Natural history of focal nodular hyperplasia of the liver: an ultrasound study

A Review of Benign Hepatic Tumors and Their Imaging Characteristics

This paper concisely reviews the benign hepatic tumors most commonly encountered by clinicians. It includes the epidemiology, pathology, and imaging characteristics of hepatic hemangiomas, focal nodular hyperplasia (FNH), and hepatic adenomas (HAs).

Surgical indications for focal nodular hyperplasia of the liver: Single-center experience of 48 adult cases

Backgrounds/Aims

Focal nodular hyperplasia (FNH) is one of the most common benign tumors of the liver. There is still a lack of evidence on surgical indications for FNH. This study intended to analyze the surgical indications for FNH.

Methods

We analyzed 48 cases of FNH diagnosed after hepatic resection.

Results

Common reasons leading to surgical resection were diagnostic uncertainty (n=31), and persistent symptoms (n=8). None of our patients had a past history of contraceptive use. Percutaneous biopsy was performed in 14 patients and FNH was diagnosed in nine patients, and hepatic adenoma, hepatocellular carcinoma, plasmacytoma, angiosarcoma, and atypical hepatocellular proliferation in one patient each. Minor hepatectomy (n=37) was performed more frequently than major hepatectomy (n=11). Open hepatectomy (n=29) was performed more frequently than laparoscopic hepatectomy (n=19), but laparoscopic and minimally-invasive surgery was frequently performed during the late phase of the study period. Postoperative surgical complications occurred in two patients (4.1%).

Conclusions

FNH can be diagnosed by imaging studies, but surgical treatment may be considered in cases of diagnostic uncertainty or persistent symptoms.

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.

Benign solid tumors of the liver: management in the modern era

BACKGROUND

Recently, there has been a growing interest in solid benign liver tumors as the understanding of the pathogenesis and molecular underpinning of these lesions continues to evolve. We herein provide an evidence-based review of benign solid liver tumors with particular emphasis on the diagnosis and management of such tumors.

METHODS

A search of all available literature on benign hepatic tumors through a search of the MEDLINE/PubMed electronic database was conducted.

RESULTS

New diagnostic and management protocols for benign liver tumors have emerged, as well as new insights into the molecular pathogenesis. In turn, these data have spawned a number of new studies seeking to correlate molecular, clinicopathological, and clinical outcomes for benign liver tumors. In addition, significant advances in surgical techniques and perioperative care have reduced the morbidity and mortality of liver surgery. Despite current data that supports conservative management for many patients with benign liver tumors, patients with severe preoperative symptomatic disease seem to benefit substantially from surgical treatment based on quality of life data.

CONCLUSION

Future studies should seek to further advance our understanding of the underlying pathogenesis and natural history of benign liver tumors in order to provide clinicians with evidence-based guidelines to optimize treatment of patients with these lesions.

Acute nontraumatic liver lesions

The principal conditions requiring emergency/urgent intervention in patients with nontraumatic liver lesions are hemorrhage (with or without tumor rupture), rupture of hydatid cysts (with or without infection), complications arising from liver abscesses or congenital liver cysts, rupture related to peliosis hepatis, and in rare cases spontaneous hemorrhage. This article examines each of these conditions, its appearance on ultrasound (the first-line imaging method of choice for assessing any urgent nontraumatic liver lesion) and indications for additional imaging studies.

[Overview: liver tumors]

Since the introduction of abdominal ultrasound liver lesions have been increasingly detected. Being usually diagnosed by chance these lesions create psychological stress among patients because a potential malignant disease has to be taken into consideration. The increasing use of oral contraceptives with high estrogen doses starting in the 1980s led to a rising incidence of adenomas, whose natural history differed from those described in surgical and autoptic studies. This fact brought about a change towards a modern pathophysiologic and prognostic differentiation. Current histologic and molecular biological techniques are able to distinguish benign adenomas from those with malignant potential.

Understanding the natural history of focal nodular hyperplasia in the liver with MRI

Aims:

To determine the incidence of natural growth or regression of focal nodular hyperplasia (FNH) in the liver.

