Implication of microscopic and macroscopic vascular invasion for liver resection in patients with hepatocellular carcinoma

A patient alive without disease 32 months after conversion surgery following lenvatinib treatment for hepatocellular carcinoma with a tumor thrombus originating in the middle hepatic vein and reaching the right atrium via the suprahepatic vena cava: a case report

Conversion surgery for initially unresectable hepatocellular carcinoma appears to be increasing in incidence since the advent of new molecular target drugs and immune checkpoint inhibitors; however, reports on long-term outcomes are limited and the prognostic relevance of this treatment strategy remains unclear. Herein, we report the case of a 75-year-old man with hepatocellular carcinoma, 108 mm in diameter, accompanied by a tumor thrombus in the middle hepatic vein that extended to the right atrium via the suprahepatic vena cava. He underwent conversion surgery after preceding lenvatinib treatment and is alive without disease 51 months after the commencement of treatment and 32 months after surgery. Just before conversion surgery, after 19 months of lenvatinib treatment, the main tumor had reduced in size to 72 mm in diameter, the tip of the tumor thrombus had receded back to the suprahepatic vena cava, and the tumor thrombus vascularity was markedly reduced. The operative procedure was an extended left hepatectomy with concomitant middle hepatic vein resection. The tumor thrombus was removed under total vascular exclusion via incision of the root of the middle hepatic vein. Histopathological examination revealed that more than half of the liver tumor and the tumor thrombus were necrotic.

Hepatocellular Carcinoma: Surgical Management and Evolving Therapies

Hepatocellular carcinoma (HCC) is the fifth most common cancer in men and the eighth most common cancer in women worldwide. It is also the second leading cause of cancer death worldwide, with 780,000 deaths in 2018. Seventy-two percent of HCC cases occur in Asia, 10% in Europe, 8% in Africa, 5% in North America, and 5% in Latin America (Singal et al. in J Hepatol 72(2):250-261, 2020 [1]).

Outcome after Resection for Hepatocellular Carcinoma in Noncirrhotic Liver-A Single Centre Study

Liver cirrhosis is the most common risk factor for the development of hepatocellular carcinoma (HCC). However, 10 to 15% of all HCC arise in a non-cirrhotic liver. Few reliable data exist on outcome after liver resection in a non-cirrhotic liver. The aim of this single-centre study was to evaluate the outcome of resection for HCC in non-cirrhotic liver (NC-HCC) and to determine prognostic factors for overall (OS) and intrahepatic recurrence-free (RFS) survival. From 2008 to 2020, a total of 249 patients were enrolled in this retrospective study. Primary outcome was OS and RFS. Radiological and pathological findings, such as tumour size, number of nodules, Tumour-, Nodes-, Metastases- (TNM) classification and vascular invasion as well as extent of surgical resection and laboratory liver function were collected. Here, 249 patients underwent liver resection for NC-HCC. In this case, 50% of patients underwent major liver resection, perioperative mortality was 6.4%. Median OS was 35.4 months (range 1-151 months), median RFS was 10.5 months (range 1-128 moths). Tumour diameter greater than three centimetres, multifocal tumour disease, vascular invasion, preoperative low albumin and increased alpha-fetoprotein (AFP) values were associated with significantly worse OS. Our study shows that resection for NC-HCC is an acceptable treatment approach with comparatively good outcome even in extensive tumours.

Recipient C7 rs9292795 genotype and the risk of hepatocellular carcinoma recurrence after orthotopic liver transplantation in a Han Chinese population

BACKGROUND

Complement component(C7) gene has been shown to influence the prognosis in Hepatocellular carcinoma (HCC) patients. The association between C7 and HCC recurrence after orthotopic liver transplantation (OLT), however, is still unknown. The purpose of this study was to evaluate whether the donor and recipient C7 gene polymorphisms are related to HCC recurrence after OLT in the Han Chinese population.

METHODS

A total of 73 consecutive patients with HCC who had undergone OLT, both donors and recipients, were involved in this research. A single nucleotide polymorphism of C7, rs9292795, was genotyped using Sequenom MassARRAY in the cohort. The expression of C7 and the association between C7 gene polymorphisms and HCC recurrence following OLT were analyzed by bioinformatics and statistical analysis, respectively.

