Morphologic Subtypes of Hepatocellular Carcinoma

An update on subtypes of hepatocellular carcinoma: From morphology to molecular

The morphologic spectrum of hepatocellular carcinoma (HCC) is quite broad. While in about one-third of cases, the neoplasms can be categorized into meaningful subtypes based on morphology, a vast majority of these neoplasms are morphologically heterogeneous. With extensive tumor profiling, data has begun to emerge which can correlate specific morphologic features with underlying molecular signatures. A true morphologic subtype not only has reproducible H & E features, further supported by specific immunohistochemical or molecular signatures, but also has specific clinical implications and prognostic associations. Eight such morphologic subtypes are recognized by the 2019 WHO classification of tumors with a few more additional subtypes described in the literature. The goal of this review is to familiarize the reader with the morphologic subtypes and elaborate on the clinical and molecular associations of these neoplasms.

Hepatocellular carcinoma: making sense of morphological heterogeneity, growth patterns, and subtypes

Hepatocellular carcinomas are not a homogenous group of tumors but have multiple layers of heterogeneity. This heterogeneity has been studied for many years with the goal to individualize care for patients and has led to the identification of numerous hepatocellular carcinoma subtypes, defined by morphology and or molecular methods. This article reviews both gross and histological levels of heterogeneity within hepatocellular carcinoma, with a focus on histological findings, reviewing how different levels of histological heterogeneity are used as building blocks to construct morphological hepatocellular carcinoma subtypes. The current best practice for defining a morphological subtype is outlined. Then, the definition for thirteen distinct hepatocellular carcinoma subtypes is reviewed. For each of these subtypes, unresolved issues regarding their definitions are highlighted, including recommendations for these problematic areas. Finally, three methods for improving the research on hepatocellular carcinoma subtypes are proposed: (1) Use a systemic, rigorous approach for defining hepatocellular carcinoma subtypes (four-point model); (2) Once definitions for a subtype are established, it should be followed in research studies, as this common denominator enhances the ability to compare results between studies; and (3) Studies of subtypes will be more effective when morphological and molecular results are used in synergistic and iterative study designs where the results of one approach are used to refine and sharpen the results of the other. These and related efforts to better understand heterogeneity within hepatocellular carcinoma are the most promising avenue for improving patient care by individualizing patient care.

A rare histologic subtype of hepatocellular carcinoma, sarcomatoid hepatocellular carcinoma: report of a case

Worldwide, primary liver cancer is the fourth leading cause of cancer mortality. Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer. Sarcomatoid hepatocellular carcinoma (SHC) is a rare subtype of HCC with conventional HCC admixed with areas with sarcomatoid morphology. SHC is an aggressive, rapidly growing tumor with unfavorable prognosis. Pedunculated SHC is an uncommon presentation of SHC. Due to its rarity, much remains unknown about the etiopathogenesis, molecular underpinnings, and treatment of SHC. We present a case of an exophytic SHC arising in a background of cirrhosis in an older adult. A resection was performed, but the patient subsequently developed multiple additional intrahepatic metastatic lesions necessitating further treatment with chemotherapy.

Hepatocellular carcinoma: Clinicopathologic associations amidst marked phenotypic heterogeneity

BACKGROUND

Hepatocellular carcinoma (HCC) is characterized by marked phenotypic and molecular heterogeneity. Clinico-morphologic phenotypes and associations are important surrogate markers of molecular aberrations; therefore have immense relevance for targeted therapy. There is paucity of published literature on critical analysis of HCC heterogeneity and morphological alliance.

AIMS

To assess the heterogeneity and dominance of histomorphological features, and to explore clinicopathological associations in HCC.

METHODS

Retrospective cross-sectional study of 217 HCC tissue specimens was performed for the assessment of prevalence of major histological patterns, cytological features, and clinicopathological correlation.