Material and Methods:

We retrospectively included 120 consecutive patients who were diagnosed to have FNH on MRI. The mean follow-up duration was 19 months (range: 6–64 months). There were 25 men and 95 women (age range: 18–80 years; mean: 45 years). There were 167 FNH lesions in the 120 patients. MRI images were retrospectively reviewed for interval growth or regression of FNH. The maximum size of the lesions was measured on axial arterial-phase images of the initial and the last MRI examinations. An interval increase or decrease in diameter of over 10% of the initial diameter was considered as positive growth or regression, respectively. The use of Oral contraceptives was also documented.

Results:

Interval growth was seen in 25/167 nodules (15%) over 7-48 months (mean: 21 months), with increase in size of 0.2-1.7 cm (mean: 0.6 cm) and percentage change of 10.5-340% (mean: 64%). Interval regression was seen in 13/167 (8%) of nodules over 7-63 months (mean: 22 months), with decrease in size of 0.2-0.9 cm (mean: 0.5 cm) and percentage change of 10.4-60% (mean: 24%).Five of 17 (29%) female patients with growing FNH and 25/78 (32%) female patients with non-growing FNH had a history of intake of oral contraceptives (P=0.83).

Conclusions:

Although FNH is benign and of no clinical significance, a substantial percentage of FNH shows interval growth or regression on long-term follow-up with MRI.

Two cases of near-complete regression of focal nodular hyperplasia of the liver: Case reports and review of the literature

While regression of focal nodular hyperplasia of the liver is not uncommon, reports of near-complete involution or regression of these lesions are rare. We report two cases of focal nodular hyperplasia that underwent near-complete regression-one in a 27-year-old female that regressed over a period of 4 years, and one in a 46-year-old female that regressed over a 7-year period. Both patients discontinued use of exogenous estrogens between the diagnosis of focal nodular hyperplasia and its subsequent regression. Although contemporary cross-sectional imaging has improved the ability to detect and follow these lesions, few studies examining the natural history of focal nodular hyperplasia have been conducted. We discuss pertinent imaging findings on magnetic resonance imaging and computed tomography, and review the literature on regression of focal nodular hyperplasia and the effects of endogenous hormones and exogenous hormone therapy.

Recent advances in cytogenetics and molecular biology of adult hepatocellular tumors: implications for imaging and management

Focal nodular hyperplasia (FNH), hepatocellular adenoma (HCA), and hepatocellular carcinoma (HCC) compose hepatocellular neoplasms that occur in adults. These tumors demonstrate characteristic epidemiologic and histopathologic features and clinical and imaging manifestations. HCAs are monoclonal neoplasms characterized by increased predilection to hemorrhage or rupture and occasional transformation to HCC. On the other hand, FNH is a polyclonal tumorlike lesion that occurs in response to increased perfusion and has an indolent clinical course. Up to 90% of HCCs occur in the setting of cirrhosis. Chronic viral hepatitis (hepatitis B and hepatitis C) infection and metabolic syndrome are major risk factors that can induce HCCs in nonfibrotic liver. Recent advances in pathology and genetics have led to better understanding of the histogenesis, natural history, and molecular events that determine specific oncologic pathways used by these neoplasms. HCAs are now believed to result from specific genetic mutations involving TCF1 (transcription factor 1 gene), IL6ST (interleukin 6 signal transducer gene), and CTNNB1 (β catenin-1 gene); FNHs are characterized by an "imbalance" of angiopoietin. While the β catenin signaling pathway is associated with well- and moderately differentiated HCCs, mutations involving p53 (tumor protein 53 gene), MMP14 (matrix metalloproteinase 14 gene), and RhoC (Ras homolog gene family, member C) are associated with larger tumor size, higher tumor grade with resultant shortened tumor-free survival, and poor prognosis. Fibrolamellar carcinoma (FLC), a unique HCC subtype, exhibits genomic homogeneity that partly explains its better overall prognosis. On the basis of recent study results involving cytogenetics and oncologic pathways of HCCs, novel drugs that act against molecular targets are being developed. Indeed, sorafenib (a multikinase inhibitor) is currently being used in the successful treatment of patients with advanced HCC. Characterization of genetic abnormalities and genotype-phenotype correlations in adult hepatocellular tumors provides better understanding of tumor pathology and biology, imaging findings, prognosis, and response to molecular therapeutics.

