Management of Benign Hepatic Tumors

[Benign solid liver tumors]

Benign solid liver tumors are frequently discovered during routine sonographic examinations. As a rule, malignant tumors can be excluded using contrast medium-based sectional imaging; however, unclear cases can represent a diagnostic challenge. The category of solid benign liver tumors includes first and foremost hepatocellular adenoma (HCA), focal nodular hyperplasia (FNH) and hemangioma. Based on the most recent data, an overview of the current standards in the diagnostics and treatment is given.

Surgical Management of Hepatic Benign Disease: Have the Number of Liver Resections Increased in the Era of Minimally Invasive Approach? Analysis from the I Go MILS (Italian Group of Minimally Invasive Liver Surgery) Registry

BACKGROUND

Increased expertise with minimally invasive liver surgery (MILS) could cause an unjustified extension of indications to resect liver benign disease (BD). The aim of this study was to evaluate the operative risk of MILS for BD and if implementation and diffusion of MILS have widened indications for BD resection.

METHODS

A prospective study including centers with > 6 MILS for BD, enrolled in the I Go MILS registry from January 2015 to October 2016. Cysts fenestrations were excluded.

RESULTS

Eight hundred eighteen MILS were performed in 15 centers. One hundred seventy-three of these (21.1%) were for BD: conversion rate was 6.9%, postoperative mortality and morbidity rates were 0 and 13.9%. During the same period, 3713 liver resections (open + MILS) were performed and 407 (11.0%) were for BD. A time-trend analysis showed that the total number of MILS and the number of MILS for malignant disease significantly increased, but this increasing trend was not documented for the number of MILS for BD, which remained stable during the study period of time. This trend was confirmed for the overall rate of resected BD (open + MILS) that remained stable.

DISCUSSION

BD represents a valid indication for MILS. For BD, 21.1% of MILS was performed, rate significantly lower than that previously reported in Italy. Although an evident growth of the use of MILS was observed during the time period analysis in Italy, this trend did not correspond to an increased number of MILS for BD, and the overall rate of resected BD was comparable to that reported in previous large open series.

MRI characterization of focal liver lesions in non-cirrhotic patients: assessment of added value of gadoxetic acid-enhanced hepatobiliary phase imaging

Background

To evaluate the added value of the hepatobiliary (HPB) phase in gadoxetic acid-enhanced magnetic resonance imaging (MRI) in characterizing newly discovered indeterminate focal liver lesions in non-cirrhotic patients.

Results

One-hundred and twenty-five non-cirrhotic patients (median age, 46 years; range, 20–85 years; 100 females) underwent gadoxetic acid-enhanced MRI, including the 20-min delayed HPB phase, for characterization of newly discovered focal liver lesions. Images were independently evaluated by two blinded, board-certified abdominal radiologists (R1 and R2) who characterized liver lesions without and with assessment of the HPB phase images in two separate readout sessions. Confidence in diagnosis was scored on a scale from 0 to 3. Inter-observer agreement was assessed using Cohen κ statistics. Change in diagnosis and confidence in diagnosis were evaluated by Wilcoxon signed rank test. There was no significant change in diagnosis before and after evaluation of the HPB phase for both readers (p = 1.0 for R1; p = 0.34 for R2). Confidence in diagnosis decreased from average 2.8 ± 0.45 to 2.6 ± 0.59 for R1 and increased from 2.6 ± 0.83 to 2.8 ± 0.46 for R2. Change in confidence was only statistically significant for R1 (p = 0.003) but not significant for R2 (p = 0.49). Inter-reader agreement in diagnosis was good without (k = 0.66) and with (k = 0.75) inclusion of the HPB phase images.

Conclusions

The added information obtained from the HPB phase of gadoxetic acid-enhanced MRI does not change the diagnosis or increase confidence in diagnosis when evaluating new indeterminate focal liver lesions in non-cirrhotic patients.

Hepatocellular carcinoma arising from hepatic adenoma in a young woman

Hepatocellular carcinoma (HCC) arising from hepatic adenoma is an infrequent situation. Only a few cases were reported in the literature. We present a rare case of hepatocellular carcinoma arising from HA in a young woman with no medication history of oral contraceptives. Surgical resection is the only available treatment.

Spontaneous hepatic haemorrhage secondary to ruptured hepatocellular adenoma in a young male patient

A 27-year-old man presented with acute right upper quadrant abdominal pain and vomiting. He was clinically in hypovolaemic shock. Investigations revealed normocytic anaemia with a normal bilirubin and moderate liver function test abnormalities. CT abdomen and pelvis demonstrated haemoperitoneum and a large solitary hepatic mass in segments V and VI, suspicious for a ruptured hepatic tumour. Massive transfusion protocol was commenced and angioembolisation of the inferior branch of the right hepatic artery was undertaken. Despite this, his haemorrhagic shock was resistant to resuscitation. Thus, he underwent emergent exploratory laparotomy, which resulted in segments V and VI liver resection and packing. Re-look laparotomy 2 days following initial exploration was performed where haemostasis was confirmed. Histopathology revealed a ruptured well-differentiated hepatocellular adenoma. The patient made a good recovery following a 2-week admission.

