The fibrolamellar variant of hepatocellular carcinoma. Its association with focal nodular hyperplasia

Diagnosis and Follow-up of Incidental Liver Lesions in Children

Incidental liver lesions are identified in children without underlying liver disease or increased risk of hepatic malignancy in childhood. Clinical and imaging evaluation of incidental liver lesions can be complex and may require a multidisciplinary approach. This review aims to summarize the diagnostic process and follow-up of incidental liver lesions based on review of the literature, use of state-of-the-art imaging, and our institutional experience. Age at presentation, gender, alpha fetoprotein levels, tumor size, and imaging characteristics should all be taken into consideration to optimize diagnosis process. Some lesions, such as simple liver cyst, infantile hemangioma, focal nodular hyperplasia (FNH), and focal fatty lesions, have specific imaging characteristics. Recently, contrast-enhanced ultrasound (CEUS) was Food and Drug Administration (FDA)-approved for the evaluation of pediatric liver lesions. CEUS is most specific in lesions smaller than 3 cm and is most useful in the diagnosis of infantile hemangioma, FNH, and focal fatty lesions. The use of hepatobiliary contrast in MRI increases specificity in the diagnosis of FNH. Recently, lesion characteristics in MRI were found to correlate with subtypes of hepatocellular adenomas and associated risk for hemorrhage and malignant transformation. Biopsy should be considered when there are no specific imaging characteristics of a benign lesion. Surveillance with imaging and alpha fetoprotein (AFP) should be performed to confirm the stability of lesions when the diagnosis cannot be determined, and whenever biopsy is not feasible.

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.

Simultaneous Presence of Focal Nodular Hyperplasia and Hepatocellular Carcinoma: Case Report and Review of the Literature

Focal nodular hyperplasia (FNH) is an infrequent benign tumor of the liver that is generally believed to have no potential for malignant transformation; the coexistence of FNH and hepatocellular carcinoma (HCC) has seldom been reported. Here we describe an exceptional case of simultaneous FNH and HCC in the same patient and discuss the clinical and therapeutic management of FNH on the basis of a review of the literature.

Simultaneous occurrence of focal nodular hyperplasia and HNF1A-inactivated hepatocellular adenoma: a collision tumor simulating a composite FNH-HCA

Mixed focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) within a single tumor mass is rarely reported, and most of these cases are examples of tumors with features intermediate between FNH and HCA. Although a few reported cases are probably examples of true mixed tumors, none was evaluated immunohistochemically or confirmed by molecular analysis. We report a mixed FNH and HCA arising in a woman with several HNF1A-inactivated adenomas. Our case is the first case of mixed FNH and HNF1A-inactivated HCA documented by immunohistochemistry.

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.

Fibrolamellar hepatocellular carcinoma: a case report with distinct radiological features

INTRODUCTION

We report a rare case of a 23-year-old male who presented with abdominal discomfort for 15 days. An ultrasound was performed which showed a hypoechoic, heterogenous mass in the left lobe of the liver and distended portal vein, followed by further investigation with computed tomography (CT), MRI, and MRA. Serum alpha-fetoprotein was not elevated and hepatitis B antigen was negative.

METHODS

CT scan depicted a nodular mass in left liver lobe with occlusion of both the central part and the two main branches of intrahepatic portal vein.

RESULT

Biopsy of the liver mass led to a diagnosis of fibrolamellar hepatocellular carcinoma.

CONCLUSION

Fibrolamellar carcinoma is an uncommon variant of hepatocellular carcinoma. The diagnosis is suggested by radiographic studies and is confirmed by histological examination.

Fibrolamellar hepatocellular carcinoma

Fibrolamellar hepatocellular carcinoma (FHLCC) generally occurs in young individuals lacking a background of chronic liver disease and other risk factors for hepatocellular carcinoma. The clinical presentations of FLHCC are generally nonspecific, and the alpha-fetoprotein level is typically within the normal range in most cases. Imaging studies have a major role in clinical diagnosis, but pathology is the gold standard in confirming diagnosis. Pathological characteristics of FLHCC include the presence of tumor cells with a deeply eosinophilic cytoplasm and macronucleoli surrounded by abundant fibrous bands. The most effective treatment for FLHCC is aggressive surgical resection. This comprehensive literature review gives a full account of the clinical, pathological, and molecular features of FLHCC.

Use of X-chromosome inactivation pattern and laser microdissection to determine the clonal origin of focal nodular hyperplasia of the liver

AIM

To determine the clonal origin of the whole lesion and each nodule of focal nodular hyperplasia (FNH) and elucidate its nature, simultaneously comparing the clonal composition with hepatocellular adenoma (HA).

