Role of biopsy sampling for diagnosis of early and progressed hepatocellular carcinoma

Targeted Molecular Imaging Probes Based on Magnetic Resonance Imaging for Hepatocellular Carcinoma Diagnosis and Treatment

Hepatocellular carcinoma (HCC) is the sixth most commonly malignant tumor and the third leading cause of cancer-related death in the world, and the early diagnosis and treatment of patients with HCC is core in improving its prognosis. The early diagnosis of HCC depends largely on magnetic resonance imaging (MRI). MRI has good soft-tissue resolution, which is the international standard method for the diagnosis of HCC. However, MRI is still insufficient in the diagnosis of some early small HCCs and malignant nodules, resulting in false negative results. With the deepening of research on HCC, researchers have found many specific molecular biomarkers on the surface of HCC cells, which may assist in diagnosis and treatment. On the other hand, molecular imaging has progressed rapidly in recent years, especially in the field of cancer theranostics. Hence, the preparation of molecular imaging probes that can specifically target the biomarkers of HCC, combined with MRI testing in vivo, may achieve the theranostic purpose of HCC in the early stage. Therefore, in this review, taking MR imaging as the basic point, we summarized the recent progress regarding the molecular imaging targeting various types of biomarkers on the surface of HCC cells to improve the theranostic rate of HCC. Lastly, we discussed the existing obstacles and future prospects of developing molecular imaging probes as HCC theranostic nanoplatforms.

Hepatocellular adenomas: recent updates

Hepatocellular adenoma (HCA) is a heterogeneous entity, from both the histomorphological and molecular aspects, and the resultant subclassification has brought a strong translational impact for both pathologists and clinicians. In this review, we provide an overview of the recent updates on HCA from the pathologists’ perspective and discuss several practical issues and pitfalls that may be useful for diagnostic practice.

SPECT Imaging of Hepatocellular Carcinoma Detection by the GPC3 Receptor

The glypican-3 (GPC3) receptor is a membrane protein that is highly expressed in tumor tissues but rarely expressed in the normal liver and can be used as a target for early diagnosis of hepatocellular carcinoma (HCC). Herein, we developed a GPC3-targeted ^99mTc-labeled probe for SPECT imaging in HCC. ^99mTc-HPG was rapidly radiosynthesized within 20 min with an excellent radiochemical purity (>98%), possessing good stability. Results from in vitro cell binding assays indicated that the binding specificity of ^99mTc-HPG to GPC3-positive HepG2 cells was acceptable. For SPECT/CT imaging, the HepG2 tumors were clearly visualized with the highest tumor/muscle ratio (11.55 ± 0.54) at 1 h post-injection, and the tumor uptake of ^99mTc-HPG reduced from 2.99 ± 0.15 to 1.17 ± 0.09% ID/g in the blocking study. Convenient preparation, excellent GPC3 specificity in HCC, rapid clearance from normal organs, and good biosafety profiles of ^99mTc-HPG warrant further investigations for clinical translation.

Comparison of LI-RADS with other non-invasive liver MRI criteria and radiological opinion for diagnosing hepatocellular carcinoma in cirrhotic livers using gadoxetic acid with histopathological explant correlation

AIM

To establish the diagnostic accuracy of the Liver Imaging Reporting and Data System (LI-RADS) for hepatocellular carcinoma (HCC) and compare its performance to that of international criteria from European Assofor the Study of the Liver (EASL), Japan Society of Hepatology (JSH), Asian Pacific Association for the Study of the Liver (APASL), and Organ Procurement and Transplantation Network (OPTN), and to the reporting radiologist's overall opinion regarding the probability of a nodule being a HCC by correlating with a histological diagnosis from whole liver explants.

MATERIALS AND METHODS

The present single-centre, retrospective review selected participants based on the following criteria: adults (≥18 years) listed for liver transplantation in 2014/2015, with liver cirrhosis at the time of magnetic resonance imaging (MRI) with hepatocyte specific contrast agent, and at least one liver lesion ≥10 mm on MRI with histology from subsequent liver explant for comparison. Each lesion was assessed against international criteria and given a "radiologist opinion" score of 1-5 (1 = definitely benign, 5 = definitely HCC).