Conservative and operative management of benign solid hepatic tumours: a successful stratified algorithm

BACKGROUND

The progress of modern imaging studies has improved the diagnostic approach of benign liver tumours, leading to a tailored approach with increased conservative management.

METHODS

One hundred and thirty-two patients suffering from benign hepatic tumours were enrolled in this study, including an operative (group I, 49 patients) and a conservative (group II, 83 patients) management. Patients' tumour and treatment features were analyzed.

RESULTS

The mean patients' age was 39 years. Indication for resection based on diagnosis of tumour nature (hepatic cell adenoma or uncertain diagnosis) and significant tumour-related abdominal pain was 15% out of 33 patients with hepatic haemangioma, 21.7% out of 60 patients with focal nodular hyperplasia and 78.4% out of 37 patients with hepatocellular adenoma. Mortality was nihil in group I. Complications and transfusion rates were related to the performance of major hepatectomy, when required for huge tumours. With a 95.5% of complete patients' follow-up during a mean of 92 months in group I and 87 months in group II, no misdiagnosis or evolution towards malignancy was encountered. Interestingly, 87.9% of all observed benign liver tumours remained stable, decreased in size or disappeared. None of the remaining lesions required surgery.

CONCLUSION

A restrictive policy of surgical management of benign liver tumours based on clinical symptoms, tumour size and nature on imaging studies (including dubious lesions) and tumour biopsies in selected cases is safe and reliable with a low-operative mortality in resected patients and satisfactory disease-control in the vast majority of observed benign liver tumours.

Spontaneous regression of focal nodular hyperplasia: a pathological report

Focal nodular hyperplasia (FNH) is a benign tumour of the liver, occurring in 0.6-3% of the general population. Most lesions are diagnosed incidentally. With the increasing use and improvement of diagnostic imaging, FNH is being observed more often. It has been shown, using radiological approaches, that most FNH remain stable, or even regress, over a long follow-up period. In addition, it is extremely rare that FNH were discovered in elderly. However, to our knowledge, there is no pathological report illustrating the regression of FNH. We report here a case showing the pathological changes occurring during the regression phase of FNH, with dense fibrous tissue mixed with arteries replacing hepatocytes nodules.

Focal nodular hyperplasia in children: clinical features and current management practice

BACKGROUND

Although nonoperative management is an accepted practice for most adults with focal nodular hyperplasia (FNH), questions remain about the safety and feasibility of this strategy in children. Our aim was to review the clinical features of children with FNH and determine current management patterns.

METHODS

We reviewed records of all children and adolescents with FNH managed at our institution from 1999 to 2009 and performed a MEDLINE search to identify all published cases of FNH in the pediatric population.

RESULTS

A total of 172 patients with FNH were identified, including 11 at our institution. The median age at diagnosis was 8.7 years and 66% were female. Median tumor size was 6 cm, and 25% had multiple lesions. Thirty-six percent were symptomatic at presentation. Twenty-four percent had a history of malignancy. Management included resection (61%), biopsy followed by observation (21%), and observation alone (18%). Indications for resection included symptoms (48%), inability to rule out malignancy (24%), tumor growth (15%), and biopsy-proven concurrent malignancy (9%).

CONCLUSIONS

Although FNH is a benign lesion that is typically managed nonoperatively in adults, most children with FNH currently undergo resection because of symptoms, increasing size, or inability to confidently rule out malignancy.