RESULTS

As shown in database, the expression of C7 was higher in HCC tissues than that in normal tissues, and represented a worse prognosis. We also found that recipient C7 rs9292795 polymorphism, rather than the donor, was significantly associated with HCC recurrence after OLT. Multivariate logistic regression analysis confirmed that TNM stage (P = 0.001), Milan criteria (P = 0.000) and recipient rs9292795 genotype (TT vs AA/AT, P = 0.008) were independent risk factors for HCC recurrence. Furthermore, the recipient carrying AA/AT showed higher recurrence-free survival (RFS) and overall survival (OS) than that carrying TT (P < 0.05). In Cox proportional hazards model, TNM stage, recipient rs9292795 genotype, and Milan criteria were identified as independent factors for RFS and OS (P < 0.05) as well as pre-OLT serum alpha fetoprotein (AFP) level was associated with OS (P < 0.05).

CONCLUSIONS

Recipient C7 rs9292795 gene polymorphism is related to the recurrence of HCC after OLT, which may be a helpful prognostic marker for HCC patients who receive OLT.

Microvascular Invasion in HCC: The Molecular Imaging Perspective

Hepatocellular carcinoma represents the most frequent primary liver tumor; curative options are only surgical resection and liver transplantation. From 1996, Milan Criteria are applied in consideration of patients with cirrhosis and hepatocellular for liver transplantation; nonetheless, more recently, Milan Criteria have been criticized because they appear over conservative. Apart from number and size of lesions and biomarker levels, which already have been associated with poorer prognosis, overall survival and recurrence rates after transplantation are affected also by the presence of vascular invasion. Microvascular invasion suggests a poor prognosis but it is often hard to detect before transplant. Diagnostic imaging and tumor markers may play an important role and become the main tools to define microvascular invasion. In particular, a possible role could be found for computed tomography, magnetic resonance imaging, and positron emission tomography. In this paper, we analyze the possible role of positron emission tomography as a preoperative imaging biomarker capable of predicting microvascular invasion in patients with hepatocellular carcinoma and thus selecting optimal candidates for liver transplantation.

Efficacy of postoperative adjuvant transcatheter arterial chemoembolization in hepatocellular carcinoma patients with microvascular invasion

AIM

To investigate the efficacy and safety of postoperative adjuvant transcatheter arterial chemoembolization (PA-TACE) in preventing tumor recurrence and improving survival in Barcelona Clinic Liver Cancer (BCLC) early (A) and intermediate (B) stage hepatocellular carcinoma (HCC) patients with microvascular invasion (MVI).

METHODS

A total of 519 BCLC A or B HCC patients treated by liver resection alone or followed by PA-TACE between January 2012 and December 2015 were studied retrospectively. Univariate and multivariate analyses were performed to investigate the risk factors for recurrence-free survival (RFS) and overall survival (OS). Multiple logistic regression was used to identify the clinicopathological characteristics associated with MVI. The rates of RFS and OS were compared among patients with or without MVI treated with liver resection alone or followed by PA-TACE.

RESULTS

Univariate and multivariate analyses demonstrated that serum AFP level > 400 ng/mL, tumor size > 5 cm, tumor capsule invasion, MVI, and major hepatectomy were risk factors for poor OS. Tumor capsule invasion, MVI, tumor size > 5 cm, HBV-DNA copies > 1 x 10⁴ IU/mL, and multinodularity were risk factors for poor RFS. Multiple logistic regression identified serum AFP level > 400 ng/mL, tumor size > 5 cm, and tumor capsule invasion as independent predictors of MVI. Both OS and DFS were significantly improved in patients with MVI who received PA-TACE as compared to those who underwent liver resection alone. Patients without MVI did not show a significant difference in OS and RFS between those treated by liver resection alone or followed by PA-TACE.

CONCLUSION

PA-TACE is a safe adjuvant intervention and can efficiently prevent tumor recurrence and improve the survival of BCLC early- and intermediate-stage HCC patients with MVI.