RESULTS

Total 268 patient records were reviewed, with 105 eligible lesions identified from 47 patients. Median lesion size was 15.5 mm (range 10-68 mm). Sensitivity (%), specificity (%), and positive predictive value (PPV; %) for LI-RADS LR5 was 45, 89, and 89, for LI-RADS LR4+5 + TIV was 61, 80, and 86, for EASL was 44, 86 and 86, for JSH/APASL was 64, 81, and 87, for OPTN was 36, 90, and 88, and for "radiologist impression" of probably or definitely HCC was 79, 79, and 88 respectively.

CONCLUSIONS

MRI has moderate sensitivity and good specificity for the diagnosis of HCC with considerable variation depending on criteria used. OPTN criteria have the best specificity, but low sensitivity. "Radiologist opinion" gives highest overall accuracy with increases in sensitivity and reduction in specificity when compared to the imaging criteria.

Imaging of hepatocellular carcinoma: a pilot international survey

PURPOSE

To perform an international survey on current practices in imaging-based surveillance, diagnosis, staging, and assessment of treatment response for HCC.

MATERIALS AND METHODS

Three themes were covered in this international survey: demographics of respondents and liver imaging expertise; imaging practices for screening, surveillance, diagnosis, staging, and assessment of treatment response for HCC; and diagnostic imaging systems used. Descriptive summaries were created.

RESULTS

Of 151 respondents, 22.5% were from Asia, 6.0% from Europe, 19.9% from North America, 26.5% from South America, and 25.2% from Australasia; 57.0% respondents worked in academic and 34.4% in private or mixed settings. Non-contrast ultrasound was most commonly used for screening and surveillance of HCC (90.7%), and multiphase computed tomography was used for diagnosis (96.0%). Extracellular contrast agents (69.5%) were the most commonly used MRI contrast agents and Lumason/SonoVue (31.1%) is the most commonly used contrast-enhanced ultrasound contrast agent. A majority (94.0%) of respondents use ancillary imaging features for assessment of liver lesions in at-risk patients. Usage of diagnostic imaging systems for HCC varied by region. RECIST or mRECIST criteria were most commonly used for assessing HCC treatment response (48.3%). Most respondents agreed that a standardized classification for the diagnosis of HCC is needed (68.9%) and that an atlas and lexicon would help improve inter-reader agreement (71.5%).

CONCLUSION

Practices and recommendations for imaging of HCC vary between geographical regions. Future efforts to develop a unified system should address regional differences and potential barriers for adoption of a standardized diagnostic system for HCC.

Full-Core Biopsy Systems Take Larger Liver Tissue Samples with Lower Fragmentation Rates Than Conventional Side-Notch Systems: A Randomized Trial

Background

The aim of this study was to compare the histopathological quality and physical features of the specimen of a full-core end-cut biopsy system with that of the standard side-notch system for liver biopsies.

Methods

A full-core end-cut 16G biopsy device and a standard side-notch 16G needle were used to take biopsies of unclear liver lesions. Patients were randomized in two groups of 16 patients each. The primary endpoint of this prospective study was the core length measured using a dedicated microscope imaging software. Secondary endpoints were the quality of the specimen rated by an independent pathologist unaware of the device (scale from 1 to 5; with 1 as best and 5 as worst), the core diameter (determined by the microscopic imaging software) and presence of fragmentation (evaluated by the pathologist).

Results

For the full-core (FC) and side-notch (SN) groups, the mean core length was similar with 13,599 μm and 11,570 μm (p=0.131), respectively. The quality of the specimen was significantly better in the FC-group with an average rating of 1.68 vs 2.50 (p=0.009). The fragmentation rate in the FC-group was statistically significantly lower at 2/27 (7%) than in the SN-group at 13/33 (39%) (p=0.021). The diameter in the FC-group was 1042 μm vs 930 μm in SN-group (p=0.018).

When and how should we perform a biopsy for HCC in patients with liver cirrhosis in 2018? A review

The role of liver biopsy in the diagnosis of hepatocellular carcinoma (HCC) has changed over time. The diagnostic algorithm for this tumor is nowadays mainly based on radiological imaging, relegating histology to controversial cases, in which imaging techniques cannot establish a clear-cut diagnosis. This most commonly happens in small lesions, where biopsies frequently become mandatory, or in larger hypovascularized lesions. In this case however, the histological examination may not be reliable enough to grade the lesion, as different cell clones, deriving from sequential mutations, can originate heterogeneous cell populations. The risk of complications of liver biopsy, such as tumor seeding and intra-abdominal bleeding, needs to be reconsidered in light of new scientific evidence and of the technical improvements that have been introduced. Furthermore, increasing knowledge of the immunohistochemical and molecular characteristics of hepatocellular carcinoma opens a new scenario in which biopsy may play a decisive role in defining prognosis, and even treatment, by identifying the patient populations who could most benefit from target-driven hepatocellular carcinoma treatments, and therefore improving the success rate of experimental therapies. All the above reasons suggest that, overall, the role of liver biopsy in the management of HCC needs a reappraisal.