RESULTS

Homogeneous architecture with a single dominant histological pattern was a rarity. Single pattern constituting ≥50 % of the tumour was found in less than 1/5th of the cases. Macrotrabecular HCC represented 9.2 % of cases. The simultaneous presence of 2-3 patterns or atypical variants and/ or cytological characteristics was recorded in 25 % and 30 % respectively. Significant clinicopathological associations: Pseudoglandular with microtrabecular pattern-cholestasis, showed better differentiation and early-stage; macrotrabecular pattern frequently occurred with pleomorphic giant cells, higher tumour stage, higher AFP levels; solid pattern often showed clear cells. Noticeable mutual exclusions were MD bodies with microtrabecular and pseudoglandular patterns; Compact pattern with neutrophilic clusters and cholestasis. Larger tumours were significantly more heterogeneous; however, heterogeneity did not correlate with outcome CONCLUSIONS: HCC displays immense heterogeneity with an amalgamation of different histomorphological patterns and features; nevertheless, there are certain reproducible associations and omissions. Tumor biopsies agree fairly well with large specimens. Characterization of phenotypic heterogeneity, dominance, associations, and exclusions in individual patients provides vital information.

Hepatocellular Carcinoma: Role of Pathology in the Era of Precision Medicine

Hepatocellular carcinoma (HCC) is a morphologically heterogeneous tumor with variable architectural growth patterns and several distinct histologic subtypes. Large-scale attempts have been made over the past decade to identify targetable genomic alterations in HCC; however, its translation into clinical personalized care remains a challenge to precision oncology. The role of pathology is no longer limited to confirmation of diagnosis when radiologic features are atypical. Pathology is now in a position to predict the underlying molecular alteration, prognosis, and behavior of HCC. This review outlines various aspects of histopathologic diagnosis and role of pathology in cutting-edge diagnostics of HCC.

Achievement of complete response to nivolumab in a patient with advanced sarcomatoid hepatocellular carcinoma: A case report

BACKGROUND

Sarcomatoid hepatocellular carcinoma (SHC) is a rare subtype of hepatocellular carcinoma (HCC), with a high recurrence rate after surgery. In addition to limited effective treatment for the advanced stage of SHC, the prognosis of patients with this malignancy is worse than that of patients with conventional HCC.

CASE SUMMARY

We present the case of a 54-year-old man with SHC who underwent radical segmental hepatectomy, which relapsed 4 mo after surgery due to lymphatic metastasis in the porta hepatis. Although a second surgery was performed, new metastasis developed in the mediastinal lymph nodes. Therefore, sorafenib and lenvatinib were sequentially administered as first- and second-line systemic therapies, respectively. However, progressive disease was confirmed based on a recurrent hepatic lesion and new metastatic lesion in the abdominal cavity. Percutaneous transhepatic cholangial drainage was performed to alleviate the biliary obstruction. Because the tumor was strongly positive for programmed death-ligand 1, the patient was started on nivolumab. Imaging studies revealed that after two cycles of immunotherapy, the metastatic lesions decreased to undetectable levels.

CONCLUSION

The patient experienced continuous complete remission for 8 mo. Immune checkpoint inhibitors are useful for the treatment of advanced SHC.

Sarcomatoid hepatocellular carcinoma mimicking hepatic abscess: A case report

RATIONALE

Primary sarcomatoid hepatocellular carcinoma (SHC) is a rare subtype of morphologic hepatocellular carcinoma reported on less than 1% of surgical pathology specimens. Herein, we report a rare case of SHC. The case in question was initially misdiagnosed as a liver abscess due to the clinical and radiological similarity between these 2 pathologies. Ultrasound(US)- and contrast-enhanced ultrasound (CEUS)- guided biopsies are helpful in making an accurate diagnosis under the appropriate biopsy area and angle of puncture.

PATIENT CONCERNS

A 56-year old male presented to our hospital with a 2-month history of dull, upper abdominal pain without radiation.

DIAGNOSES

Upon initial investigation with computed tomography, a cystic mass was found in the hepatic V segment and an infectious etiology was presumed. Further diagnostic examination with CEUS and magnetic resonance imaging suggested a hepatic abscess. However, a diagnosis of atypical intrahepatic cholangiocarcinoma was not excluded. The patient received the standard antibiotic treatment without alleviation of his symptoms. Through 3 diagnostic US-and CEUS-guided biopsies over a 3-month period, the pathological diagnosis of SHC was finally confirmed.

