximize Remnant Liver Hypertrophy with a Focus on Contemporary Strategies

Hepatectomy remains the gold standard for curative therapy for patients with limited primary or metastatic hepatic tumors as it offers the best survival rates. In recent years, the indication for partial hepatectomy has evolved away from what will be removed from the patient to the volume and function of the future liver remnant (FLR), i.e., what will remain. With this regard, liver regeneration strategies have become paramount in transforming patients who previously had poor prognoses into ones who, after major hepatic resection with negative margins, have had their risk of post-hepatectomy liver failure minimized. Preoperative portal vein embolization (PVE) via the purposeful occlusion of select portal vein branches to promote contralateral hepatic lobar hypertrophy has become the accepted standard for liver regeneration. Advances in embolic materials, selection of treatment approaches, and PVE with hepatic venous deprivation or concurrent transcatheter arterial embolization/radioembolization are all active areas of research. To date, the optimal combination of embolic material to maximize FLR growth is not yet known. Knowledge of hepatic segmentation and portal venous anatomy is essential before performing PVE. In addition, the indications for PVE, the methods for assessing hepatic lobar hypertrophy, and the possible complications of PVE need to be fully understood before undertaking the procedure. The goal of this article is to discuss the rationale, indications, techniques, and outcomes of PVE before major hepatectomy.

Prediction of left lobe hypertrophy after right lobe radioembolization of the liver using a clinical data model with external validation

In cirrhotic patients with hepatocellular carcinoma (HCC), right-sided radioembolization (RE) with Yttrium-90-loaded microspheres is an established palliative therapy and can be considered a "curative intention" treatment when aiming for sequential tumor resection. To become surgical candidate, hypertrophy of the left liver lobe to > 40% (future liver remnant, FLR) is mandatory, which can develop after RE. The amount of radiation-induced shrinkage of the right lobe and compensatory hypertrophy of the left lobe is difficult for clinicians to predict. This study aimed to utilize machine learning to predict left lobe liver hypertrophy in patients with HCC and cirrhosis scheduled for right lobe RE, with external validation. The results revealed that machine learning can accurately predict relative and absolute volume changes of the left liver lobe after right lobe RE. This prediction algorithm could help to estimate the chances of conversion from palliative RE to curative major hepatectomy following significant FLR hypertrophy.

Portal vein embolization: rationale, techniques, outcomes and novel strategies

The incidence of liver cancer has grown in the past decade, with 905,677 new cases and 830,180 deaths in 2020. According to the highest annual fatality ratio, liver cancer is the third-leading cause of cancer-related deaths worldwide. Surgical resection is the mainstay treatment for long-term survival. However, only 25% of patients are surgical candidates. Recent surgical concepts, techniques and multidisciplinary management were developed, including interventional radiology procedures that improve the management algorithm, expand the indications and limit dropouts from curative treatment. This review summarizes up-to-date information on interventional radiology in the management of liver tumors.

Systematic Reviews and Meta-Analyses of Portal Vein Embolization, Associated Liver Partition and Portal Vein Ligation, and Radiation Lobectomy Outcomes in Hepatocellular Carcinoma Patients

PURPOSE OF REVIEW

To understand portal vein embolization (PVE), associated liver partition and portal vein ligation (ALPPS) and radiation lobectomy (RL) outcomes in hepatocellular carcinoma (HCC) patients. Systematic reviews of future liver remnant (FLR) percent hypertrophy, proportion undergoing hepatectomy and proportion with major complications following PVE, ALPPS, and RL were performed by searching Ovid MEDLINE, Ovid EMBASE, The Cochrane Library, and Web of Science. Separate meta-analyses using random-effects models with assessment of study heterogeneity and publication bias were performed whenever allowable by available data.

