Fibrolamellar hepatocellular carcinoma

Fibrolamellar hepatocellular carcinoma: a case report and gene analysis

BACKGROUND

Fibrolamellar hepatocellular carcinoma (HCC) (FL-HCC) is rare in Japan. FL-HCC develops in young patients with no history of cirrhosis and tends to manifest lymphatic metastasis with clinical features similar to those of HCC. We present a case of FL-HCC in a young male patient.

CASE PRESENTATION

A 14-year-old male patient underwent abdominal computed tomography (CT) to diagnose appendicitis, wherein a hepatic tumor was detected. Dynamic enhanced CT revealed a 35-mm solid tumor, which contrasted at the early phase of dynamic enhanced study of the right hepatic segments, with occlusion of the right portal vein. We performed right hepatectomy for these lesions. The patient experienced a single lymphatic recurrence on the hepatoduodenal ligament 12 months after the initial surgery. We performed lymphadenectomy for the recurrent tumor. We performed RNA sequencing (RNA-seq) and targeted DNA sequencing of the resected specimens (primary tumor, lymphatic metastasis, and normal liver). RNA-seq detected DNAJB1-PRKACA in both primary and metastatic lesions as previously reported. Furthermore, The Cancer Genome Atlas (TCGA) database was used to compare other gene expressions in this case with those of previously reported cases of FL-HCC and HCC in young patients. Principal component analysis of differentially expressed genes in the top 10% revealed that the gene expression in our case was similar to that of previous FL-HCC cases but was a different cluster from that in HCC cases in young patients. Mutational analysis did not detect any somatic mutations associated with carcinogenesis, including previously reported mutations (Kastenhuber et al. in Proc Natl Acad Sci USA 114: 13076-84, 2017).

CONCLUSION

We encountered a case of FL-HCC, a rare hepatic tumor in an adolescent patient, and evaluated the genetic background. Our findings could contribute to the elucidation of the mechanisms underlying carcinogenesis and progression in patients with FL-HCC and thereby contribute to the development of new therapeutic strategies in the future that may improve patient prognosis.

Exploring the molecular pathogenesis, diagnosis and treatment of fibrolamellar hepatocellular carcinoma: A state of art review of the current literature

This paper aims to present a detailed overview of fibrolamellar carcinoma (FLC), a variant of hepatocellular carcinoma (HCC) that accounts for approximately 1-9% of all cases a. according to the SEER database. Despite ongoing research, the aetiology of FLC tumours remains unclear. Nevertheless, FLC is believed to have a better overall prognosis than other primary liver tumours, such as hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma. This study aims to present a comprehensive overview of fibrolamellar carcinoma (FLC), with a focus on its epidemiology, pathogenesis, diagnosis, treatment, and prognosis. FLC frequently incorporate features of stomach pain, weight loss, and malaise in their clinical signs and symptoms, which are generally nonspecific Ultimately, the most common physical finding is an abdominal mass or hepatomegaly. With this said, several unusual presentations have been documented such as Budd Chiari syndrome, severe anaemia, non-bacterial thrombotic endocarditis and many more. In regards to this tumour's genetic analysis, it is characterised by a 400 kb deletion on chromosome 19 leading to a functional DNAJB1-PRKACA chimeric transcript in addition to tetraploidy in 50% of cases. FLC is chromosomally stable as compared to typical HCC. mTOR pathway activation has also been found to play a critical role in 47% of these tumours and EFGR over-expression is also evident. Fibrolamellar carcinomas (FLCs) exhibit a distinctive gross appearance, characterized by a yellow to pale tan colour, with a consistency that can vary from soft to firm and hard. In addition, a central scar is observed in 60-70% of FLC cases. The central scar is typically white or grey in colour and has a fibrous appearance, which is often surrounded by nodular, tumour-like tissue. Its histologic appearance is characterized by large polygonal cells with abundant eosinophilic cytoplasm, large vesiculated nuclei, large nucleoli, and arranged in lamellar bands of collagen fibres. Lamellar bands of fibrosis, consisting of collagen type I, III and IV, have also been identified as a distinctive histologic feature that is observed under low power magnification. Ultrasound, CT and MRI along with image guided biopsy are the primary modalities in diagnosis. Current management options include systemic therapy which has thus far been unremarkable with platinum-based therapies as well combination therapy with interferon alpha-2b being the most successful options. Surgical resection remains the primary treatment modality and there have been no advances in targeted therapies. Although the prognosis for FLC is favourable as compared to other hepatic cancer subtypes such as intrahepatic cholangiocarcinoma, there is a high rate of recurrence ranging from 33% to 100% with a median recurrence-free survival of 20-48 months. As a result of this there is a low overall cure rate associated with this tumour type and much more research is required to gain an in-depth understanding of the molecular mechanisms occurring in order to provide more adequate treatment to patients who suffer from this condition.