INTERVENTIONS

The patient was diagnosed by 3 diagnostic US-and CEUS-guided biopsies, the pathological diagnosis of SHC was finally confirmed.

OUTCOMES

Due to the delay in diagnosis, the patient was not a candidate for surgical resection, and showed dissemination of the lesion to the portal vein. Therefore, treatment with chemotherapy was initiated. After 4 courses of this regimen, tumor progression was found on enhanced magnetic resonance imaging. Therefore, the patient received immunotherapy and targeted therapy with limited response. The patient passed away 3 months later due to tumor progression.

LESSONS

A hepatic abscess should be considered as a malignant lesion when clinical symptoms do not resolve upon standard treatment. US- and CEUS- guided biopsies are helpful in making an accurate diagnosis under the appropriate biopsy area and angle of puncture.

Lymphoepithelioma-like carcinoma in liver not associated with Epstein-Barr virus: a report of 3 cases and literature review

Background

Lymphoepithelioma-like carcinoma is a rare distinctive variant of liver cancer with unique epidemiological and pathological characteristics, characterized by dense lymphocyte infiltration. It can be divided into lymphoepithelioma-like hepatocellular carcinoma and lymphoepithelioma-like intrahepatic cholangiocarcinoma. Existing research shows that the prognosis of this tumor is good. To date, only 101 cases have been reported.

Case presentation

The first patient was a 62-year-old Chinese man with hepatitis B virus infection who presented with a single lesion in the liver. The patient underwent surgical treatment and was discharged on the 4th day. The patient was diagnosed with combined lymphoepithelioma-like hepatocellular carcinoma and cholangiocarcinoma; he has been alive for 15 months. The second patient was a 63-year-old Chinese woman with right upper abdominal pain and hepatitis B virus infection. The imaging examination revealed a single lesion in the liver. The patient underwent surgical treatment and was discharged 1 week later. The patient was diagnosed with lymphoepithelioma-like hepatocellular carcinoma and was considered to have recurrence in the lymph nodes approximately 2 years after the operation. The patient underwent local radiotherapy; she has been alive for 60 months. The third patient was a 50-year-old Chinese man with hepatitis B virus infection who presented with a single lesion in the liver and two enlarged lymph nodes. The patient received liver puncture before surgery to indicate lymph node metastasis and experienced local recurrence after liver resection. The patient underwent chemotherapy and radiotherapy. The patient was diagnosed with lymphoepithelioma-like hepatocellular carcinoma. The patient was deceased at 24-month follow-up.

Conclusions

This article reports 3 cases without Epstein-Barr virus and reviews the current literature, which suggests even mixed pathological type or locally advanced cases of LELC with lymph node metastasis and postoperative recurrence should be actively treated for a longer survival period.

Optimizing small liver biopsy specimens: a combined cytopathology and surgical pathology perspective

Both fine-needle aspiration (FNA) and core needle biopsy (CNB) are widely used to obtain liver biopsy specimens, particularly from mass lesions. However, the advantages and disadvantages of FNA versus CNB in terms of appropriate use, diagnostic yield, complications, and whether or not specimens should be handled by cytopathologists, surgical pathologists, or both remain subjects of controversy. This review addresses the issues of sample adequacy, appropriate use of each technique and complications, and challenges regarding the diagnosis of both hepatic tumors and non-neoplastic liver disease.

Fibronodular hepatocellular carcinoma-a new variant of liver cancer: clinical, pathological and radiological correlation

AIMS

To establish and define a new, not previously reported hepatocellular carcinoma (HCC) variant, termed fibronodular HCC (FN-HCC).

METHODS

We retrospectively reviewed 290 HCC cases and identified 29 FN-HCC and 24 scirrhous HCC (SCHCC). Clinical, pathological and radiological features of FN-HCC were reviewed and compared with 30 conventional HCCs (CV-HCC) and SC-HCC.

RESULTS

FN-HCCs were more likely to arise in non-advanced fibrotic livers with lower advanced Barcelona Clinic Liver Cancer (BCLC) stage, had lower rates of progression and longer time to progression and were more likely to be surgically resected compared with CV-HCCs and SC-HCCs. Imaging analysis of FN-HCCs demonstrated higher rates of non-peripheral washout and a new distinct pattern of enhancement which is characterised by the presence of multiple rounded nodules within a lesion embedded in fibrotic-appearing parenchyma.

