An algorithm for the accurate identification of benign liver lesions

Focal Nodular Hyperplasia: A Comprehensive Review with a Particular Focus on Pathogenesis and Complications

Focal nodular hyperplasia is a benign tumor of the liver that is often found incidentally with imaging. The purpose of this review is to discuss the pathophysiology, rare complications that can occur due to these lesions, and management options. A literature review was performed on clinical trials and case reports involving focal nodular hyperplasia complications and management of these, as well as the proposed pathogenesis underlying these tumors. Although exposure to oral contraceptive pills and endogenous hormones have been thought to play a role in the development of these lesions, this has not been proven. Most recently, they are thought to arise as a consequence of a vascular anomaly causing alterations in the expression of angiopoietin genes. Complications are rare, but previous cases have reported associated pain, rupture and compression of nearby structures (hepatic vein, stomach, biliary system). Resection of focal nodular hyperplasia is not usually recommended. However, if there is associated pain with no other identifiable cause or presence of a large or growing lesion with risk of causing a complication, then surgical resection, radiofrequency ablation or arterial embolization should be considered.

HYPERVASCULAR LIVER LESIONS IN RADIOLOGICALLY NORMAL LIVER

Background:

The hypervascular liver lesions represent a diagnostic challenge.

Aim:

To identify risk factors for cancer in patients with non-hemangiomatous hypervascular hepatic lesions in radiologically normal liver.

Method:

This prospective study included patients with hypervascular liver lesions in radiologically normal liver. The diagnosis was made by biopsy or was presumed on the basis of radiologic stability in follow-up period of one year. Cirrhosis or patients with typical imaging characteristics of haemangioma were excluded.

Results:

Eighty-eight patients were included. The average age was 42.4. The lesions were unique and were between 2-5 cm in size in most cases. Liver biopsy was performed in approximately 1/3 of cases. The lesions were benign or most likely benign in 81.8%, while cancer was diagnosed in 12.5% of cases. Univariate analysis showed that age >45 years (p< 0.001), personal history of cancer (p=0.020), presence of >3 nodules (p=0.003) and elevated alkaline phosphatase (p=0.013) were significant risk factors for cancer.

Conclusion:

It is safe to observe hypervascular liver lesions in normal liver in patients up to 45 years, normal alanine aminotransaminase, up to three nodules and no personal history of cancer. Lesion biopsies are safe in patients with atypical lesions and define the treatment to be established for most of these patients.

Outcome after a liver resection of benign lesions

BACKGROUND

Benign liver tumours represent a challenge in clinical management. There is considerable controversy with respect to the indications for surgery as the evidence for surgical treatment is variable. The aim of this retrospective study was to analyse the indication and outcome after resection of benign, solid liver lesions.

METHODS

Data of 79 patients, who underwent liver resection between 2001 and 2012, were analysed for demographic and outcome parameters.

RESULTS

Thirty-eight patients with focal nodular hyperplasia (48%), 23 patients with haemangioma (29%) and 18 patients with hepatocellular adenoma (23%) underwent a hepatic resection. A major hepatic resection was performed in 23 patients (29%) and a minor resection in 56 patients (71%). The post-operative mortality rate was zero and the 30-day morbidity rate 13.9%. After a median follow-up of 64 months, 75 patients (95%) were alive, and no patient had developed recurrent disease. Fifty-four patients (68%) were pre-operatively symptomatic, of which, 87% had complete or partial relief of symptoms after a liver resection. The incidence of symptoms increased with the lesions' size.

DISCUSSION

The management of benign liver lesions necessitates an individualized therapy within a multidisciplinary, evidence-based, treatment algorithm. Resection of benign liver lesions can be performed safely in well-selected patients without mortality and low post-operative morbidity.

Immunostaining of glutamine synthetase is a sensitive and specific marker for diagnosing focal nodular hyperplasia in needle biopsy

AIMS

Focal nodular hyperplasia (FNH) has characteristic histological features which may not be seen in needle biopsy specimens. We investigate the diagnostic role of glutamine synthetase (GS) in needle biopsy specimens.