Detection Of Focal Liver Lesions In Cirrhotic Liver Using Contrast-Enhanced Ultrasound

Patients with liver cirrhosis are at increased risk of hepatocellular carcinoma (HCC). Conventional or baseline ultrasound (BUS) is often used as the first-line tool for HCC surveillance or detection, but the accuracy of BUS in HCC detection or differentiation from other focal liver lesions (FLLs) is limited. Contrast-enhanced ultrasound (CEUS) represents a recent revolution in the field of ultrasonography and it has become increasingly important in the detection and evaluation of FLLs. In CEUS, HCC typically exhibits arterial hyper-enhancement and portal-venous washout represented by hypo-enhanced lesions in the portal venous and late phases. The detection rate of HCC was significantly higher with CEUS compared with BUS. Even regenerative or some dysplastic nodules may exhibit arterial hyper-enhancement as they are differentiated from HCC by its iso-enhancing pattern in portal and late phases. The contrast-enhancement patterns of other different types of benign and malignant FLLs, as well as their detection rates with CEUS, were also discussed.

Diagnosis and treatment of benign focal liver lesions

BACKGROUND

With the routine use of improved imaging modalities, more benign liver lesions are detected nowadays. An accurate characterization of these incidental lesions may be a challenge, and frequently a biopsy or even unnecessary surgery is being performed. However, these interventions are not always to the benefit of the patient.

METHODS

A Medline search of studies relevant to imaging diagnosis and management of the most common, benign, solid and non-solid liver lesions was undertaken. References from identified articles were handsearched for further relevant articles. The authors' own experiences with benign liver lesions were also taken into account.

RESULTS

Although atypical imaging features are the exception rather than the rule, it is sometimes difficult to differentiate between benign and malignant lesions, and knowledge of their imaging features is essential if unnecessary work-up is to be avoided. The use of tissue-specific contrast media, which has clearly improved the accuracy of highly advanced radiological techniques, may be helpful during differential diagnosis. Once having established an accurate diagnosis, surgery is rarely indicated for a benign liver lesion because of its asymptomatic nature.

CONCLUSION

Knowledge of imaging features and a clear management strategy during diagnostic work-up, emphasizing the indications for surgery, will minimize the number of patients who have to undergo biopsy or unnecessary surgery.

Natural course of hepatic focal nodular hyperplasia: a long-term follow-up study with sonography

PURPOSE

We aimed to investigate the natural course of hepatic focal nodular hyperplasia (FNH) in a long-term follow-up study with sonography.

METHOD

This study comprised 30 patients (24 women and 6 men) with 34 FNHs. Diagnosis of FNH was made using color Doppler sonography, contrast-enhanced CT, or MRI in combination with needle biopsy. Patients were followed every 3 to 6 months with sonography. Regression or progression of tumor was defined as a change of over 30% in maximal diameter. Disappearance was defined as no vizualization of the tumor on at least 3 follow-up sonographic examinations.

RESULTS

Thirty-four FNHs were followed over a mean period of 42 months (range, 7-95 months). Twenty-four lesions (70.6%) were stable in size, 1 (2.9%) progressed, and 9 (26.5%) regressed. Of those that regressed, 6 (17.6%) disappeared over a mean period of 59 +/- 30 months (range, 20-95 months). Older age (OR 1.26, 95% CI 1.02-1.56; p < 0.05) and longer follow-up time (OR 1.11, 95% CI 1.01-1.21; p < 0.05) were the independent factors associated with complete regression of FNH.

CONCLUSION

Most FNHs were stable or regressed/disappeared after a long follow-up period. Based on the benign course, conservative treatment for asymptomatic FNH should be advocated.

Management and surgical treatment for focal nodular hyperplasia in children

Focal nodular hyperplasia (FNH) is rare in pediatric liver tumor. To investigate the experience in the appropriate management of pediatric FNH, the records of consecutive children who were managed at our institute from 2000 to 2007were reviewed for FNH. There were four males and nine females whose ages ranged from 26 months to 18 years with a mean of 11.7 years. FNH in most children was detected by medical examination for abdominal pain (61.5%) or other symptoms. All the 13 pediatric patients underwent liver resection. There was no operative death or postoperative complications. The children were regularly followed up ranging from 2 to 85 months and they were healthy without recurrence. For pediatric FNH patients with clinical symptoms or indefinite diagnosis, it is suggested that active surgical treatment by hepatectomy should be performed.