Multicentric Fibrolamellar Hepatocellular Carcinoma: A Rare Case Report

Multicentric fibrolamellar hepatocellular carcinoma has not been reported yet in the world as of our knowledge. A Medline search for the term “multicentric fibrolamellar HCC” did not return any results. To our knowledge, this is the first case report of multi-centric fibrolamellar hepatocellular carcinoma (HCC). We present the case of a 22-year-old male patient who had complaints of epigastric pain for 1 month. His general physical examinations were normal. Computed tomography of the abdomen revealed multiple hyper-enhancing space-occupying lesions, one of which showed a central scar. The final diagnosis of the case was multicentric fibrolamellar HCC, which was biopsy proven.

MRI features of histologic subtypes of hepatocellular carcinoma: correlation with histologic, genetic, and molecular biologic classification

HCC is a heterogeneous group of tumors in terms of histology, genetic aberration, and protein expression. Advancements in imaging techniques have allowed imaging diagnosis to become a critical part of managing HCC in the clinical setting, even without pathologic diagnosis. With the identification of many HCC subtypes, there is increasing correlative evidence between imaging phenotypes and histologic, molecular, and genetic characteristics of various HCC subtypes. In this review, current knowledge of histologic heterogeneity of HCC correlated to features on gadolinium-enhanced dynamic liver MRI will be discussed. In addition, HCC subtype classification according to transcriptomic profiles will be outlined with descriptions of histologic, genetic, and molecular characteristics of some relatively well-established morphologic subtypes, namely the low proliferation class (steatohepatitic HCC and CTNNB1-mutated HCC) and the high proliferation class (macrotrabecular-massive HCC (MTM-HCC), scirrhous HCC, and CK19-positive HCC). Characteristics of sarcomatoid HCC and fibrolamellar HCC will also be discussed. Further research on radiological characteristics of HCC subtypes may ultimately enable non-invasive diagnosis and serve as a biomarker in predicting prognosis, molecular characteristics, and therapeutic response. In the era of precision medicine, a multidisciplinary effort to develop an integrated radiologic and clinical diagnostic system of various HCC subtypes is necessary. KEY POINTS: • HCC is a heterogeneous group of tumors in terms of histology, genetic aberration, and protein expression, which can be divided into many subtypes according to transcriptome profiles. • There is increasing evidence of a correlation between imaging phenotypes and histologic, genetic, and molecular biologic characteristics of various HCC subtypes. • Imaging characteristics may ultimately enable non-invasive diagnosis and subtype characterization, serving as a biomarker for predicting prognosis, molecular characteristics, and therapeutic response.