METHODS

Sixty-one hepatic tumours were categorised into 20 'definite' FNHs, 13 'probable' FNHs, and 28 cases without specific diagnosis. Needle biopsy specimens of 92 non-tumourous lesions, 25 well-differentiated hepatocellular carcinomas (WDHCCs), and 4 high-grade dysplastic nodules (HGDNs) and resection specimens of 10 macroregenerative nodules were also selected for immunohistochemical stain of GS for comparison.

RESULTS

All 20 'definite' FNHs, nine 'probable' FNHs, and five cases without specific diagnosis expressed typical map-like staining pattern of GS. The demographic data of these five cases were similar to those of FNH. All cases of chronic hepatitis B and C, cirrhosis, macroregenerative nodule and peritumourous liver tissue showed normal pericentral/periseptal pattern. Fifteen of 25 WDHCCs and one HGDN showed diffuse pattern. Ten WDHCCs and two HGDNs showed negative staining. One HGDN showed mosaic pattern.

CONCLUSIONS

Immunohistochemical staining of GS increases the diagnostic sensitivity of FNH in needle biopsy, especially in those without typical morphology. It also helps in differentiating FNH from other tumourous and non-tumourous lesions.

Impact on liver cancer treatment of a first erroneous diagnosis of hemangioma

BACKGROUND

Most liver hemangioma (HA) diagnoses are presumptive and based on radiological features and growth trend. The goal of this study was to analyze the impact of a false diagnosis of hemangioma upon the overall therapeutic course and upon the prognosis of a liver malignancy.

METHODS

Twenty-eight patients with liver cancer who were observed in the period 2001-2007 after an initial erroneous diagnosis of HA were retrospectively evaluated. We studied their radiological workup after blind revision of the images by two radiologists with specific expertise in liver imaging, analyzing the relationship between overall management and center volume, mean delay from the first test to the curative treatment, and clinical consequences of this diagnostic mistake.

RESULTS

The diagnosis of false HA occurred in a low-volume center (LVC) in 75 % of cases. A specific risk for liver cancer was present in 71.4 % of patients. US gave a false diagnosis of HA in 25/27 patients, a CT scan in 18/25 patients, and MRI in 6/16 patients. The final diagnosis was reached with a mean delay of 22 months. Liver resection was possible in 22 patients; in the 17 hepatocellular carcinoma cases, the survival rate was 69.4 % at 5 years after the first observation.

CONCLUSIONS

A false diagnosis of HA in the presence of malignancy is not rare nowadays and significantly reduces the chances of cure. In situations at risk of having the error occur (poor technical quality of imaging, low specific experience, doubtful diagnosis, and high-cancer-risk patient), the rationale approach is to discuss the case with a multidisciplinary team skilled in the field of liver cancer.

Has laparoscopy increased surgical indications for benign tumors of the liver?

BACKGROUND

We aimed to analyze the risk of an increased surgical indication rate in patients with benign tumors of the liver since the development of laparoscopy. Previous articles have reported increased numbers of laparoscopic procedures in different surgical fields.

METHODS

A literature search of MEDLINE (PubMed), Google Scholar, and The Cochrane Library was carried out. All articles that analyzed benign liver tumors (hemangiomas, focal nodular hyperplasia, and adenoma) were divided in two groups: group I included all manuscripts with open procedures between 1971 at 1990, and group II included all manuscripts with open or laparoscopic procedures between 1991 and 2010. Group II articles were divided into two subgroups. Subgroup IIA patients were treated by open or laparoscopic procedures between 1991 and 2000, and subgroup IIB patients were treated by open or laparoscopic procedures between 2001 and 2010.

RESULTS

Specific analysis of each kind of tumor observed in the two groups showed fewer surgically treated patients for hepatic hemangioma and hepatic adenoma in group II compared with group I and a greater number of patients for focal nodular hyperplasia. Fewer patients were treated with laparoscopic procedures in subgroup IIA than in subgroup IIB. A chi-square test with Yates' correction gave a P value of <0.001.