CONCLUSIONS

FN-HCC may represent a specific variant of HCC with distinct pathological, radiological and clinical features with potential ramifications for outcome.

Clinical features and surgical outcomes of fibrolamellar hepatocellular carcinoma: retrospective analysis of a single-center experience

Background

Clinicopathological features and surgical outcomes of patients with fibrolamellar hepatocellular carcinoma (FL-HCC) are underreported. The aim of this study is to describe clinical characteristics and surgical outcomes for patients with this rare tumor to raise awareness among clinicians and surgeons.

Methods

Retrospective review of records of a tertiary referral center and specialized liver unit was performed. Out of 3623 patients who underwent liver resection, 366 patients received surgical treatment for HCC; of them, eight (2.2%) had FL-HCC and were resected between October 2001 and December 2018.

Results

Eight patients (3 males and 5 females) with FL-HCC (median age 26 years) underwent primary surgical treatment. All patients presented with unspecific symptoms or were diagnosed as incidental finding. No patient had cirrhosis or other underlying liver diseases. Coincidentally, three patients (37.5%) had a thromboembolic event prior to admission. The majority of patients had BCLC stage C and UICC stage IIIB/IVA; four patients (50%) presented with lymph node metastases. The median follow-up period was 33.5 months. The 1-year survival was 71.4%, and 3-year survival was 57.1%. Median survival was at 36.4 months. Five patients (62.5%) developed recurrent disease after a median disease-free survival of 9 months. Two patients (25.0%) received re-resection.

Conclusion

FL-HCC is a rare differential diagnosis of liver masses in young patients. Since the prognosis is limited, patients with incidental liver tumors or lesions with suspicious features in an otherwise healthy liver should be presented at a specialized hepatobiliary unit. Thromboembolism might be an early paraneoplastic symptom and needs to be elucidated further in the context of FL-HCC.

Outcomes of Patients with Scirrhous Hepatocellular Carcinoma: Insights from the National Cancer Database

INTRODUCTION

Scirrhous hepatocellular carcinoma (HCC) is a rare primary liver tumor characterized by extensive fibrosis and production of parathyroid hormone-related peptide. There have been conflicting reports on patient survival in scirrhous versus non-scirrhous HCC. The objective of the present study was to define the clinical features, practice patterns, and long-term outcomes of patients with scirrhous HCC versus non-scirrhous HCC in a propensity score-matched cohort.

METHODS

A propensity score-matched cohort was created using data from the National Cancer Database for 2004 to 2015. A multivariable Cox proportional hazards regression analysis was performed to assess the effect of the scirrhous HCC variant on overall survival.

RESULTS

Among the 70,426 patients with a diagnosis of HCC who met the inclusion criteria, 99.8% had non-scirrhous HCC (n = 70,290) whereas a small subset had scirrhous HCC (n = 136, 0.19%). While 20,330 (28.9%) patients underwent liver-directed therapy (resection, ablation, and transplantation), the majority did not (n = 50,096, 71.1%). After propensity matching, there were no difference in 1-, 3-, or 5-year overall survival among patients with scirrhous versus non-scirrhous HCC (1-year overall survival (OS), 53.7% versus 51.0%; 3-year OS, 34.6% versus 28.7%; and 5-year OS, 18.0% versus 21.0%, respectively; p = 0.52). While the scirrhous HCC variant was not associated with survival (hazard ratio [HR] 0.93, 95% CI 0.74-1.16), non-receipt of liver-directed therapy (HR 0.24, 95% CI 0.18-0.32), advanced AJCC stage (III/IV) (HR 2.14, 95% CI 1.55-2.95), and non-academic facilities (HR 0.60, 95% CI 0.49-0.73) remained associated with worse survival.

CONCLUSION

Patients with the scirrhous variant had a comparable overall survival compared with individuals who had non-scirrhous HCC. Failure to receive liver-directed therapy, advanced AJCC stage (III/IV), and treatment at a non-academic facility was strongly associated with a worse long-term prognosis.