Fibrolamellar hepatocellular carcinoma: A rare but unpleasant event

Fibrolamellar carcinoma (FLC) is a rare variant of hepatocellular carcinoma (HCC), comprising 1%–9% of all HCCs. FLC is a poorly understood malignancy, which seems to be more prevalent in young patients with no underlying liver diseases. The term “fibrolamellar” is derived from thick fibrous collagen bands surrounding the tumor cells. Unlike HCC, cirrhosis and viral hepatitis infection are not predisposing to FLC, and it is not associated with elevations in serum alpha-fetoprotein. FLC patients often present with vague abdominal pain, nausea, malaise, and weight loss. Most cases present are at an advanced stage at the time of initial diagnosis. However, curative treatment options can still be offered to up to 70% of patients. Surgery (resection/liver transplantation) is the mainstay of treatment and the only potentially curative option. FLCs have been less chemo-responsive than the conventional HCC, however, in advanced cases, multimodality treatments can be effective. Recent advances in molecular studies of FLC have found a unique DNAJB1–PRKACA fusion transcript in most of the cases studied. The review aims to describe clinical characteristics, diagnostic methods, and therapeutic modalities for this rare tumor to raise awareness among clinicians and surgeons.

Risk Factors for Hepatocellular Carcinoma: A Historical Perspective

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Pediatric Liver Tumors: Updates in Classification

Malignant primary liver tumors are rare in children. Yet a wide histologic spectrum is seen, particularly in hepatoblastoma, the most common malignant liver tumor in children. Furthermore, there can be significant morphologic overlap with hepatocellular carcinoma, the second most common pediatric liver malignancy, and tumors with hybrid features of hepatoblastoma and hepatocellular carcinoma are also reported (currently placed in the provisional category of malignant hepatocellular neoplasm, not otherwise specified). This review provides detailed morphologic descriptions and updates in the evolving clinical context of these tumors, and presents recent molecular advances that may further help in accurate classification of these tumors, which is critical in their management.

New insights into the pathophysiology and clinical care of rare primary liver cancers

Hepatocholangiocarcinoma, fibrolamellar carcinoma, hepatic haemangioendothelioma and hepatic angiosarcoma represent less than 5% of primary liver cancers. Fibrolamellar carcinoma and hepatic haemangioendothelioma are driven by unique somatic genetic alterations (DNAJB1-PRKCA and CAMTA1-WWTR1 fusions, respectively), while the pathogenesis of hepatocholangiocarcinoma remains more complex, as suggested by its histological diversity. Histology is the gold standard for diagnosis, which remains challenging even in an expert centre because of the low incidences of these liver cancers. Resection, when feasible, is the cornerstone of treatment, together with liver transplantation for hepatic haemangioendothelioma. The role of locoregional therapies and systemic treatments remains poorly studied. In this review, we aim to describe the recent advances in terms of diagnosis and clinical management of these rare primary liver cancers.

Atypical Appearance of Hepatocellular Carcinoma and Its Mimickers: How to Solve Challenging Cases Using Gadoxetic Acid-Enhanced Liver Magnetic Resonance Imaging

Hepatocellular carcinoma (HCC) can be diagnosed noninvasively with contrast-enhanced dynamic computed tomography, magnetic resonance imaging, or ultrasonography on the basis of its hallmark imaging features of arterial phase hyperenhancement and washout on portal or delayed phase images. However, approximately 40% of HCCs show atypical imaging features, posing a significant diagnostic challenge for radiologists. Another challenge for radiologists in clinical practice is the presentation of many HCC mimickers such as intrahepatic cholangiocarcinoma, combined HCC-cholangiocarcinoma, arterioportal shunt, and hemangioma in the cirrhotic liver. The differentiation of HCCs from these mimickers on preoperative imaging studies is of critical importance. Hence, we will review the typical and atypical imaging features of HCCs and the imaging features of its common mimickers. In addition, we will discuss how to solve these challenges in practice.

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.

Fibrolamellar hepatocellular carcinoma: multiphasic CT features of the primary tumor on pre-therapy CT and pattern of distant metastases

OBJECTIVE

The aim of our study is to describe the multiphasic CT features of fibrolamellar hepatocellular carcinomas (FLHCCs) and pattern of distant metastases.

MATERIALS AND METHODS

33 patients (mean age 28 years: 17M/16F) with pathologically confirmed FLHCC and pre-treatment multiphasic CT were included in the study. Two abdominal radiologists evaluated the multiphasic CT imaging features of these 33 FLHCC patients in consensus.