Well-differentiated hepatocellular nodule: Making a diagnosis on biopsy and resection specimens of patients with advanced stage chronic liver disease

Guided liver biopsy is commonly employed to determine the identity of distinct hepatic nodules detected on imaging studies of patients with advanced stage chronic liver diseases. Discrimination among large regenerative nodule, dysplastic nodule and well-differentiated hepatocellular carcinoma is often difficult and relies on subtle histologic findings. Sampling is an important consideration in biopsy material, as compared to resection specimens, because the diagnostic features may be focal within the nodule. Immunohistochemical stains may be useful in distinguishing between large regenerative and dysplastic nodule on the one hand, versus early and classic hepatocellular carcinoma on the other. Ongoing research on the early lesions of hepatocarcinogenesis is enhancing our understanding of the sequential steps of this process and provides novel tools for histopathologic differential diagnosis.

Insights into the diagnosis of hepatocellular carcinomas with hepatobiliary MRI

The incidence of hepatocellular carcinomas (HCCs) has increased worldwide in line with an improved screening by high-resolution imaging of cirrhotic livers. Besides abdominal ultrasonography and computerised tomography, magnetic resonance imaging (MRI) is an important tool to detect HCCs. With commercialisation of MR hepatobiliary contrast agents that cross membrane transporters in hepatocytes or tumour cells, MRI adds new information to detect and characterise HCCs. When tumour cells lose organic anion transporting polypeptides (OATP1B1/B3) in cell membranes facing sinusoidal blood, tumours appear hypointense (decreased contrast agent concentrations) in comparison to surrounding normal or cirrhotic liver that retains OATP1B1/B3 expression. However, expression, regulation, and prognostic significance of transporter evolution along carcinogenesis are not completely known. Moreover, understanding signal intensities in focal lesions also relies on transport functions of cellular efflux transporters. This manuscript reviews all the publications that associate liver imaging with hepatobiliary contrast agents and expression of transporters. The regulation of transporters along carcinogenesis to anticipate the prognosis of focal lesions is also included.

Indications of Liver Biopsy in the Era of Noninvasive Assessment of Liver Fibrosis

BACKGROUND

Liver biopsy (LB) has been used as diagnostic modality in liver diseases (LD). Over last two decades, there has been remarkable improvement in understanding of natural history, molecular diagnostics of viral hepatitis, genetic of LD, and also limitations of LB. There is current trend in avoiding LB in the management of various LDs.

AIM

To determine utility of LB in clinical practice.

MATERIAL AND METHODS

In a prospective study, 2413 patients of LD were followed up, 219 (9%) were acute, and remaining 2194 (90.9%) were chronic LD. Patients were evaluated by biochemical parameters, virological studies, and imaging endoscopy as and when required. LB was performed in 176 (7.2%) patients when no conclusion could be drawn from the noninvasive workup. Patients with platelet count <50,000/cm(2), ascites, and overt bleeding were excluded. Patients with international normalization ratio (INR) more than 1.5 were not excluded. No prophylactic use of fresh frozen plasma and platelet transfusion was done. There was no major complication related to the procedure. Indications for LB were as follows: cryptogenic LD 38 cases, hepatitis B infection 35, suspected autoimmune hepatitis 30, mass lesion in the liver and lymphoma 29, evaluation of portal hypertension 15, elevated liver enzymes 11, hepatitis C infection 9, and drug-induced LD 4, and miscellaneous 5 cases which were primary biliary cholangitis, primary sclerosing cholangitis, cholestatic LD, sarcoidosis, and amyloidosis.

RESULTS

LB changed the diagnosis in 55 (31.2%). These were cryptogenic LD in 24 cases, portal hypertension 15, elevated liver enzymes 11, and 5 others. In remaining, LB confirmed clinical diagnosis and helped in making management decisions.

CONCLUSION

LB was required in 7.2% of patients with chronic LD. In 31.2% cases, LB changed the diagnosis. LB was a safe procedure even in presence of low platelet count and abnormal INR.