CONCLUSION

Laparoscopy has increased the rate of hepatic resection for benign tumors with doubtful indications.

Clinical utility of acoustic radiation force impulse imaging for identification of malignant liver lesions: a meta-analysis

OBJECTIVES

To assess the performance of acoustic radiation force impulse (ARFI) imaging for identification of malignant liver lesions using meta-analysis.

METHODS

PubMed, the Cochrane Library, the ISI Web of Knowledge and the China National Knowledge Infrastructure were searched. The studies published in English or Chinese relating to evaluation accuracy of ARFI imaging for identification of malignant liver lesions were collected. A hierarchical summary receiver operating characteristic (HSROC) curve was used to examine the ARFI imaging accuracy. Clinical utility of ARFI imaging for identification of malignant liver lesions was evaluated by Fagan plot analysis.

RESULTS

A total of eight studies which included 590 liver lesions were analysed. The summary sensitivity and specificity for identification of malignant liver lesions were 0.86 (95 % confidence interval (CI) 0.74-0.93) and 0.89 (95 % CI 0.81-0.94), respectively. The HSROC was 0.94 (95 % CI 0.91-0.96). After ARFI imaging results over the cut-off value for malignant liver lesions ("positive" result), the corresponding post-test probability for the presence (if pre-test probability was 50 %) was 89 %; in "negative" measurement, the post-test probability was 13 %.

CONCLUSIONS

ARFI imaging has a high accuracy in the classification of liver lesions.

KEY POINTS

Acoustic radiation force impulse (ARFI) imaging is a novel ultrasound-based elastography method. This study comprehensively assessed the published performance of ARFI for liver lesions. ARFI imaging appears to have high sensitivity and specificity for liver lesions. ARFI can help differentiate liver lesions and may prevent unnecessary biopsies.

Malignant transformation of hepatocellular adenomas into hepatocellular carcinomas: a systematic review including more than 1600 adenoma cases

BACKGROUND

Malignant transformation of hepatocellular adenomas (HCAs) into hepatocellular carcinomas (HCCs) has been reported repeatedly and is considered to be one of the main reasons for surgical treatment. However, its actual risk is currently unknown.

OBJECTIVE

To provide an estimation of the frequency of malignant transformation of HCAs and to discuss its clinical implications.

METHODS

A systematic literature search was conducted using the following databases: The Cochrane Hepatobiliary Group Controlled Trials Register, The Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, MEDLINE and EMBASE.

RESULTS

One hundred and fifty-seven relevant series and 17 case reports (a total of 1635 HCAs) were retrieved, reporting an overall frequency of malignant transformation of 4.2%. Only three cases (4.4%) of malignant alteration were reported in a tumour smaller than 5 cm in diameter.

DISCUSSION

Malignant transformation of HCAs into HCCs remains a rare phenomenon with a reported frequency of 4.2%. A better selection of exactly those patients presenting with an HCA with an amplified risk of malignant degeneration is advocated in order to reduce the number of liver resections and thus reducing the operative risk for these predominantly young patients. The Bordeaux adenoma tumour markers are a promising method of identifying these high-risk adenomas.

Gadoxetate disodium-enhanced MRI of the liver: part 1, protocol optimization and lesion appearance in the noncirrhotic liver

OBJECTIVE

The purpose of this article is to review the pharmacokinetic and pharmacodynamic properties of gadoxetate disodium (Gd-EOB-DTPA), to describe a workflow-optimized pulse sequence protocol, and to illustrate the imaging appearance of focal lesions in the noncirrhotic liver.

CONCLUSION

Gd-EOB-DTPA allows a comprehensive evaluation of the liver with the acquisition of both dynamic and hepatocyte phase images. This provides potential additional information, especially for the detection and characterization of small liver lesions. However, protocol optimization is necessary for improved image quality and workflow.

Surgical management of hepatocellular adenoma: take it or leave it?