RESULTS

Solitary hepatic mass was seen in 67% (22/33). Mean tumor size was 11.3 cm (range 4.6-22 cm). Tumor was well-defined in 64% (21/33). In the pre-contrast CT, 91% (30/33) were hypoattenuating. Central stellate scar was present in 73% (24/33). In FLHCC having central stellate scar, calcification within the central scar was seen in 88% (21/24). In the hepatic arterial phase, 82% (27/33) were hyperattenuating relative to liver. In the portal venous phase, 36% (12/33) were hyperattenuating, 46% (15/33) were isoattenuating, and 18% (6/33) were hypoattenuating. In the delayed phase images, 24% (8/23) were hyperattenuating, 67% (22/33) were isoattenuating, and 9% (3/33) were hypoattenuating. Delayed enhancement of the central stellate scar was seen in 12% (4/33). Distant metastases were seen in 54% (18/33). The most common site of metastases was lungs and was seen in 89% (16/18) of the patients with metastatic disease.

CONCLUSION

FLHCC typically manifests as a large, solitary mass demonstrating heterogeneous hypervascular enhancement in the arterial phase. Most tend to be isoattenuating in delayed phase. Central stellate scar with internal calcification is a useful imaging feature that can help in the diagnosis of FLHCC. Lungs are the most common site of distant metastases in FLHCC.

Contemporary management of fibrolamellar hepatocellular carcinoma: diagnosis, treatment, outcome, prognostic factors, and recent developments

Fibrolamellar hepatocellular carcinoma (FL-HCC) is a malignant liver tumor which is thought to be a variant of conventional hepatocellular carcinoma (HCC). It accounts for a small proportion of HCC cases and occurs in a distinctly different group of patients which are young and usually not in the setting of chronic liver disease. The diagnosis of FL-HCC requires the integration of clinical information, imaging studies, and histology. In terms of the treatment options, the only potentially curative treatment option for patients who have resectable disease is surgery either liver resection (LR) or liver transplantation (LT). When performed in a context of aggressive therapy, long-term outcomes after surgery, particularly liver resection for FL-HCC, were favorable. The clinical outcome of patients with unresectable disease is suboptimal with median survival of less than 12 months. The aim of this review is to update the available evidence on diagnosis, treatment options, outcome predictors, and recent developments of patients with this rare disease and to provide a summarized overview of the available literature.

Fibrolamellar hepatocellular carcinoma: current clinical perspectives

Fibrolamellar carcinoma (FLC) is a variant of hepatocellular carcinoma (HCC), which comprises ∼1%–9% of all HCCs. Although FLC is a variant of HCC, it is distinct from HCC in that it most often affects younger patients (10–35 years of age) with no underlying liver disease. FLC often presents with vague abdominal pain, nausea, abdominal fullness, malaise, and weight loss. Surgery is the current mainstay of treatment for FLC and remains the only potentially curative option. While FLCs are considered less responsive to chemotherapy than their classic HCC counterparts, there have been suggestions that multimodality treatments may be effective, especially in advanced cases. Further research is necessary to determine effective systemic therapies as an adjunct to surgery for FLC.

CT and MRI of primary and metastatic fibrolamellar carcinoma: a case series of 37 patients

OBJECTIVE

Fibrolamellar carcinoma (FLC) is a rare disease, with limited radiographic reported information. We assessed the imaging patterns of primary and metastatic FLC.

METHODS

CT and MR examinations of patients with FLC were retrospectively reviewed. Imaging features were assessed for primary and recurrent liver tumours, including dimension, enhancement characteristics, and presence or absence of central scars. Locations of nodal and extranodal metastases were also recorded.