Molecular alterations in the carcinogenesis and progression of hepatocellular carcinoma: Tumor factors and background liver factors

Although hepatocellular carcinoma (HCC) is associated with poor prognosis worldwide, the molecular mechanisms underlying the carcinogenesis and progression of this disease remain unclear. Several tumor characteristics have previously been demonstrated to be prognostic factors of survival following hepatic resection, or the recurrence of HCC or other types of cancer. Comparisons of normal tissues and HCC tumor tissues have revealed the presence of numerous molecular alterations in HCC, including genetic and epigenetic mechanisms, particularly mutations in certain genes and DNA methylation in the promoter regions of tumor-suppressor genes. A number of studies have previously used array analysis to detect variations in the expression levels of cancer-associated genes and microRNAs, and in DNA methylation. However, an investigation of HCC tumor tissues may not determine the effect of noncancerous liver tissues (background liver) in patients with HCC. As HCC may recur multicentrically following resection, a damaged or chronically diseased HCC background liver may be considered as a pre-cancerous organ. Therefore, the influence of the background liver on HCC requires further study. Detailed studies regarding the background liver may be essential for the improved understanding of the carcinogenesis and progression of this malignancy; however only a few studies have investigated the microenvironment of the HCC background liver. The present review discusses prior molecular studies of hepatocarcinogenesis that focus on HCC and background liver tissues.

Peroxisome Proliferator-Activated Receptor γ Expression Is Inversely Associated with Macroscopic Vascular Invasion in Human Hepatocellular Carcinoma

Peroxisome proliferator-activated receptor γ (PPARγ) is a ligand-activated nuclear receptor that regulates cellular lipid and glucose metabolism and also plays an inhibitory role in various cancers. However, the role of PPARγ in hepatocellular carcinoma (HCC) remains controversial. This study aimed to investigate the prognostic value of PPARγ in HCC and its role in inhibiting tumor progression, namely, HCC cell growth, migration, and angiogenesis. Immunohistochemical PPARγ staining was examined in 83 HCC specimens to investigate the clinicopathological correlations between PPARγ expression and various parameters. The functional role of PPARγ was determined via PPARγ overexpression and knockdown in HCC cells. Patients with low HCC tissue PPARγ expression were significantly younger (p = 0.006), and exhibited more tumor numbers (p = 0.038), more macroscopic vascular invasion (MVI) (p = 0.008), and more advanced TNM (size of primary tumor, number of regional lymph nodes, and distant metastasis) stages at diagnosis (p = 0.013) than patients with high HCC tissue PPARγ expression. PPARγ knockdown increased HCC cell growth, migration, and angiogenesis, while PPARγ overexpression reduced HCC cell growth, migration, and angiogenesis. These results suggest that low PPARγ expression is an independent predictor of more MVI in HCC patients. PPARγ contributes to the suppression of HCC cell growth, migration, and angiogenesis. Therefore, PPARγ may be a therapeutic target in HCC patients.

Prognostic role of magnetic resonance imaging vs. computed tomography for hepatocellular carcinoma undergoing chemoembolization

BACKGROUND & AIMS

Computed tomography (CT) and magnetic resonance imaging (MRI) play important roles in diagnosis and staging of hepatocellular carcinoma (HCC). However, prognostic roles of radiological characteristics are not yet determined.

METHODS

Eighty-eight patients treated with chemoembolization were analysed. Radiological parameters at baseline were assessed in all patients using both dynamic CT and MRI. Treatment responses were assessed using modified RECIST 4 weeks after the first chemoembolization.

RESULTS

Gross vascular invasion (GVI), bile duct invasion, irregular tumour margin (ITM), peripheral ragged enhancement (PRE) and satellite nodules on CT or MRI were associated with non-response (stable disease or progression) after chemoembolization respectively (all P ≤ 0.05). GVI, ITM and PRE on CT or MRI were also independently associated with poor overall survival (OS) respectively (all P ≤ 0.05). Using these results, a prognostic scoring system for CT and MRI were developed; 0, absence of all three features (GVI, ITM and PRE); 1, presence of one feature; 2, presence of two features; and 3, presence of three features. After adjusting tumour size, tumour number and alpha-foetoprotein level, both CT and MRI scores were independently associated with OS (both P < 0.001). Patients with CT or MRI score ≥2 had a worse OS than those with score <2 (adjusted hazard ratios, 3.837 and 2.938 respectively). MRI-specific parameters such as signal intensity on T2- or T1-weighted images, fat signal or hyperintensity on diffusion-weighted images did not have prognostic value (all P > 0.05).

CONCLUSIONS

Radiological parameters by CT and MRI may be useful in biological characterization of tumours and prognostification for HCC treated with chemoembolization.