BACKGROUND

Hepatocellular adenoma (HA) is a rare benign tumor of the liver. Surgical resection is generally indicated to reduce risks of hemorrhage and malignant transformation. We sought to evaluate clinical presentation, surgical management, and outcomes of patients with HA at our institution.

METHODS

We performed a retrospective review of 41 patients who underwent surgical resection for HA between 1988 and 2007.

RESULTS

Thirty-eight patients were women, and the median age at presentation was 36 years (range, 19-65 years). The most common clinical presentation was abdominal pain (70%) followed by incidental radiological finding (17%). Twenty-two patients had a history of oral contraceptive use. Median number of HA was one (range, 1-3). There were 32 open cases (3 trisectionectomy, 15 hemihepatectomy, 7 sectionectomy, 4 segmentectomy, and 3 wedge resection), and 9 laparoscopic cases (1 hemihepatectomy, 5 sectionectomy, 1 segmentectomy, and 2 wedge resection). The median estimated blood loss was 225 mL (range, 0-3400 mL). The median length of stay was 6 days (range, 1-15 days). Surgical morbidities included pleural effusion requiring percutaneous drainage (n = 2), pneumonia (n = 1), and wound infection (n = 1). There was no perioperative mortality. Twelve patients had hemorrhage from HA. Hepatocellular carcinoma was observed in two patients with HA. Median follow-up was 23 months (range, 1-194 months), at which time all patients were alive.

CONCLUSION

In view of 29% hemorrhagic and 5% malignant complication rates, we recommend surgical resection over observation if patient comorbidities and anatomic location of HA are favorable. A laparoscopic approach can be safely used in selected cases.

[Incidentalomas of the liver and gallbladder. Evaluation and therapeutic procedure]

The expanding use of ultrasound in general practice is leading to an ever increasing rate of detection of true hepatic incidentaloma. The correct diagnosis of hepatic incidentaloma may be made in over 90% with non-invasive means. The questionable diagnosis of "symptomatic" incidentaloma should undergo close scrutiny prior to a decision in favour of surgery. With regard to more recent literature, the former "absolute" requirement for surgical resection in all cases of liver cell adenoma may have to be reappraised. Final inability to rule out malignancy represents an unquestionable indication for surgery in the light of low rates of morbidity and lack of mortality in this otherwise healthy patient group. Percutaneous biopsies should not be performed due to oncological hazards, indeterminate results and potential for acute complications.The stage-oriented radical re-resection following diagnosis of an incidentally detected gallbladder cancer may lead to significantly improved long-term survival, especially in the early tumour stages T1b and T2, which represents the most common stage of gallbladder cancer in incidentaloma. Patients at elevated risk for incidental gallbladder cancer should undergo thorough instruction with regard to the potential hazards of laparoscopic cholecystectomy. Multimodal therapeutic strategies directed at advanced stages of incidentally detected gallbladder cancer should be evaluated in prospective multicentre studies.

Manejo terapéutico de la hemorragia espontánea hepática debido a una hiperplasia nodular focal

Focal nodular hyperplasia is a benign liver tumor that usually follows an asymptomatic course. Hemorrhage of hepatic focal nodular hyperplasia is exceptional and occurs in tumors such as hepatocellular carcinoma and hepatic adenoma. We report the case of a woman with spontaneous rupture and hemorrhage of focal nodular hyperplasia. Hemodynamic stabilization was achieved by selective hepatic arterial embolization. Elective hepatic resection was subsequently performed. This clinical course is extremely rare. We describe the therapeutic management of these complications using hepatic transarterial embolization, which could avoid potentially harmful aggressive treatments.

Elective surgery for benign liver tumours

BACKGROUND

Benign liver tumours (haemangioma, focal nodular hyperplasia, and hepatic adenoma) have different prevalence and prognosis. Spontaneous rupture and malignant transformation can complicate hepatic adenoma. Elective surgery is controversial, and indications are represented by uncertain diagnosis, presence of symptoms, and prevention of major complications.