METHODS

Nine FNHs from eight women, two HAs and four hepatocellular carcinomas (HCCs) were examined by clonality assays based on X-chromosomal inactivation mosaicism in females and laser microdissection. Genomic DNA was isolated from each nodule, the whole lesion and surrounding liver parenchyma, pretreated with Hpa II or Hha I, and amplified via nested PCR for phosphoglycerate kinase (PGK) and androgen receptor (AR) genes. The single nucleotide polymorphism at the PGK locus was identified by incubation with Bst XI and agarose gel electrophoresis, and the CAG repeat length polymorphism at AR locus was revealed on denaturing polyacrylamide gels and visualised by silver staining.

RESULTS

Monoclonality was confirmed in both of the two HAs and all of the four HCCs examined, while polyclonality was shown in all nine FNHs as determined by the whole lesions, demonstrating their distinction from neoplastic lesions. A total of 108 nodules, including 96 nodules of altered hepatocytes (NAH) and 12 ordinary regenerative nodules (ORN), were microdissected from eight of the nine FNH lesions. Loss of X-chromosomal inactivation mosaicism was demonstrated in 39 (40.6%) of 96 NAHs, indicating the monoclonal, neoplastic nature. In contrast, polyclonality was demonstrated in all of the 12 ORNs and the surrounding liver parenchyma.

CONCLUSIONS

FNH is composed of numerous NAHs and ORNs. The whole lesion shows a polyclonal cell composition, but neoplastic transformation has occurred in some of the nodules. Clonal assay is useful for its distinction from HA, and sampling the whole or larger part of the lesion is necessary.

Focal nodular hyperplasia of the liver in patients previously treated for pediatric neoplastic diseases

The discovery of a liver nodule during postcancer follow-up suggests malignancy recurrence. However, patients previously treated for pediatric cancers are at greater risk of developing benign hepatic tumors, raising the problems of getting an accurate noninvasive diagnosis. Here we report 3 cases of focal nodular hyperplasia of the liver in patients previously treated for pediatric neoplastic diseases. Radiologic findings and needle-biopsies remained insufficient in 2 cases to rule out metastasis or a potentially threatening tumor. Only surgical resection led to positive diagnosis and prevented complications. However, a review of the literature shows that if the nodule presents with typical features of focal nodular hyperplasia a close imaging follow-up is all that is recommended.

Indication for treatment and long-term outcome of focal nodular hyperplasia

INTRODUCTION

Unlike malignant liver tumours, the indications for hepatic resection for benign disease are not well defined. This is particularly true for focal nodular hyperplasia (FNH). Here we summarize a single-centre experience of the diagnosis and management of FNH.

MATERIALS AND METHODS

Using a prospectively collected database, a retrospective analysis of consecutive patients who were managed at our centre for FNH between January 1997 and December 2006 was performed.

RESULTS

The cohort was divided into two groups of patients: those who were managed surgically (n=15) and those managed conservatively (n=37). There was no correlation between tumour size and number of lesions with oral contraceptive use (p=0.07 and 0.90, respectively) and pregnancy (p=0.45 and 0.60, respectively). However, tumour size (p=0.006) and number of lesions (p=0.02) were associated with the occurrence of pain in these patients. Pain was the commonest symptom of patients (13/15) who were managed surgically. All patients underwent radiological imaging before diagnosis. The sensitivities of ultrasound, CT scanning and MRI scanning in characterizing these lesions were 30%, 70% and 87%, respectively. There were no postoperative deaths and three postoperative complications that were successfully managed non-operatively. With a median follow-up of 24 months in the surgically treated group, one patient has developed recurrent symptoms of pain. CONCLUSION. In this series, there was no mortality directly due to the surgical procedure and a modest morbidity, justifying surgical resections in selected patients.

A case of hepatocellular carcinoma arising within large focal nodular hyperplasia with review of the literature

Focal nodular hyperplasia (FNH) is a relatively rare benign hepatic tumor, usually presenting as a solitary lesion; however, multiple localizations have also been described. The association of FNH with other hepatic lesions, such as adenomas and haemangiomas has been reported by various authors. We herein report a case of a hepatocellular carcinoma arising within a large focal nodular hyperplasia, in a young female patient.