RECENT FINDINGS

Of the 10,616 articles screened, 21 articles with 636 subjects, 4 articles with 65 subjects, and 4 articles with 195 subjects met the inclusion criteria for systematic reviews and meta-analyses for PVE, ALPPS, and RL, respectively. The pooled estimate of mean percent FLR hypertrophy was 30.9% (95%CI: 22-39%, Q = 4034.8, p < 0.0001) over 40.3 +/- 26.3 days for PVE, 54.9% (95%CI: 36-74%, Q = 73.8, p < 0.0001) over 11.1 +/- 3.1 days for ALPPS, and 29.0% (95%CI: 23-35%, Q = 56.2, p < 0.0001) over 138.5 +/- 56.5 days for RL. The pooled proportion undergoing hepatectomy was 91% (95%CI: 83-95%, Q = 43.9, p = 0.002) following PVE and 98% (95%CI: 50-100%, Q = 0.0, p = 1.0) following ALPPS. The pooled proportion with major complications was 5% (95%CI: 2-10%, Q = 7.3, p = 0.887) following PVE and 38% (95%CI: 18-63%, Q = 10.0, p = 0.019) following ALPPS. Though liver hypertrophy occurs following all three treatments in HCC patients, PVE balances effective hypertrophy with a short time frame and low major complication rate.

A comparative study of portal vein embolization versus radiation lobectomy with Yttrium-90 micropheres in preparation for liver resection for initially unresectable hepatocellular carcinoma

BACKGROUND

Portal vein embolization before liver resection is considered the therapy of choice for patients with inadequate future liver remnants. The concept of radioembolization with Yttrium-90 to achieve the same goal has limited data.

METHODS

We retrospectively compared patients who underwent portal vein embolization and Yttrium-90 lobectomy before resection of hepatocellular carcinoma in patients with chronic liver disease.

RESULTS

Seventy-three patients underwent portal vein embolization and 22 patients underwent Yttrium-90. Forty-seven percent of patients before portal vein embolization required additional procedures for tumor control, and 27% of patients after Yttrium-90 required additional procedure to mainly induce further hypertrophy. Both therapies achieved the goal of future liver remnants >40%, but the degree of hypertrophy was significantly higher in Yttrium-90 patients (63% for Yttrium-90, 36% for portal vein embolization, P < .01). Tumor response was significantly better with Yttrium-90, achieving complete response in 50% of patients. Resectability rate was higher after portal vein embolization (85% for portal vein embolization, 64% for Yttrium-90, P = .03). Tumor progression was the most common reason precluding surgery. Complete tumor control was the reason not to pursue surgery in 18% of patients after Yttrium-90.

CONCLUSION

Both preoperative portal vein embolization and Yttrium-90, increases liver resectability rates by inducing hypertrophy of future liver remnants in patients with hepatocellular carcinoma and chronic liver disease. Yttrium-90 lobectomy achieved better tumor control and provided more time to assess therapy response, optimizing the indication for surgery.

Preoperative Portal Vein Embolization for Liver Resection: An updated meta-analysis

Background: Portal vein embolization (PVE) is performed before major liver resection to increase liver volume remnant, controversy remains on the adverse effect of PVE on liver tumor patients. The current study highlighted the effect of PVE on the degree of hypertrophy of future liver remnant (FLR) and summarized PVE-related complications, aiming to provide a guideline for surgeons.

Methods: A search of current published studies on PVE was performed. Meta-analysis was conducted to assess the effect of PVE on hypertrophy of FLR and summarized PVE-related complications.

Results: 26 studies including 2335 patients were enrolled in the meta-analysis. All enrolled studies reported data regarding FLR hypertrophy rate, pooled effect size (ES) for FLR hypertrophy rate using a fixed-effect model was 0.105 (95%CI: 0.094-0.117, p=0.000), indicating PVE is favored in inducing FLR hypertrophy. Metatrim method indicated no obvious evidence of publication bias in the present meta-analysis. 247 (10.6%) patients exhibited PVE-related complications, receiving expectant treatment without affecting planned liver resection. Total 1782 patients (76%) underwent a subsequent liver resection after PVE, which is an encouraging result comparing with traditional resection rate in liver tumor patients.

