Methods to improve resectability of hepatocellular carcinoma

Annals of Surgical Oncology Practice Guidelines Series: Management of Primary Liver and Biliary Tract Cancers

Primary cancers of the liver and biliary tract are rare and aggressive tumors that often present with locally advanced or metastatic disease. For patients with localized disease amenable to resection, surgery typically offers the best chance at curative-intent therapy. Unfortunately, the incidence of recurrence even after curative-intent surgery remains high. In turn, patients with hepatobiliary cancers commonly require multimodality therapy including a combination of resection, systemic therapy (i.e., targeted therapy, cytotoxic chemotherapy, immunotherapy), and/or loco-regional therapies. With advancements in the field, it is crucial for surgical oncologists to remain updated on the latest guidelines and recommendations for surgical management and optimal patient selection. Given the complex and evolving nature of treatment, this report highlights the latest practice guidelines for the surgical management of hepatobiliary cancers.

The current landscape of therapies for hepatocellular carcinoma

Globally, primary liver cancer is the third leading cause of cancer-related deaths, with approximately 830 000 deaths worldwide in 2020, accounting for 8.3% of total deaths from all cancer types (1). This disease disproportionately affects those in countries with low or medium Human Development Index scores in Eastern Asia, South-Eastern Asia, and Northern and Western Africa (2). Hepatocellular carcinoma (HCC), the most common type of primary liver cancer, often develops in the background of chronic liver disease, caused by hepatitis B or C virus, non-alcoholic steatohepatitis (NASH), or other diseases that cause cirrhosis. Prognosis can vary dramatically based on number, size, and location of tumors. Hepatic synthetic dysfunction and performance status (PS) also impact survival. The Barcelona Clinic Liver Cancer (BCLC) staging system best accounts for these variations, providing a reliable prognostic stratification. Therapeutic considerations of this complex disease necessitate a multidisciplinary approach and can range from curative-intent surgical resection, liver transplantation or image-guided ablation to more complex liver-directed therapies like transarterial chemoembolization (TACE) and systemic therapy. Recent advances in the understanding of the tumor biology and microenvironment have brought new advances and approvals for systemic therapeutic agents, often utilizing immunotherapy or VEGF-targeted agents to modulate the immune response. This review will discuss the current landscape in the treatments available for early, intermediate, and advanced stage HCC.

In situ split plus portal vein ligation (ISLT) - a salvage procedure following inefficient portal vein embolization to gain adequate future liver remnant volume prior to extended liver resection

Background

Right extended liver resection is frequently required to achieve tumor-free margins. Portal venous embolization (PVE) of the prospective resected hepatic segments for conditioning segments II/III does not always induce adequate hypertrophy in segments II and III (future liver remnant volume (FLRV)) for extended right-resection. Here, we present the technique of in situ split dissection along segments II/III plus portal disruption to segments IV-VIII (ISLT) as a salvage procedure to overcome inadequate gain of FLRV after PVE.

Methods

In eight patients, FLRV was further pre-conditioned following failed PVE prior to hepatectomy (ISLT-group). We compared FLRV changes in the ISLT group with patients receiving extended right hepatectomy following sufficient PVE (PVEres-group). Survival of the ISLT-group was compared to PVEres patients and PVE patients with insufficient FLRV gain or tumor progress who did not receive further surgery (PVEnores-group).

Results

Patient characteristics and surgical outcome were comparable in both groups. The mean FLRV-to-body-weight ratio in the ISLT group was smaller than in the PVEres-group pre- and post-PVE. One intraoperative mortality due to a coronary infarction was observed for an ISLT patient. ISLT was successfully completed in the remaining seven ISLT patients. Liver function and 2-year survival of ~ 50% was comparable to patients with extended right hepatectomy after efficient PVE. Patients who received a PVE but who were not subsequently resected (PVEnores) demonstrated no survival beyond 4 months.

Conclusion

Despite extended embolization of segments I and IV-VIII, ISLT should be considered if hypertrophy was not adequate. Liver function and overall survival after ISLT was comparable to patients with trisectionectomy after efficient PVE.

Image-guided interventions in oncology

Interventional oncology, a term commonly used to indicate the minimally invasive procedures performed by interventional radiologists to diagnose and manage cancer, encompasses a broad spectrum of techniques unique to interventional radiology that have been established as a vital part of the multidisciplinary oncologic cancer care team. This article provides an updated overview of the variety of applications of image-guided procedures to distinct clinical scenarios, such as the diagnosis, treatment, and management of complications of malignancies.

Indications, limitations and maneuvers to enable extended hepatectomy: Current trends

The liver is a solid organ with a wide variety of primary benign or malignant tumors as well as metastatic lesions. Surgical resection of these tumors remains the only curative modality. Several limitations, however, do not allow the performance of these operations. This review evaluates the indications and limitations regarding these extended hepatic resections, as well as describing all the manipulations that increase the candidates for such operations. A thorough review of the literature was performed in order to define indications for extended hepatectomy, as well as to present all methods that contribute to increasing the volume of the future remnant liver. The role of portal vein ligation, portal vein embolization, two-stage hepatectomy, and in situ liver transection are evaluated in the setting of indications and results. Extended hepatectomies are a necessity due to oncological reasons. All methods developed in order to increase the volume of the remnant liver are safe and efficient. in situ liver transection is a novel and revolutionary two-step procedure for extended hepatic resections. Further clinical studies are required to estimate long-term results and the oncological basis of this technique.