Infiltrative non-mass-like hepatocellular carcinoma initially presenting with isolated malignant portal vein thrombosis: A case report and review of the literature

Hepatocellular carcinoma (HCC) shows a rising incidence and mortality rates worldwide. HCC is divided into several distinct subtypes, both morphologically and histopathologically. Among these subtypes, infiltrative HCC may be the most challenging subtype to diagnose, given its characteristic myriad of tumor nodules blended with normal hepatocytes without a distinct mass-like lesion. Herein, we report an unusual case of an infiltrative HCC initially presenting with isolated malignant portal vein thrombosis and provide a brief review of the literature regarding the infiltrative HCC subtype. Additionally, we demonstrate how sonoelastography could aid in detecting the appropriate biopsy area in the infiltrative HCC subtype. To our knowledge, there have not been previously reported cases describing the use of sonoelastography in the evaluation of the appropriate area for the targeted liver biopsy.

Diagnostic efficacy of dynamic liver imaging using qualitative diagnostic algorithm versus LI-RADS v2018 lexicon for atypical versus classical HCC lesions: A decade of experience from a tertiary liver institute

OBJECTIVE

To analyze and evaluate the diagnostic performance of conventional diagnostic (qualitative) imaging features versus LI-RADSv2018 lexicon for indeterminate and atypical Hepatocellular carcinoma (HCC) on dynamic liver imaging with reference to histopathology.

PATIENTS AND METHODS

This retrospective study (June 2009-June 2019) evaluated the performance characteristics of conventional imaging findings, versus the Liver Imaging Reporting and Data System (LIRADS) v2018, for interpretation of indeterminate and atypical HCC, in patients who underwent subsequent histopathological analysis (gold standard). A total of 100,457 dynamic hepatobiliary CT and MR examinations were performed over ten years at our institute. Using current international imaging guidelines, 3218 patients were found to have suspected liver cancer lesions on imaging. Classical enhancement pattern of typical HCC was seen in 2916 of these patients. These patients did not require further biopsy. We enrolled, the remaining (n = 302) patients, who underwent biopsy, into our study group. Two radiologists, blinded to pathology findings, reviewed and classified these lesions, in consensus, according to LI-RADS® lexicon and as per 'conventional' (Indeterminate, Atypical HCC, Classical HCC, other malignancies) imaging. The histopathology diagnosis was considered as the final diagnosis. Alpha feto protein (AFP) levels amongst various subgroups were compared. Statistical analysis was performed to calculate the efficacy of LIRADS versus qualitative imaging parameters in comparison with histopathology.

RESULTS

A total of n = 302 patients, [89 % men (n = 269), mean age 57.08 ± 12.43 years] underwent biopsy for suspected liver lesions. Qualitative imaging had 92.3 % (CI 88.53-94.91) sensitivity, 41.4 % (CI 25.51-59.26) specificity, positive predictive value (PPV) of 93.7 % (CI 90.11-96.02), negative predictive value (NPV) of 36.4 % (CI 22.19-53.38), positive likelihood ratio (PLHR) of 1.575 (CI 1.40-1.77) and negative likelihood ratio of (NLHR) 0.19 (CI 0.13-0.26). It correctly classified 87.4 % of lesions diagnosed on pathology. In comparison, LI-RADS was found to have 92 % sensitivity, 55.5 % specificity, 97 % PPV, 30.3 %, NPV, PLHR 2.068 (CI 1.62-2.64), NLHR 0.15 (CI 0.11-0.18) and 89.7 % diagnostic accuracy. A total of 38 patients (17 false negative, 21 false positive lesions) had discordant diagnoses on imaging versus histopathology. The kappa agreement between LIRADs and qualitative Imaging was found to be 0.77 ± .07 (p < 0.001). LIRADS and qualitative imaging collectively had 97 % sensitivity, 30 % specificity, 91.9 % PPV, 55.6 % NPV, PLHR of 1.39 (CI 1.27-1.51) and NLHR of 0.09 (0.048-0.19) which was better than, either reporting system, independently.

CONCLUSION

It was observed that the LI-RADS v2018 lexicon with qualitative imaging as a combination technique added extra value in interpretation of atypical HCC or indeterminate lesions on dynamic CT and MRI compared to either as 'stand- alone' reporting systems.