Conclusions: PVE is a safe and effective procedure with a low occurrence of related complications for inducing sufficient hypertrophy of FLR in liver tumor patients, which could elevate the resection rate of liver tumor patients. Careful patient cohort selection is crucial to avoid overuse of PVE in technically resectable patients. Further multiple central clinical trials are conducive to select optimal patient cohorts and provide a guideline for surgeons.

Surgical Treatments of Hepatobiliary Cancers

Hepatobiliary cancers which include hepatocellular carcinoma (HCC) and biliary tract cancers (i.e., cholangiocarcinoma and gallbladder carcinoma) are associated with significant morbidity and mortality based on the stage of the disease at presentation. With improved screening for hepatobiliary malignancies in patients with risk factors and with widespread use of laparoscopic cholecystectomy, hepatobiliary malignancies, including incidental diagnosis of gallbladder carcinoma, are on the rise. Definitive treatment of hepatobiliary malignancies include surgical resection, ablation, and liver transplantation. However, management of these cancers is challenging due to the complex hepatobiliary anatomy and the need for meticulous perioperative management especially in patients with advanced liver disease. The management and prognosis of hepatobiliary malignancies vary widely based on the stage of presentation, with surgical options providing the possibility of definitive cure in patients presenting with early-stage disease. Surgical resection for HCC results in good outcomes if performed in ideal candidates. For patients with early HCC who are not candidates for surgical resection, ablation and liver transplantation should be considered. Similarly, surgical resection is also the definitive treatment for biliary tract cancers, and liver transplantation can be curative in selected patients with perihilar cholangiocarcinoma after neoadjuvant chemoradiotherapy. The role of routine adjuvant chemotherapy and radiotherapy is not clearly established, but adjuvant therapies can offer better outcomes in patients with advanced disease at presentation. Outcomes of surgical management of hepatobiliary cancers seem to be improving. Given the complex decision-making process involved, multidisciplinary evaluation is essential to provide and coordinate the best treatments for these patients.

Treatment Options for Early-Stage Hepatocellular Carcinoma

Patients with early stage hepatocellular carcinoma have good prognosis and are treated with curative intent. Although this cohort of patients is generally defined by limited tumor burden, good liver function, and preserved functional status, there remains utility in further stratification to optimize overall survival and limit post-operative morbidity and mortality. Transplant, resection, ablation, transarterial radioembolization, and transarterial chemoembolization, either as monotherapy or in combination, may play a crucial role in treating this cohort of patients depending on a multitude of factors. In this section, we review each treatment modality and provide general guidelines for patient selection.

The transjugular approach is a safe and effective alternative for performing portal vein embolization

To evaluate the safety and efficacy of the novel technique, transjugular portal vein embolization (TPVE).A single-center retrospective review of 18 patients (12 males and 6 females; mean age, 62 years) who underwent TPVE between January 2012 and January 2013 was conducted. The technical success rate, future liver remnant (FLR) volume, total liver volume (TLV) and FLR/TLV ratio after PVE were analyzed. Liver function, including total bilirubin (TB), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and International Normalized Ratio (INR), was assessed before and after PVE. Any complications of TPVE and liver resection after TPVE were recorded.TPVE was performed on 18 patients before right hepatic resection for both primary and secondary hepatic malignancies (10 hepatocellular carcinomas, 4 cases of colorectal liver metastasis, and 4 cholangiocarcinomas). Technical success was achieved in 100% of patients (18 of 18). The mean FRL significantly increased to 580 ± 155 mL (P < .001) after PVE. The mean FLR/TLV ratio (%) significantly increased to 34 ± 4 (P < .001) after PVE. One patient suffered septicemia after TPVE. A small number patients experienced mild to moderate abdominal pain during TPVE. No other major complications occurred after TPVE in our study. The patient who developed septicemia died 3 days after the surgery as a result of this complication and subsequent multiple organ dysfunction syndrome (MODS).Transjugular portal vein embolization is a safe, efficacious, and promising novel technique to induce hypertrophy of the FLR.

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.