The critical value of remnant liver volume-to-body weight ratio to estimate posthepatectomy liver failure in cirrhotic patients

BACKGROUND

The extensive use of major hepatectomy for liver malignancies with cirrhosis increases the risk of posthepatectomy liver failure (PHLF), which is associated with a high frequency of postoperative complications, mortality, and an increased length of hospital stay. Remnant liver volume-to-body weight ratio (RLV-BWR) is more specific than the ratio of RLV-to-total liver volume (RLV-TLV) in predicting postoperative course after major hepatectomy in normal liver. Patients having normal liver with an anticipated RLV-BWR ≤0.5% are at considerable risk for hepatic dysfunction and postoperative mortality. In the present study, the critical value of RLV-BWR after liver resection in cirrhotic liver was investigated.

PATIENTS AND METHODS

Thirty one patients who underwent hepatectomy for hepatocellular carcinoma in one medical treatment unit of West China Hospital from September 2012 to December 2012 were retrospectively enrolled in study. Volumetric measurements of TLV using computed tomography were obtained before hepatectomy. PHLF was diagnosed by the "50-50 criteria." The influence of RLV-TLV and RLV-BWR on the occurrence of PHLF was investigated, and the critical value of RLV-BWR was concluded.

RESULTS

According to the occurrence of PHLF, the patients were retrospectively divided into PHLF group and non-PHLF group. There were no statistical differences of preoperative indicators between the two groups. The intraoperative indicators including the resected liver volume, RLV-TLV, and RLV-BWR were statistically significant (P < 0.05) between the two groups. The postoperative indicators including total bilirubin (TBIL), international normalized ratio, and peritoneal drainage fluid at the third and the fifth day after surgery were statistically significant (P < 0.05) between the two groups. Area under the receiver operating characteristic curve (ROC curve) predicted by RLV-BWR to the incidence of PHLF was 0.864 (P = 0.019) with 95% confidence interval (95% CI = 0.608-0.819), and the sensitivity and specialty rate were 70% and 95%, which were more than 50% and 70%, respectively. It suggested that the critical value of RLV-BWR (1.4%) had a certain predictive value on PHLF. Area under the receiver operating characteristic curve predicted by RLV-TLV to the incidence of PHLF was 0.568 (P = 0.628) with 95% confidence interval (95% CI = 0.376-0.747), and the sensitivity and specialty rate were 42.9% and 82.6%, respectively. The sensitivity (42.9%) <50% suggested that the critical value of RLV-TLR (51%) had a poor predictive value on PHLF. According to the curve critical value 1.4% of RLV-BWR, the patients were divided into RLV-BWR ≥1.4% group and RLV-BWR <1.4% group, and the incidence of PHLF between the two groups was statistically significant (P = 0.006).

CONCLUSIONS

RLV-BWR was more specific than RLV-TLV in predicting PHLF after major hepatectomy of cirrhotic liver. Patients with an anticipated RLV-BWR <1.4% are at considerable risk for PHLF.

Role of nuclear receptor FXR in liver regeneration

Liver regeneration is a practical compensatory re-growth in response to the loss of hepatic tissue. The mechanism of liver regeneration is very complex and many cytokines, transcription factors and signaling pathways are involved in this process. The farnesoid X receptor (FXR) is a member of metabolic nuclear receptors of intracellular ligand-activated transcription factors and plays an important role in metabolism of bile acids, lipid and glucose. In addition, it has been recently reported that FXR is crucial for liver regeneration. FXR activation directly promotes liver regeneration by regulating hepatocyte proliferation and regulates synthesis and transport of bile acids to prevent the liver from injury by increased bile acids after hepatectomy. The metabolic regulation of FXR is beneficial to liver regeneration. This review focuses on the mechanism of FXR regulation of liver regeneration and targeted drugs.

Salvage parenchymal liver transection for patients with insufficient volume increase after portal vein occlusion -- an extension of the ALPPS approach

BACKGROUND

Portal vein ligation (PVL) or embolization (PVE) are standard approaches to induce liver hypertrophy of the future liver remnant (FLR) prior to hepatectomy in primarily non-resectable liver tumors. However, this approach fails in about one third of patients. Recently, the new "ALPPS" approach has been described that combines PVL with parenchymal transection to induce rapid liver hypertrophy. This series explores whether isolated parenchymal transection boosts liver hypertrophy in scenarios of failed PVL/PVE.

METHODS

A multicenter database with 170 patients undergoing portal vein manipulation to increase the size of the FLR was screened for patients undergoing isolated parenchymal transection as a salvage procedure. Three patients who underwent PVL/PVE with subsequent insufficient volume gain and subsequently underwent parenchymal liver transection as a salvage procedure were identified. Patient characteristics, volume increase, postoperative complications and outcomes were analyzed.

RESULTS

The first patient underwent liver transection 16 weeks after failed PVL with a standardized FLR (sFLR) of 30%, which increased to 47% in 7 days. The second patient showed a sFLR of 25% 28 weeks after PVL and subsequent PVE of segment IV, which increased to 41% in 7 days after transection. The third patient underwent liver partition 8 weeks after PVE with a sFLR of 19%, which increased to 37% in six days. All patients underwent a R0 resection.

CONCLUSION

Failed PVE or PVL appears to represent a good indication for the isolated parenchymal liver transection according to the newly developed ALPPS approach.