Management and outcomes among patients with sarcomatoid hepatocellular carcinoma: A population-based analysis

BACKGROUND

Few data are available regarding the management and outcomes among patients with sarcomatoid hepatocellular carcinoma (HCC) due to its rarity.

METHODS

Patients diagnosed with sarcomatoid HCC from 2004 through 2015 were identified in the National Cancer Data Base. Overall survival (OS) was calculated among patients with sarcomatoid versus conventional HCC using a 1:3 propensity score matching based on sex, age, and American Joint Committee on Cancer (AJCC) stage of disease.

RESULTS

The final analytic cohort included 104 patients with sarcomatoid HCC and 312 patients with conventional HCC. Patients with sarcomatoid HCC more often had a larger median tumor size (8.5 cm vs 5.4 cm; P < .001) and poorly or undifferentiated tumors (52.9% vs 13.8%; P < .001) compared with patients who had conventional HCC. 5-year OS was worse among patients with sarcomatoid versus conventional HCC (5.7% vs 30.1%; P < .001). Subgroup analysis demonstrated worse 5-year OS among patients with sarcomatoid versus conventional HCC among patients treated with either curative-intent or palliative therapies. Stage-specific subgroup analysis indicated a worse OS among patients with AJCC stage I, stage II, or stage III sarcomatoid HCC. On multivariable analysis, uninsured status, advanced AJCC stage (stage III/stage IV), and histological sarcomatoid subtype were independently associated with worse outcomes (all P < .05).

CONCLUSIONS

Sarcomatoid HCC is a very rare variant of HCC, which was associated with larger tumor size and worse tumor grade on presentation. On propensity score matched analyses that controlled for known confounding factors, patients with sarcomatoid HCC had a worse stage-for-stage long-term survival compared with patients who had conventional HCC.

Update on hepatocellular carcinoma: Pathologists’ review

Histopathologic diversity and several distinct histologic subtypes of hepatocellular carcinoma (HCC) are well-recognized. Recent advances in molecular pathology and growing knowledge about the biology associated with distinct histologic features and immuno-profile in HCC allowed pathologists to update classifications. Improving sub-classification will allow for more clinically relevant diagnoses and may allow for stratification into biologically meaningful subgroups. Therefore, immuno-histochemical and molecular testing are not only diagnostically useful, but also are being incorporated as crucial components in predicting prognosis of the patients with HCC. Possibilities of targeted therapy are being explored in HCC, and it will be important for pathologists to provide any data that may be valuable from a theranostic perspective. Herein, we review and provide updates regarding the pathologic sub-classification of HCC. Pathologic diagnostic approach and the role of biomarkers as prognosticators are reviewed. Further, the histopathology of four particular subtypes of HCC: Steatohepatitic, clear cell, fibrolamellar and scirrhous - and their clinical relevance, and the recent consensus on combined HCC-cholangiocarcinoma is summarized. Finally, emerging novel biomarkers and new approaches to HCC stratification are reviewed.

The Carcinogenic Role of the Notch Signaling Pathway in the Development of Hepatocellular Carcinoma

The Notch signaling pathway, known to be a highly conserved signaling pathway in embryonic development and adult tissue homeostasis, participates in cell fate decisions that include cellular differentiation, cell survival and cell death. However, other studies have shown that aberrant in Notch signaling is pro-tumorigenic, particularly in hepatocellular carcinoma (HCC). HCC is one of the most common malignant tumors in the world and has a high mortality rate. Growing evidence supports that Notch signaling plays a critical role in the development of HCC by regulating the tumor microenvironment, tumorigenesis, progression, angiogenesis, invasion and metastasis. Accordingly, overexpression of Notch is closely associated with poor prognosis in HCC. In this review, we focus on the pro-tumorigenic role of Notch signaling in HCC, summarize the current knowledge of Notch signaling and its role in HCC development, and outline the therapeutic potential of targeting Notch signaling in HCC.

A phenotypical map of disseminated hepatocellular carcinoma suggests clonal constraints in metastatic sites

AIMS

Access to tissue in patients with hepatocellular carcinoma (HCC) is limited compared to other malignancies, particularly at advanced stages. This has precluded a thorough characterisation of molecular drivers of HCC dissemination, particularly in relation to distant metastases. Biomarker assessment is restricted to early stages, and paired primary-metastatic comparisons between samples from the same patient are difficult.