RESULTS

Of 37 patients (18 males and 19 females; average age, 23.5 years) with FLC, 24 had imaging of their primary tumour; 13 had metastases at presentation and 7 developed metastases on follow-up. The remaining 13 patients had follow-up imaging of metastatic disease. Primary FLC had a mean diameter >11 cm, with central scars in ten (46%) patients. Most tumours enhanced heterogeneously (96%) and showed arterial enhancement (81%). On MRI, 62% of FLCs were hypointense on T1 weighted imaging and 54% were hyperintense on T2 weighted imaging. 13 patients (54%) had nodal metastases at presentation, mostly in the upper abdomen (92%) and commonly in the chest (38%). Extrahepatic metastases were most frequently pulmonary or peritoneal. Predominantly small and homogeneous intrahepatic recurrences were detected on follow-up in 15 patients.

CONCLUSION

FLC often presents as a large hepatic tumour with nodal and distant metastases. Thoracic adenopathy and lung metastases were frequently found in our series, suggesting the need for pre-operative and follow-up chest imaging.

ADVANCES IN KNOWLEDGE

Thoracic nodal and lung metastases are common in FLC; therefore, dedicated chest imaging should be part of the evaluation of a patient with FLC.

Imaging features of fibrolamellar hepatocellular carcinoma

OBJECTIVE

Fibrolamellar hepatocellular carcinoma (HCC) is a rare primary liver tumor, which significantly differs from conventional HCC. This article reviews the molecular cytogenetics, pathology, imaging features, and management of this relatively rare tumor.

CONCLUSION

Fibrolamellar HCC predominantly occurs in young patients without underlying hepatitis or cirrhosis. Serum α-fetoproteins are not elevated in most cases, and hence imaging plays an important role in diagnosis, staging, and surveillance.

Fibrolamellar hepatocellular carcinoma with biliary tumor thrombus: an unreported association

Fibrolamellar hepatocellular carcinoma (FHCC) is a rare malignant tumor of hepatocyte origin occurring earlier in life than typical hepatocellular carcinoma (HCC). We describe a distinctive case of FHCC with biliary tumor thrombus (BTT) in a 25-year-old Caucasian patient, pointing out the imaging features supported by histopathology.

A systematic review: treatment and prognosis of patients with fibrolamellar hepatocellular carcinoma

BACKGROUND

Fibrolamellar hepatocellular carcinoma (FLC) is a rare primary liver tumor presenting earlier in life than nonfibrolamellar hepatocellular carcinoma (NFL-HCC), with distinct epidemiologic and clinical characteristics. Although FLC is believed to have a better prognosis than NFL-HCC, data on treatment and prognosis are scarce. We performed a systematic review to investigate treatment options and clinical outcomes of patients with FLC.

STUDY DESIGN

The study is a systematic review of the literature and pooled analysis of individual patient data.

RESULTS

A total of 35 series were analyzed, reporting on 575 patients (52% female, elevated alpha-fetoprotein in 10%, cirrhosis in 3%, hepatitis B in 2%), most of whom were treated with partial hepatectomy (55%) or orthotopic liver transplantation (23%). Nineteen studies provided data on 206 individual patients with a median age of 21 years and tumor size of 12 cm. Median overall survival (OS) was 39 months; 1-year, 3-year, and 5-year OS rates were 85%, 53%, and 44%, respectively. For patients treated with liver resection, median OS was 18.5 years and 1-year, 3-year, and 5-year OS were 93%, 80%, and 70%, respectively. Based on data from 15 studies, FLC appeared to follow a relatively indolent course compared with NFL-HCC.

CONCLUSIONS

Patients with FLC treated with partial hepatectomy have excellent long-term survival, with 5-year overall survival reaching 70%. Patients fared worse with the use of other therapeutic options including chemotherapy, intra-arterial therapy, and transplantation, although data directly comparing resection vs transplantation were limited.

Focal nodular hyperplasia--a review of myths and truths

BACKGROUND

Focal nodular hyperplasia (FNH) is a benign hyperplastic lesion of the liver with no known malignant potential. It has generated much interest due to the frequency with which it presents with atypical features on radiological imaging. Often resulting in misdiagnosis. Moreover, the understanding of particular subtypes of this lesion at a molecular level has changed in recent years. This may have implications on how certain subtypes should be managed.

PURPOSE

This review aims to analyse current literature pertaining to FNH and to provide clinically relevant advice regarding diagnosis and management.