The role of contrast-enhanced ultrasound for focal liver lesion detection: an overview

The development of new ultrasound (US) contrast agents and sonographic techniques has considerably improved the possibilities of ultrasound in the assessment of liver tumors. An overview is given on diagnostic potential of contrast-enhanced US (CEUS) and real-time low mechanical index technique in the detection of various focal liver lesions compared with computed tomography, magnetic resonance imaging or intraoperative US. In two of our own studies that included 100 patients each we showed an increase of correct findings in CEUS compared with B-mode US from 64% to 87% and from 67% to 84% as confirmed by intraoperative evaluation of the liver. Especially after chemotherapy and in the case of small metastases, significantly more metastases were correctly detected by CEUS compared with B-mode US. These results and clinical study results in the literature show that CEUS allows tumor detection and direct visualization of the tumor vascularity and put contrast-enhanced sonography among recommended noninvasive imaging methods for focal liver lesions with improvements in diagnostic strategy.

Diagnosis and management of hepatic focal nodular hyperplasia

Focal nodular hyperplasia (FNH) is the second most common benign tumor of the liver, after hemangioma. It is generally found incidentally and is most common in reproductive-aged women, but it also affects males and can be diagnosed at any age. Patients are rarely symptomatic, but FNH sometimes causes epigastric or right upper quadrant pain. The main clinical task is to differentiate it from other hypervascular hepatic lesions such as hepatic adenoma, hepatocellular carcinoma, or hypervascular metastases, but invasive diagnostic procedures can generally be avoided with the appropriate use of imaging techniques. Magnetic resonance (MR) imaging is more sensitive and specific than conventional ultrasonography (US) or computed tomography (CT), but Doppler US and contrast-enhanced US (CEUS) can greatly improve the accuracy in the diagnosis of FNH. Once a correct diagnosis has been made, in most cases there is no indication for surgery, and treatment includes conservative clinical follow-up in asymptomatic patients.

The value of laparoscopic liver surgery for solid benign hepatic tumors

BACKGROUND

Laparoscopic liver resection (LLR) has gained wide acceptance for various liver resection procedures, mainly for benign diseases. However, only small series have been reported from a few selected centers.

METHODS

Between January 2001 and January 2006, a total of 629 liver resections were performed at our institution. The indication was solid benign liver tumor in 56 (8.9%) patients. LLR was performed in 20 (35.7%) cases. Data from the LLR group were compared with those from a consecutive control group undergoing open liver surgery (OS) for similar indications in a matched-pair analysis during the same period. The pairs were matched as closely as possible for age, gender, American Society of Anesthesiologists (ASA) score, indication for resection, and type and location of the lesions. The endpoint was to investigate overall morbidity and outcome.

RESULTS

All patients but one are alive and well after a mean follow-up of 35 months (range 10-60 months). Conversion laparotomy was required in two out of 20 (10%) cases for uncontrolled bleeding (one requiring temporary hemodialysis). LLR was characterized by faster time to first oral intake and shorter hospital stay compared to OS (p = 0.001 and 0.008, respectively). Incisional hernias (25%) were only recorded in the OS (p = 0.047 vs. LLR). Overall morbidity was 45% in OS versus 20% in LLR (p = 0.3).

CONCLUSIONS

LLR significantly reduced time to oral intake, hospital stay, and incisional hernias compared to OS. Bleeding is a major risk and should be carefully considered when resecting benign tumors. In the hands of expert surgeons, LLR may become the gold standard for the resection of benign liver tumors located in the anterior and lateral sectors and for minor hepatic resections.