OBJECTIVES

To assess the beneficial and harmful effects of elective surgery of benign liver tumours. We identified 31 cases series. These were small (with less than 60 participants) and the types of tumours mixed. These studies reported no significant mortality, but in the six studies with mortality it ranged from 1% to 17%.

SEARCH STRATEGY

The Cochrane Hepato-Biliary Group Controlled Trials Register and the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (searches in Issue 1, 2006), MEDLINE, EMBASE, CancerLit, and Science Citation Index Expanded (SCI-EXPANDED) (searched December 2005). A further search included the proceedings of major hepatological and surgical congresses (Annual Meetings of the American Association for the Study of the Liver (AASLD) and European Association for the Study of the Liver (EASL)), and examination of the references of relevant papers and reference lists of the identified studies.

SELECTION CRITERIA

Randomised clinical trials in adult patients with benign liver tumours without indications for emergency surgery in which elective surgery (resection) versus no intervention or sham operation are compared.

DATA COLLECTION AND ANALYSIS

All trials identified through searches were evaluated for eligibility for inclusion. We intended to extract relevant data in order to analyse the outcomes as per our published protocol using intention-to-treat analysis.

MAIN RESULTS

We could not identify any randomised clinical trials.

AUTHORS' CONCLUSIONS

We were unable to find evidence supporting or refuting elective surgery for patients with benign liver tumours. We need large, long-term randomised clinical trials with adequate methodology to assess the benefits and harms of elective surgery.

Impact of intraoperative ultrasonography in laparoscopic liver surgery

BACKGROUND

Laparoscopic surgery has gained growing acceptance, but this does not hold for laparoscopic surgery of the liver. This mainly includes diagnostic procedures, interstitial therapies, and treatment of liver cysts. However, the authors believe there is room for a laparoscopic approach to the liver in selected cases.

METHODS

A prospective study of laparoscopic liver resections was undertaken with patients who had preoperative diagnoses of benign lesion and hepatocellular carcinoma with compensated cirrhosis. The inclusion criteria required that hepatic involvement be limited and located in the left or peripheral right segments (segments 2-6), and that the tumor be 5 cm or smaller. The location of the tumor and its transection margin were defined by laparoscopic ultrasound (LUS).

RESULTS

From December 1996, 17 (5%) of 313 liver resections were included in the study. There were 5 benign lesions and 12 hepatocellular carcinomas in cirrhotic patients. The mean age of the study patients was 59 years (range, 29-79 years). The LUS evaluation identified the presence of new hepatocellular carcinoma nodules in two patients (17%). The resections included 1 bisegmentectomy, 8 segmentectomies, 3 subsegmentectomies, and 3 nonanatomic resections. The mean operative time, including laparoscopic ultrasonography, was 156 +/- 50 min (median, 150 min; range, 60-250 min), and the perioperative blood loss was 190 +/- 97 ml. There was no mortality. Conversion to laparotomy was necessary for two patients. Postoperative complications were experienced by 3 of 15 patients, all of them cirrhotics. One of the patients had a wall hematoma, and the remaining two patients had bleeding from a trocar access requiring a laparoscopic reexploration. The mean hospital stay for the whole series was 6.9 +/- 4.9 days (median, 6 days; range, 2-25 days) and 5.6 +/-1.4 days (median, 6 days; range, 2-8 days) for the 15 laparoscopic patients.

CONCLUSION

Laparoscopic treatment should be considered for selected patients with benign and malignant lesions in the left lobe or frontal segments of the liver. Evaluation by LUS is indispensable to guarantee precise determination of the segmental tumor location and the relationship of the tumor to adjacent vascular or biliary structures, excluding adjacent or adjunctive new lesions. The evolution of laparoscopic hepatectomies probably will depend on the development of new techniques and instrumentations.

Case-orientated approach to the management of hepatocellular adenoma

Background

Treatment of suspected hepatocellular adenoma (HA) remains controversial. The aim of this study was to evaluate the management of HA at a time when magnetic resonance imaging (MRI) and computed tomography (CT) are highly sensitive methods for diagnosing HA.