Radiologists' performance in the diagnosis of liver tumors with central scars by using specific CT criteria

PURPOSE

To determine the performance of radiologists with differing levels of expertise in the diagnosis of the most common types of liver tumors with central scars (ie, focal nodular hyperplasia [FNH], fibrolamellar hepatocellular carcinoma [HCC], and large hepatic hemangioma) by using specific computed tomographic (CT) findings.

MATERIALS AND METHODS

Review of medical records at the University of Pittsburgh Medical Center identified patients with a total of 64 liver tumors that had central scars-including 29 cases of FNH, 20 fibrolamellar HCCs, and 15 large (>3.5 cm in diameter) hemangiomas-and with CT scans available for review. Retrospective review of these scans was performed individually by six radiologists who were blinded to the diagnosis, including two faculty abdominal radiologists, one abdominal imaging fellow, and three radiology residents. Individual performance was evaluated by means of receiver operating characteristic analysis, and interobserver agreement was measured by using the Cronbach alpha. Individual CT findings that may allow differentiation of tumor types were identified with the Kruskal-Wallis test.

RESULTS

CT allowed good to excellent interobserver agreement in the diagnosis of tumor type and in recognition of differential findings among the three types. The individual accuracy of diagnosis was very good, with the average area under the receiver operating characteristic curve ranging from 0.81 to 0.90. Although the faculty radiologists performed the best, the differences in performance between the subgroups of readers and the levels of confidence in diagnosis were not statistically significant. The diagnosis of fibrolamellar HCC was the most accurate and had the highest sensitivity, followed by FNH and large hemangioma. Clinical and CT findings that were found to be statistically significant in differentiating tumor types were patient age and sex, tumor size larger than 10 cm, width of tumor scars, invasion of vessels, nodular centripetal enhancement, marked hyperattenuation on arterial phase images, lymphadenopathy, heterogeneity, extrahepatic metastases, surface lobulation, calcification, and isoattenuation with liver tissue on portal venous phase images.

CONCLUSION

CT allows accurate differentiation of the most common types of liver tumors with central scars, including FNH, fibrolamellar HCC, and large hemangioma.

Malignant liver tumors

The primary hepatic malignancies are a diverse group of neoplasms with distinctive clinical and pathologic features. Imaging of the primary hepatic malignancies continues to be challenging. Ultrasonography, CT scanning, and MR imaging play complementary roles in the evaluation of these patients. Many [figure: see text] of these neoplasms have distinctive imaging features that may permit diagnosis. In most instances, however, biopsy is required for definitive diagnosis and treatment planning.

Hepatocarcinoma fibrolamelar: relato de um caso

O hepatocarcinoma fibrolamelar é neoplasia hepatocelular rara, diagnosticada por tomografia computadorizada e confirmada pelo exame anatomopatológico. O caso relatado foi atendido no Hospital Mater Dei de Belo Horizonte, MG. Os aspectos clínicos, radiológicos e patológicos discutidos reforçam a importância das imagens radiológicas na detecção e caracterização das neoplasias focais hepáticas.

Fibrolamellar hepatocellular carcinoma: pre- and posttherapy evaluation with CT and MR imaging

PURPOSE

To determine the features of advanced hepatic and extrahepatic fibrolamellar hepatocellular carcinomas (HCCs) and their effects on immediate surgical management and tumor recurrence.

MATERIALS AND METHODS

Thirty-one patients with fibrolamellar HCC underwent pretherapy computed tomography (CT); 11 underwent pretherapy magnetic resonance (MR) imaging. All 40 patients underwent posttherapy CT; four, follow-up MR imaging. Imaging, surgical, and histopathologic findings were correlated.