METHODS AND RESULTS

We report the evaluation of 88 patients with HCC who underwent autopsy, including multiregional sampling of primary and metastatic sites totalling 230 nodules analysed. The study included morphological assessment, immunohistochemistry and mutation status of the TERT promoter, the most frequently mutated gene in HCC. We confirm a strong predilection of HCC for lung dissemination, including subclinical micrometastases (unrecognised during imaging and macroscopic examinations) in 30% of patients with disseminated disease. Size of dominant tumour nodule; multinodularity; macrovascular invasion; high histological, nuclear and architectural grades; and cellular crowding were associated with the presence of extrahepatic metastasis. Among the immunohistochemistry markers tested, metastatic nodules had significantly higher K19 and EpCAM expression than primary liver tumours. Morphological and immunohistochemical features showed that metastatic HCC could be traced back to the primary tumour, sometimes to a specific hepatic nodule.

CONCLUSIONS

This study suggests limited heterogeneity in metastatic sites compared to primary tumour sites.

Molecular Diagnostics in the Neoplasms of the Pancreas, Liver, Gallbladder, and Extrahepatic Biliary Tract: 2018 Update

Pancreatic neoplasms, including ductal adenocarcinoma, solid pseudopapillary neoplasm, pancreatic endocrine neoplasms, acinar cell carcinoma, and pancreatoblastoma, are associated with different genetic abnormalities. Hepatic adenomas with beta-catenin exon 3 mutation are associated with a high risk of malignancy. Hepatic adenoma with arginosuccinate synthetase 1 expression or sonic hedgehog mutations are associated with a risk of bleeding. Hepatocellular carcinoma and choangiocarcinoma display heterogeneity at both morphologic and molecular levels Cholangiocellular carcinoma is most commonly associated with IDH 1/2 mutations.

Management of combined hepatocellular carcinoma-cholangiocarcinoma

PURPOSE OF REVIEW

To review the recent consensus on the nomenclature, clinical features, diagnosis, and treatment of combined hepatocellular carcinoma-cholangiocarcinoma (cHCC-CCA).

RECENT FINDING

cHCC-CCA is a primary liver carcinoma with varying degrees of hepatocytic and cholangiocytic cytology and architecture within the same tumor. The diagnosis of cHCC-CCA can only be established based on histologic examination. Surgical resection should be considered in patients with resectable tumors who do not have underlying liver disease or clinically significant portal hypertension. While treatment by liver transplantation (LT) is controversial due to the high risk of post LT recurrence, LT should remain as a potentially curative option in a highly selected group of patients. Little data exist for the outcome of other treatments.

SUMMARY

High quality multicenter prospective studies should be conducted to better understand this rare, but increasingly recognized tumor.

Update on the pathology of liver neoplasms

Many advances have developed in the pathology of liver tumors in the recent decade. Examples of these advances include the use of glutamine synthetase in the diagnosis of focal nodular hyperplasia, subtyping of hepatocellular adenomas using molecular and immunohistochemical methods, the unraveling of the fusion transcript between the DNAJB1 gene and the PRKACA gene in fibrolamellar carcinoma, and the more unified classification and terminology in intrahepatic bile duct tumors and their precursor lesions. Nevertheless, challenges still remain, e.g., the differential diagnosis between well-differentiated hepatocellular carcinoma and hepatocellular adenoma; distinction among poorly differentiated hepatocellular carcinoma, cholangiocarcinoma and metastatic neoplasm; terminology of the combined hepatocellular carcinoma-cholangiocarcinoma, etc. This review aims to address updates in the pathologic diagnosis and clinical relevance of tumors of the liver and intrahepatic bile ducts in adults and their differential diagnosis and diagnostic pitfalls.