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 in a child with Beckwith-Wiedemann syndrome

Beckwith-Wiedemann Syndrome (BWS) is associated with somatic overgrowth and a high risk for embryonal tumors, including hepatoblastoma, a highly malignant liver tumor of childhood. Focal nodular hyperplasia (FNH), on the other hand, is a benign tumor of the liver that is uncommon in childhood. Herein we describe a case of FNH in a child with BWS, the first such report in the literature.

Focal nodular hyperplasia after busulfan treatment

The case of a 48-year-old woman in whom focal nodular hyperplasia of the liver developed after busulfan therapy was administered for essential thrombocytosis is described. Focal nodular hyperplasia is a reactive disorder related to a circulation disorder. The close temporal relation between the haematological disease, busulfan treatment and the appearance of hyperplastic diseases of the liver in our patient supports the possibility that the association of the events might not be casual.

Focal nodular hyperplasia of the liver: usefulness of superparamagnetic iron oxide-enhanced magnetic resonance imaging

This report describes the use of superparamagnetic iron oxide-enhanced magnetic resonance imaging to diagnose fibronodular hyperplasia of the liver in a 12-year-old girl.

Drug induced hepatic focal nodular hyperplasia

Focal nodular hyperplasia, an uncommon benign hepatic tumor, has been reported following ingestion of various drugs and chemical agents. The authors report a case of a young girl who developed such lesion following ingestion of anti-tuberculosis drugs for the treatment of her abdominal tuberculosis.

High prevalence of hepatic focal nodular hyperplasia in subjects with hereditary hemorrhagic telangiectasia

A vascular pathogenesis of hepatic focal nodular hyperplasia (FNH) has been suggested; this study was aimed to evaluate in families with hereditary hemorrhagic telangiectasia (HHT) the prevalence of FNH, relating it to presence and stage of hepatic vascular malformations (VMs). Fifty-two HHT families underwent a screening program including abdominal Doppler sonography (US) searching for hepatic VMs; we classified them as minimal, moderate and severe, depending on the number and degree of abnormalities found by Doppler US. Presence of focal liver lesions was recorded. Diagnosis of FNH was made if at least two examinations, whether color Doppler US, liver scintigraphy, dynamic computed tomography (CT) or magnetic resonance (MR), showed suggestive findings. FNH was found in five out of 274 subjects (1.8%). All five were affected by HHT. Thus, percentage related to the group of affected patients increased to 2.9; 4/5 presented severe liver VMs. Female-to-male ratio was 4:1. FNH was single in three cases; tumor size ranged between 20 and 90 mm. During follow-up, no lesion showed a reduction in size, three showed an increase. Prevalence of FNH in patients with HHT is far greater than that reported in the general population; Doppler US role in its diagnosis and follow-up is highlighted.

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.

Congenital extrahepatic portocaval shunt (Abernethy type 2), huge liver mass, and patent ductus arteriosus--a case report of its rare clinical presentation in a young girl

The authors report a case of congenital extrahepatic portocaval shunt with a hypoplastic portal vein. This type of shunt is called an Abernethy type 2 shunt, where the portal vein and inferior vena cava are connected side to side, and a hypoplastic portal flow exists in the liver parenchyma. This case of a young girl is complicated with a cardiac anomaly and a large hyperplastic nodule in the liver. This phenotype usually is seen in the Abernethy type 1 shunt, which is a side-to-end shunt with the complete absence of a portal vein. In this context, the current case is very unique in its clinical manifestation, and this phenotype has never been reported. Therefore, it is important to speculate the etiology and treatment of this kind of abnormality and its associated hepatic mass.

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.

Congenital absence of the portal vein associated with focal nodular hyperplasia of the liver and congenital choledochal cyst: a case report

A congenital absence of the portal vein (CAPV) is a rare malformation, which almost is always associated with other anomalies such as hepatic tumors and cardiac malformations. This case report describes a 3-year-old girl with a congenital absence of the portal vein, focal nodular hyperplasia (FNH) of the liver, and a congenital choledochal cyst (CCC). Angiography findings showed the mesenteric vein and splenic vein to be joined together to form a common trunk that entered the inferior vena cava directly above the liver. This is the first known reported case of CAPV with concurrent CCC. J Pediatr Surg 36:622-625.