RESULTS

Twenty-five (81%) patients had solitary tumors (mean maximum diameter, 13 cm). Thirteen (42%) patients had intrahepatic biliary obstruction; 27 (87%) patients had involvement of the portal or hepatic veins. Thirteen (42%) had extrahepatic tumor spread, nine (29%) had distant metastases on pretherapy images, and 20 (65%) had lymphadenopathy. Thirty-two (80%) of 40 patients underwent exploration surgery; curative resection was attempted in 25 (62%), including four patients who underwent liver transplantation. Only 17 patients were considered to have had hepatic and extrahepatic tumors completely excised. Tumor recurred in all eight of the 17 patients who had extrahepatic disease at pretherapy CT and in four of the seven patients who seemed to have tumor limited to the liver. A combination of repeat tumor resection and adjuvant chemotherapy resulted in prolonged tumor-free survival in some cases.

CONCLUSION

Fibrolamellar HCC frequently demonstrates aggressive local invasion and nodal and distant metastases. Pretherapy and follow-up imaging are important for staging, surveillance, and optimal management. Aggressive surgical resection may be helpful to control fibrolamellar HCC and to prolong survival in appropriately selected cases.

Fibrolamellar hepatocellular carcinoma: imaging and pathologic findings in 31 recent cases

PURPOSE

To review characteristic findings of fibrolamellar hepatocellular carcinoma (HCC) at computed tomography (CT) and magnetic resonance (MR) imaging.

MATERIALS AND METHODS

The authors retrospectively reviewed the clinical, pathologic, and preoperative imaging findings in 31 patients with histologically proved fibrolamellar HCC. Dynamic contrast material-enhanced CT of the liver was performed in 31 patients, helical multiphase CT in 21, and MR imaging in 11. Complete resection was performed in 17 patients, and imaging-pathologic correlation was performed.

RESULTS

Large tumors (mean diameter, 13 cm) were depicted at CT and MR in all cases. At CT, the margins of the tumors were well defined in 24 (77%) of 31 cases calcifications were depicted in 21 (68%), a central scar in 22 (71%), and abdominal lymphadenopathy in 20 (65%). In 20 (80%) of 25 cases with hepatic arterial phase CT images, all tumors were heterogeneous and depicted areas of hypervascularity. At MR imaging, tumors were hypointense to liver on T1-weighted images (n = 11) and hyperintense to liver on T2-weighted images (n = 10). Calcification was not depicted on MR images, but a central scar was depicted as hypointense to surrounding tumor in nine cases.

CONCLUSION

CT and MR images demonstrate characteristic features that may allow confident diagnosis of fibrolamellar HCC.

Fibrolamellar carcinoma of the liver: radiologic-pathologic correlation

Fibrolamellar carcinoma is a malignant hepatocellular tumor with distinct clinical and pathologic differences from hepatocellular carcinoma. It differs from hepatocellular carcinoma in demographics, condition of the affected liver, tumor markers, and prognosis. Fibrolamellar carcinoma characteristically manifests as a large hepatic mass in adolescents or young adults (without gender predominance). Cirrhosis; elevated alpha-fetoprotein levels; and typical risk factors for hepatocellular carcinoma such as viral hepatitis, alcohol abuse, and metabolic disease are typically absent. Fibrolamellar carcinoma is characterized pathologically by cords of tumor cells surrounded by abundant collagenous fibrous tissue arranged in a parallel or lamellar distribution. Fibrotic lamellae often coalesce to form a central scar. Fibrolamellar carcinoma characteristically appears on radiologic images as a lobulated heterogeneous mass with a central scar in an otherwise normal liver. Radiologic evidence of cirrhosis, vascular invasion, or multifocal disease--findings typical of hepatocellular carcinoma--is uncommon in fibrolamellar carcinoma. Imaging features of fibrolamellar carcinoma overlap with those of other scar-producing lesions including focal nodular hyperplasia (FNH), hepatocellular adenoma and carcinoma, hemangioma, metastases, and cholangiocarcinoma. FNH, in particular, may simulate fibrolamellar carcinoma, since both have similar demographic and clinical characteristics. Because some believe that radiologic diagnosis of FNH is possible, it is important to understand the imaging appearance of fibrolamellar carcinoma to avoid misdiagnosing this malignant tumor as a FNH.