Focal nodular hyperplasia with concomitant hepatocellular carcinoma: a case report and clonal analysis

This report describes a hepatocellular carcinoma (HCC) with concomitant focal nodular hyperplasia (FNH) in a 56 year old Chinese man. There were two well circumscribed tumours measuring 3 x 2.5 x 2 cm and 2 x 1.5 x 1.5 cm. The larger mass was grey and soft with a small area of bleeding and necrosis and an intact capsule. The smaller mass was yellow and had no capsule. Clonal analysis was carried out to clarify the relation between the HCC and the adjacent FNH. The clonal analysis was based on the methylation pattern of the polymorphic X chromosome linked androgen receptor gene (HUMARA). In FNH, after HpaII digestion, the allelic bands showed two well defined peaks. The intensity of the two peaks in the DNA from cirrhotic tissue did not differ significantly, consistent with a random pattern of X chromosome inactivation. However, in HCC, after HpaII digestion, the allelic bands differed significantly in intensity. Therefore, there was a typical polyclonal pattern of inactivation in FNH but the HCC was interpreted as being monoclonal.

Hepatic focal nodular hyperplasia in children previously treated for a solid tumor. Incidence, risk factors, and outcome

BACKGROUND

The detection of hepatic nodules, particularly in patients treated for a previous malignancy, raises a diagnostic dilemma. Focal nodular hyperplasia (FNH) of the liver is an uncommon, benign tumor in children and must be differentiated from malignant hepatic lesions. The etiology of FNH is obscure, and its pathogenesis is poorly understood. FNH may be a reaction to localized vascular abnormalities and circulatory disturbances. The goal of the current study was to identify risk factors for the occurrence of FNH in children who had received prior treatment for a malignant tumor.

METHODS

The current retrospective study examined 14 cases of FNH in pediatric patients who previously had been treated for a malignancy. Diagnosis was based on clinical and radiologic findings and was proven histologically in four cases.

RESULTS

FNH lesions were discovered by chance during routine examination in 78% of patients. The incidence of FNH was particularly high in the current series (0.45%) compared with the incidence in the general pediatric population. High doses of alkylating agents (e.g., busulfan or melphalan), venoocclusive disease, and liver radiotherapy may be responsible for injury to the vascular endothelium and subsequent localized circulatory disturbances. FNH is characterized by the absence of complications after its detection; therefore, only close follow-up is recommended.

CONCLUSIONS

FNH appears to be a late complication of an iatrogenic vascular disease in children with a history of malignancy.

Hepatocellular carcinoma in a patient with focal nodular hyperplasia

BACKGROUND

Focal nodular hyperplasia is an uncommon liver tumour that typically requires no therapeutic intervention.

CASE OUTLINE

A 43-year-old woman with a 20-year history of oral contraceptive use presented with symptomatic bilateral liver masses. Biopsy revealed hepatocellular carcinoma in the right hemiliver and focal nodular hyperplasia in the left hemiliver. At operation,t he patient was noted to have multiple liver nodules bilaterally, and all intraoperative biopsies were consistent with focal nodular hyperplasia including a biopsy taken from the region that demonstrated carcinoma preoperatively. Because of the earlier biopsy results and the patient's preoperative symptoms, a right hemihepatectomy was performed. Final pathology revealed hepatocellular carcinoma directly adjacent to an area of focal nodular hyperplasia, as well as multiple other areas of hyperplastic liver tumour.

DISCUSSION

Although focal nodular hyperplasia is believed to be benign, few studies have followed patients with this tumour beyond three years. Longer-term follow-up studies are needed to determine the natural history of focal nodular hyperplasia, potentially focussing on a subset of patients with either diffuse tumours or prolonged oral contraceptive use.

Focal nodular hyperplasia of the liver: a comprehensive pathologic study of 305 lesions and recognition of new histologic forms

Atypical histologic variants of focal nodular hyperplasia have been reported and are sometimes difficult to recognize. To characterize the morphologic spectrum of focal nodular hyperplasia, we studied 305 lesions surgically resected from 168 patients. Clinicomorphologic correlations were established by statistical analyses. The patients included 150 women and 18 men (sex ratio, 8:1; median age, 38 years). One hundred twenty-eight (76.2%) patients had solitary lesions, and 40 (23.8%) had 2 to 30 lesions. All 305 lesions measured 1 mm to 19 cm in diameter. Only 49% of these lesions had one to three macroscopic scars. Histologically, 245 (80.3%) lesions were of classical form, and 60 (19.7%) lesions were nonclassical. The latter were classified as focal nodular hyperplasia of telangiectatic form (47 lesions), of mixed hyperplastic and adenomatous form (five lesions), and with atypia of large cell type (eight lesions). Several benign or malignant tumors were found in association with these lesions. This large retrospective series of focal nodular hyperplasia shows the relative incidence of its classical and nonclassical forms. The absence of a central scar could explain the difficult preoperative diagnosis of some of the cases. The morphologic diagnostic criteria in this study require further prospective evaluation.