Oral contraceptive use and focal nodular hyperplasia of the liver

BACKGROUND & AIMS

Because most patients with focal nodular hyperplasia (FNH) are young women, an important decision is whether to discontinue oral contraceptive (OC) use. The aims of this study were to evaluate (1) the number and size of FNH lesions in women with various patterns of OC use and in women without OC use and (2) the modifications in the number and size of FNH lesions during follow-up, according to OC use.

METHODS

In a 9-year study in 216 women with FNH, the diameter and number of lesions documented by magnetic resonance (MR) imaging were evaluated (1) at diagnosis according to OC use as follows: group A, no OC use (n = 28); group B, high-dose OC use (n = 46); group C, low-dose OC use (n = 98); group D, successive use of high-dose and low-dose OCs (n = 33); and group E, use of progestogens only (n = 11); and (2) during follow-up in 136 women, 14 of whom were OC nonusers who stayed off OCs, 89 discontinued OC use, 26 took low-dose OCs, and 7 stayed on a progestogen only. Twelve women became pregnant. In 168 women, the diagnosis of FNH was made based on a combination of rigorously defined MR criteria. In the remaining 48 patients, diagnosis was by surgical biopsy (n = 36) or resection (n = 12). Mean diameter and number of lesion(s) per patient were assessed by MR imaging using the same protocol in all study patients.

RESULTS

No significant differences in the number or size of lesions were found in the 5 patient groups. During follow-up, a change in lesion diameter occurred in only 4 women; this event was not influenced by OC use. In the 12 patients who became pregnant, lesion size was unchanged after delivery, pregnancy was uneventful, and delivery occurred spontaneously.

CONCLUSIONS

These data suggest that (1) neither the size nor the number of FNH lesions are influenced by OC use; (2) size changes during follow-up are rare and do not seem to depend on OC use; and (3) pregnancy is not associated with FNH changes or complications.

Focal nodular hyperplasia: natural course observed with CT and MRI

PURPOSE

The purpose of this work was to assess the natural course of biopsy-proven focal nodular hyperplasia (FNH).

METHOD

Eighteen biopsy-proven FNHs in 14 patients (12 women and 2 men) who were followed for at least 6 months with CT and/or MRI were included in the study. The volume of the lesions was calculated twice by two observers using the summation of areas method. Intra- and interobserver variability was assessed by intraclass correlation coefficients. Longitudinal data analysis was performed with generalized estimating equations.

RESULTS

The volume of FNH was stable in 6 cases, decreased in 10 cases, and increased in 2 cases. Intra- and interobserver variability in size measurements was 5-10%. Intraclass correlation coefficients were >0.992. Longitudinal data analysis showed that there was a general trend of lesion regression.

CONCLUSION

Long-term follow-up and objective measurements performed in patients with biopsy-proven lesions show that the natural course of FNH is variable. In particular, lesion regression is not rare.

A case of progressive multiple focal nodular hyperplasia with alteration of imaging studies

Focal nodular hyperplasia (FNH) of the liver is a lesion characterized by a well circumscribed region of hyperplastic liver tissue with stellate fibrosis. The pathogenesis of the lesion is unknown but various authors consider that FNH may be a response to a preexisting vascular abnormality. We experienced a case of progressive multiple FNH, in which the hemodynamic change as shown by imaging modalities, may support this hypothesis. The patient, a 38-yr-old woman, was found by chance to have multiple portal venous shunts and multiple FNH in both lobes of her liver. Because of their benign characteristics, we followed the nodules periodically without any special treatment. After about 4 yr, the nodules increased both in size and number. In addition, digital subtraction angiography showed that the diameter of the artery had become larger. The hemodynamic change revealed by imaging studies in this case supports the hypothesis that one of the pathogens of FNH is a secondary hepatocellular response to arterial hyperperfusion caused by some vascular malformations.

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.