Primary hepatic malignant neoplasms

Although metastatic disease is by far the most common form of neoplastic involvement of the liver, a variety of primary hepatic malignant neoplasms may develop from any of the cell types within the liver. Primary hepatic neoplasms include hepatocellular carcinoma, intrahepatic cholangiocarcinoma, biliary cystadenocarcinoma, and a variety of mesenchymal tumors. This article reviews the clinical presentation and pathology of these tumors and discusses their sonographic, CT scan, and MR imaging appearance.

Hepatic calcification

Although a specific diagnosis of the calcified liver mass may not always be possible, there are some morphologic imaging features that help to indicate the diagnosis (Table 1). The radiologist needs to be aware of the wide spectrum of diseases of the liver that can calcify, and the most common causes. Pathologic correlation with axial imaging has greatly enhanced our understanding and interpretation of the underlying liver lesion, which may help to differentiate benign from malignant etiology.

Magnetic resonance imaging of focal and diffuse hepatic disease

MRI is a powerful tool in the detection and characterization of both focal and diffuse liver pathology. Because of superior soft tissue characterization, direct multi-planar capabilities and lack of ionizing radiation, current state of the art MRI is useful when contrast CT is relatively contraindicated or not definitive. This article reviews the MRI findings of the most common focal and diffuse liver diseases encountered in clinical practice. Reviews of current MR techniques and MR contrast agents used in liver imaging have been recently published. For this article, discussion of specific techniques and use of contrast is addressed for each pathological entity discussed.

Hepatic focal nodular hyperplasia: colour Doppler ultrasound can be diagnostic

Focal nodular hyperplasia (FNH) is a rare, benign, hepatic mass lesion that is usually found in young adult females. It is sometimes an incidental finding on abdominal sonography or computed tomography. Its appearance on these studies is not characteristic however, thereby creating a diagnostic problem. This report is of a case which showed a centrifugal, spokewheel pattern of pulsatile blood supply on colour Doppler US. This finding, we suggest, is sufficiently diagnostic to avoid the need for further investigation in some patients, and to direct further imaging more appropriately in others.

Pregnancy in a patient with fibrolamellar hepatocellular carcinoma

Pregnancy in a patient with hepatocellular carcinoma is rare. Fibrolamellar hepatocellular carcinoma is a distinct clinicopathologic variant with a better prognosis. We report such a case in which pregnancy was apparently not deleterious.

Hepatic focal nodular hyperplasia: CT and sonographic spectrum

Fifteen patients with pathologically proven focal nodular hyperplasia (FNH) of the liver had abdominal computed tomography (CT) (15) and ultrasound (11). In seven patients, the lesions were incidentally found during gallbladder or renal examination, whereas the other eight had a primary neoplasm and the liver was studied for possible metastasis. In 11 unenhanced CT scans, the ratio of isodense to hypodense lesions was 8 to 3. In 15 contrast-enhanced CT scans, seven were isodense, six were hypodense, and in two, the lesion enhanced (hyperdense). In seven patients a hypodense lesion on unenhanced CT became isodense with contrast injection. Delayed images in three showed the lesions appearing as hypodense in two and displaying a rim of enhancement in one. In one case, unenhanced CT was normal and only enhanced CT showed an area of homogeneous increased density. Ultrasound was done in 11 patients, the lesion was hypoechoic to the liver in five, echogenic in four, and isoechoic in two. Findings of central scar were seen on CT and ultrasound in three cases. Pathologic diagnosis was available in all cases, seven by needle aspiration and eight by surgical resection. In our experience, FNH has many CT and sonographic features that can mimic hemangioma or metastasis. While the presence of a central scar increases the specificity, in a cancer patient, the findings should be interpreted with caution and needle aspiration should be obtained.

Multicystic fibrolamellar hepatocellular carcinoma. CT appearance

An unusual case of fibrolamellar hepatocellular carcinoma (FLHCC) presenting as multiple intrahepatic lesions of cystic appearance on the computed tomography (CT) study is described.