Cytologic aspect of fibrolamellar hepatocellular carcinoma in fine-needle aspirates

This is a review of the cytologic and clinicopathological findings seen in a series of six fibrolamellar hepatocellular carcinomas (FL-HCC) studied by means of fine-needle aspiration (FNA). A comparison of several cellular measurements (cell, nuclear and nucleolar sizes, and N/C ratios) of FL-HCC, ordinary hepatocellular carcinoma (O-HCC), and normal hepatocytes was also carried out in order to find out if these figures could be of help in the cytologic diagnosis. Aspirates were made up of a rather monotonous population of large discohesive cells resembling the morphology of the oncocytes seen in thyroid aspirates; trabecular arrangement of tumor cells was not observed. Cytoplasmic pale bodies and hyaline cytoplasmic bodies were seen in variable quantities. Microbiopsies displaying the fibrolamellar pattern were observed in four cases. FL-HCC individual tumor cells were larger than individual O-HCC tumor cells (P < 0.001), as were nuclear (P < 0.007) and nucleolar sizes (P < 0.001), but N/C ratio of O-HCC was higher than the N/C ratio of FL-HCC (P < 0.005). Based on the findings, a single cell aspirated from an FL-HCC is three times the size of a normal hepatocyte and 1.60 times the size of a single cell aspirated from a well-differentiated O-HCC. The cytologic findings of FL-HCC are very characteristic and permit a correct diagnosis of this liver malignancy, provided the cytopathologist is aware of the clinical, demographic, CT-image, biochemical, and pathological features of this neoplasm. Diagn. Cytopathol. 21:180-187, 1999.

Regression of focal nodular hyperplasia of the liver after oral contraceptive discontinuation

There is uncertainty regarding the role, if any, of oral contraceptive steroids in the development of focal nodular hyperplasia of the liver. A case of focal nodular hyperplasia of the liver diagnosed by scintigraphy in a 33-year-old woman is presented. The lesion regressed in a dramatic way after oral contraceptive discontinuation. This case report suggests that oral contraceptives may influence the natural history of focal nodular hyperplasia of the liver, and that a trophic effect on the liver lesion is quite possible.

Management of focal nodular hyperplasia and hepatocellular adenoma in young women: a series of 41 patients with clinical, radiological, and pathological correlations

Preoperative distinction between focal nodular hyperplasia (FNH) that should be managed conservatively and hepatocellular adenoma (HA) that should be resected remains difficult. The result is controversial management of these patients. The aims of this study were to report the value of modern imaging procedures for noninvasive diagnosis of these lesions, to assess the value of intraoperative frozen section studies, and to propose a management strategy in those patients. Forty-one consecutive women with FNH (35 cases) or HA (6 cases) treated at our institution between 1985 and 1992 were studied. New imaging techniques, including enhanced magnetic resonance imaging (MRI) and color Doppler ultrasonography (US), were prospectively appraised in addition to usual techniques. Histological examination of surgical specimens was obtained in all cases. A sixfold increase in the number of patients with FNH was observed during this study, whereas the number of patients with HA did not change. FNHs were incidental US findings in 74% of the cases. The best imaging procedure in the diagnosis of FNH was enhanced MRI with a sensitivity of 70% and a specificity of 98%. Color Doppler US was a useful adjunct. Intraoperative frozen section studies were performed in 16 patients with 19 tumors with a sensitivity of 89% and a specificity of 100%.(ABSTRACT TRUNCATED AT 250 WORDS)

Type La glycogen storage disease with focal nodular hyperplasia in siblings

Glycogen storage disease type I (GSD-I) is an inherited disorder that is due to a glucose-6-phosphatase (G6Pase) deficiency. There have been recent reports of hepatocellular tumors in adults with this disease. Hepatic adenoma is the most common tumor described but others, including hepatocellular carcinomas, hepatoblastomas, and focal nodular hyperplasia (FNH) have been reported. FNH of the liver is a rare benign lesion that has been reported in eight patients with GSD-I. Three of these eight patients, in addition to the patient in our study, had been treated with portacaval shunts. When these patients were compared with patients who had not received such treatment, it appeared that the portacaval shunts may have induced the development of FNH and may have been associated with earlier complications. FNH is a benign tumor that may coexist with adjacent fibrolamillar carcinomas and/or adenomas and requires careful follow-up.