Methods

Between January 2000 and January 2005, data from 48 consecutive women with HA (median age 36 years) were prospectively collected. The protocol for diagnostic work-up consisted of multiphasic MRI or CT. Management was observation if the tumour was smaller than 5 cm and surgical intervention if it was 5 cm or larger.

Results

The median follow-up was 24 (range 3–73) months. Sixteen (33 per cent) patients had invasive procedures because of tumour size 5 cm or larger, malignant characteristics or haemorrhage. The remaining 32 patients (67 per cent) were observed; haemorrhage and malignant degeneration did not occur and none of the lesions showed enlargement after withdrawal of oral contraceptives. Multiple HAs were found in 32 (67 per cent) patients; liver steatosis was significantly more common in these patients than in those with a solitary lesion (59 versus 19 per cent; P = 0·008).

Conclusion

Observation of adenomas smaller than 5 cm is justified because of improved radiological reliability. Resection should be reserved for patients with malignant tumour characteristics or with single lesions 5 cm or larger.

Giant hepatic adenoma with bone marrow metaplasia not associated with oral contraceptive intake

BACKGROUND

Hepatocellular adenomas are the most common benign liver tumors. They are usually related to oral contraceptive intake.

CASE PRESENTATION

This case describes a 58-year-old woman admitted to our institution for a hepatic mass incidentally discovered during a routine examination. The patient, who was never on oral contraceptives, was asymptomatic upon admission. She underwent a thorough diagnostic evaluation and then a hepatic right trisegmentectomy. The histologic evaluation of the mass showed that it was a hepatocellular adenoma with areas of bone marrow metaplasia.

CONCLUSION

Bone marrow metaplasia has rarely been found associated to liver tumors. The presence of marrow-derived hepatic progenitor cells might be the source of both adenoma hepatocytes and bone marrow differentiated cells. To our knowledge, this is only the second case in the English literature in which areas of bone marrow metaplasia were found in a hepatocellular adenoma.

Focal Nodular Hyperplasia (FNH): A Potential Cause of False-Positive Positron Emission Tomography

Positron emission tomography (PET) using F-18 fluorodeoxyglucose (FDG) has been proven to be a useful tool in the differential diagnosis of liver tumors. Focal nodular hyperplasia (FNH) is an uncommon benign liver lesion, which can be difficult to differentiate from other benign and malignant liver pathologies. FDG PET imaging usually shows uptake similar or even decreased compared to that of the normal liver. We describe a hypermetabolic FNH lesion in a patient with a history of breast cancer. Computed tomography scan, ultrasonography (US), and magnetic resonance imaging were negative. The lesion was resected, and histologic findings were consistent with FNH.

The diagnosis and management of benign hepatic tumors

Benign hepatic tumors include a broad spectrum of regenerative and true neoplastic processes. Because of advances in imaging studies such as computed tomography (CT) and magnetic resonance imaging (MRI) as well as progress in immunohistochemistry, accurate diagnosis can now be made in a large percentage of patients without surgical laparotomy or resection. This article will focus on the pathogenesis, diagnosis, and management of focal benign lesions of the liver. Many of these tumors present with typical features in various imaging studies. On occasions, biopsies are required and/or surgical removal is needed. The most common benign hepatic tumors include cavernous hemangioma, focal nodular hyperplasia, hepatic adenoma, and nodular regenerative hyperplasia. In the majority of cases of benign hepatic tumors, patients are asymptomatic, and no treatment is indicated. The main indication for treatment is the presence of significant clinical symptoms or suspicion of malignancy or fear of malignant transformation.

Multiple focal nodular hyperplasia of the liver in a 21-year-old woman

Focal nodular hyperplasia (FNH) is a relatively common condition, the diagnosis of which is now regularly made with diagnostic imaging. Cases of multiple FNH (more than four lesions) are rare, however, and the presence of numerous lesions may complicate the workup and diagnosis. We recently treated a young woman with multiple FNH. We report this case to highlight the clinical issues presented by this rare variant of a common benign hepatic disease.