Changing role of histopathology in the diagnosis and management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common and fatal cancer in the world. HCC frequently presents with advanced disease, has a high recurrence rate and limited treatment options, which leads to very poor prognosis. This warrants urgent improvement in the diagnosis and treatment. Liver biopsy plays very important role in the diagnosis and prognosis of HCC, but with technical advancements and progression in the field of imaging, clinical guidelines have restricted the role of biopsy to very limited situations. Biopsy also has its own problems of needle tract seeding of tumor, small risk of complications, technical and sampling errors along with interpretative errors. Despite this, tissue analysis is often required because imaging is not always specific, limited expertise and lack of advanced imaging in many centers and limitations of imaging in the diagnosis of small, mixed and other variant forms of HCC. In addition, biopsy confirmation is often required for clinical trials of new drugs and targeted therapies. Tissue biomarkers along with certain morphological features, phenotypes and immune-phenotypes that serve as important prognostic and outcome predictors and as decisive factors for therapy decisions, add to the continuing role of histopathology. Advancements in cancer biology and development of molecular classification of HCC with clinic pathological correlation, lead to discovery of HCC phenotypic surrogates of prognostic and therapeutically significant molecular signatures. Thus tissue characteristics and morphology based correlates of molecular subtypes provide invaluable information for management and prognosis. This review thus focuses on the importance of histopathology and resurgence of role of biopsy in the diagnosis, management and prognostication of HCC.

Dichotomous associations of liver pathology with hepatocellular carcinoma morphology in Middle Africa: the situation in Cameroon

Objective

This study evaluates the occurrence of the various morphological subtypes of hepatocellular carcinoma (HCC) and their connections with some risk factors in Cameroonian patients. The database of the 360 liver biopsies received and associated medical records were reviewed for histological and demographic analysis. Archival formalin-fixed and paraffin embedded liver biopsy specimens or slide were re-evaluated in malignancies patients. HCC classification was determined according to the World Health Organization criteria.

Results

Malignancies were confirmed in 24.7% (89/360) of liver biopsies. Primary liver tumors consisted in 80 cases of HCC and one case of hepatoblastoma. The distribution of the morphological variants of HCC was trabecular pattern (n = 45/80, 56.25%), acinar/pseudoglandular (32.5%) or scirrhous (11.2%). Remarkably, liver steatosis was present in 60.0% (48/80) of patients with HCC, most of them infected with hepatitis C virus (75.8%). Well-differentiated trabecular tumors were significantly associated with important fibrotic and necro-inflammatory activities in livers (P = 0.008) whereas acinar pattern was more frequent on fatty livers (P = 0.02). Our finding indicates that in Middle Africa the morphology of HCC subtypes correlates with changes affecting non-tumor liver tissue. Trabecular subtype is installed by strong liver injury whereas acinar pattern is more often associated with lipid metabolism defects.

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3560-x) contains supplementary material, which is available to authorized users.

Role of interventional radiology in managing pediatric liver tumors : Part 1: Endovascular interventions

Primary liver malignancies are rare in children. Hepatoblastoma and hepatocellular carcinoma (HCC) together represent the overwhelming majority of cases. Overall survival of hepatoblastoma approaches 80% with multimodal treatment approaches that include chemotherapy, surgery and transplantation. However, there remains a subset of children with hepatoblastoma in whom resection or transplantation is not possible. The 5-year survival for children diagnosed with HCC is less than 30% and remains a significant therapeutic challenge. The poor outcomes for children with primary liver tumors motivate investigation of new therapeutic alternatives. Interventional oncology offers a broad scope of percutaneous and transcatheter endovascular cancer therapies that might provide clinical benefits. Minimally invasive approaches are distinct from medical, surgical and radiation oncologic treatments, and in adults these approaches have been established as the fourth pillar of cancer care. Transarterial chemoembolization is a minimally invasive locoregional treatment option performed by interventional radiologists with level-I evidence as standard of care in adults with advanced liver malignancy; transarterial chemoembolization in adults has served to prolong disease-free progression, downstage and bridge patients for surgical and transplant interventions, and improve overall survival. However, while several groups have reported that transarterial chemoembolization is feasible in children, the published experience is limited primarily to small retrospective case series. The lack of prospective trial evidence has in part limited the utilization of transarterial chemoembolization in the pediatric patient population. The purpose of this article is to provide an overview of the role of interventional radiology in the diagnosis and endovascular management of hepatic malignancies in children.