Nodular hyperplasia surrounding fibrolamellar carcinoma: a zone of arterialized liver parenchyma

We report a case of acetaminophen-induced liver necrosis in a 14-year-old girl. At autopsy, a 9 cm subcapsular nodule was present in the right lobe of the liver which showed distinct zonation: a central greyish white area of fibrolamellar carcinoma with a peripheral fleshy, tan-coloured rim ranging from 1 to 2 cm in thickness. This peripheral zone consisted of nodular, hyperplastic parenchyma resembling the changes seen in focal nodular hyperplasia, and stood out from the adjacent necrotic parenchyma. The sparing of this zone from the deleterious effects of acetaminophen provides indirect evidence of a predominantly arterial rather than portal blood supply to this region. The arterial supply was most probably derived from the tumour vasculature and may explain the parenchymal hyperplasia sometimes reported adjacent to a fibrolamellar carcinoma. Awareness of this phenomenon is essential when evaluating a needle biopsy, as sampling of this region may lead to a false negative diagnosis.

Hepatic neoformations

The aim of the paper is an accurate histologic description and illustration of those liver lesions that are usually summarized under the heading of "hepatic tumors and related subjects". For in some cases it may be unclear or at least controversial, whether the individual lesion is indeed an autonomous neoplasia or a malformation, regeneration or hyperplasia, the indifferent master term of neoformation is introduced, based on the fact that all of them are characterized by a cellular multiplication. According to common definitory practice the survey distinguishes between mesenchymal (angiomatous and non angiomatous) and epithelial neoformations. Among the latter hepatocellular and cholangiocellular types are distinguished, the criterium for differentiation being a phenomenological one, which is by no means identical with a histogenetical statement. The definition of subgroups mostly adheres to current nomenclatory usage; only occasionally--in the group of endothelial tumors--a novel term is employed, in view of brevity and coordination with the overall system of neoformations.

Contribution of CT to characterization of focal nodular hyperplasia of the liver

Our personal series of 20 cases of focal nodular hyperplasia (FNH) of the liver is presented. All lesions were studied with computed tomography (CT), 16 of which with surgical control. Retrospective evaluation of the CT features of the identified FNH, along with those of five hepatocellular adenomas (HCA) and 30 hepatocellular carcinomas (HCC), allowed the definition of specific patterns leading to a correct characterization of FNH in 78% of cases. This greatly reduced the diagnostic errors, with the sole exception of patients with fatty liver in whom nuclear medicine may eventually provide a correct characterization. Fine-needle biopsy is thus only necessary in the dubious cases. A precise diagnostic workup of FNH is necessary, since it may avoid the surgical intervention.

Focal nodular hyperplasia of the liver: results of treatment and options in management

Twenty two patients (19 females) with focal nodular hyperplasia were seen between 1973 and 1989. Five were children, and all the adults were aged under 42 years (median 33 years). Fourteen patients (64%) were symptomatic on presentation. Twelve of the 14 adult women had taken the oral contraceptive pill. Twelve patients, nine of whom were symptomatic, underwent hepatic resection shortly after presentation. There were no deaths or major complications, and all remain well on follow up. Four patients underwent either hepatic artery embolisation or ligation. After an interval of six to 10 years they were asymptomatic and only one has histological evidence of residual focal nodular hyperplasia. Of five patients initially treated conservatively, two were asymptomatic and have remained so for three and 13 years. One of the three symptomatic patients became symptom free after stopping the contraceptive pill. The management of focal nodular hyperplasia requires a flexible approach. Lesions which are asymptomatic can be observed with regular ultrasound and treated if they enlarge or become symptomatic. Symptomatic patients who present while taking the contraceptive pill can also have a trial of conservative treatment. Other symptomatic patients, including those who previously took the pill, are best treated by surgical resection, and, where this is not possible, by embolisation.

Primary liver neoplasms: evaluation of proliferative index using MoAb Ki67

Thirty-two cases of primary liver neoplasms comprising 12 benign, 15 malignant, and 5 cases with equivocal histopathological features between benign and malignant have been investigated using monoclonal antibody (MoAb) Ki67, which reacts with a nuclear protein expressed in the G1, G2, S, and M phases of the cell cycle. The Ki67 score (positive cells/total neoplastic cells) seems to correlate to the classes of lesions tested. In the hepatocellular carcinoma (HCC) group, the percentage of labelled nuclei, ranging from 15 to 50 per cent, showed a good correlation with Edmondson-Steiner's histological tumour grade. A percentage of positive cells similar to that of the proved low-grade HCCs was detected in the five neoplastic lesions in which the routine histopathological criteria of malignancy were not fulfilled. The benign neoplasms showed a very low growth fraction, similar to that of normal or cirrhotic tissues. The use of the Ki67 score seems to offer useful information about the biological behaviour of some liver masses and may help in the differential diagnosis of hepatocellular adenoma versus carcinoma.