Malignant degeneration of hepatic adenomas to hepatocellular carcinoma

Background Hepatic adenomas (HA) are rare, benign proliferations of hepatocytes with high glycogen and fat content that lack normal hepatic architecture. In general, the long-term incidence of malignant degeneration to HCC has not been well characterized. This case report discusses a 37 male with a 10-year history of weekly anabolic steroid abuse who presented with bilobar hepatic adenomas with subsequent malignant degeneration to hepatocellular carcinoma (HCC). Case Presentation Our patient is a 37 old male with a 10-year history of weekly anabolic steroid abuse who presented to his primary care physician (PCP) in July 2013 with intermittent right upper quadrant (RUQ) pain. He was subsequently referred to our cancer center after abdomen/pelvis computed tomography (CT A/P) with oral and intravenous (IV) contrast at an outside hospital revealed two large hepatic masses. The larger mass in segment 2 measured 6.5 x 9.1 cm, while the segment 6/7 mass measured 7.5 x 7.6 cm. Abdomen magnetic resonance imaging (MRI) with and without IV contrast performed at our institution on July 23, 2013 confirmed the presence of the two above noted masses, which were felt to be consistent with probable HA, although HCC could not be definitely ruled out. Of note, his carcinoembryonic antigen (CEA) and alpha-fetoprotein (AFP) were within normal limits. Percutaneous, ultrasound-guided (US) biopsy of the left lobe mass was consistent with probable HA, although HCC could not be definitely ruled out. Conclusion We present the case of a 37-year-old male 10-year history of weekly anabolic steroid abuse who presented to us in 2013 with HA which had malignant degeneration to HCC while on surveillance over a 2-year period. This case report stresses the importance of having a high clinical suspicion for HA in patients with a history of anabolic steroid abuse and liver masses. Additionally, it reiterates that it can be difficult to differentiate HA from well-differentiated HCC on imaging and/or with a limited biopsy. Furthermore, it is important to keep in mind that the growth of a mass, especially off steroids is highly concerning for malignancy (and masses that fail to regress completely can harbor occult HCC).

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.

Screening the key genes of hepatocellular adenoma via microarray analysis of DNA expression and methylation profiles

The aim of the present study was to identify the biomarkers involved in the development of hepatocellular adenoma (HCA) through integrated analysis of gene expression and methylation microarray. The microarray dataset GSE7473, containing HNF1α-mutated HCA and their corresponding non-tumor livers, 5 HNF1α-mutated HCA and 4 non-related non-tumor livers, was downloaded from the Gene Expression Omnibus (GEO) database. The DNA methylation profile GSE43091, consisting of 50 HCA and 4 normal liver tissues, was also downloaded from the GEO database. Differentially expressed genes (DEGs) were identified by the limma package of R. A t-test was conducted on the differentially methylated sites. Functional enrichment analysis of DEGs was performed through the Database for Annotation, Visualization and Integrated Analysis. The genes corresponding to the differentially methylated sites were obtained by the annotation files of methylation chip platform. A total of 182 DEGs and 3,902 differentially methylated sites were identified in HCA. In addition, 238 enriched GO terms, including organic acid metabolic process and carboxylic acid metabolic process, and 14 KEGG pathways, including chemical carcinogenesis, were identified. Furthermore, 12 DEGs were identified to contain differentially methylated sites, among which, 8 overlapped genes, including pregnancy zone protein and solute carrier family 22 member 1 (SLC22A1), exhibited inverse associations between gene expression levels and DNA methylation levels. The DNA methylation levels may be potential targets of HCA. The present study revealed that the 8 overlapped genes, including annexin A2, chitinase 3-like 1, fibroblast growth factor receptor 4, mal, T-cell differentiation protein like, palladin, cytoskeletal associated protein, plasmalemma vesicle associated protein and SLC22A1, may be potential therapeutic targets of HCA.

Malignant transformation of hepatocellular adenoma with bone marrow metaplasia arising in glycogen storage disease type I: A case report

Malignant transformation of hepatocellular adenoma (HA) is relatively rare and has been reported to be associated with dysregulation of the β-catenin pathway. The presence of bone marrow metaplasia in HA is an uncommon histological characteristic. The current report presents the case of a 46-year-old woman with glycogen storage disease type I (von Gierke's disease) who underwent resection of hepatocellular carcinoma (HCC) arising in a HA with associated bone marrow metaplasia producing three series of hematopoietic cells. The serum level of proteins induced by des-gamma-carboxy prothrombin (DCP) gradually increased as the tumors grew; following hepatic resection, DCP levels returned to normal. Nuclear accumulation of β-catenin was shown in HCC by immunohistochemistry; however, no mutation was detected in exon 3 of β-catenin. To the best of our knowledge, this is the first report of HA with absolute bone marrow metaplasia producing three series of hematopoietic cells. This occurrence suggests that elevated DCP may be an indicator of malignant transformation of HA.

Preoperative arterial embolization of large liver hemangiomas

PURPOSE

We aimed to investigate the efficacy and safety of preoperative selective intra-arterial embolization (PSIAE) in the surgical treatment of large liver hemangiomas.

METHODS

Data of 22 patients who underwent resection of large liver hemangiomas were retrospectively analyzed. PSIAE was performed in cases having a high risk of severe blood loss during surgery (n=11), while it was not applied in cases with a low risk of blood loss (n=11).

RESULTS

A total of 19 enucleations and six anatomic resections were performed. Operative time, intraoperative bleeding amount, Pringle period, and blood transfusion were comparable between the two groups (P > 0.05, for all). The perioperative serum aspartate transaminase level was not different between groups (P = 1.000). Perioperative total bilirubin levels were significantly increased in the PSIAE group (P = 0.041). Postoperative hospital stay was longer in the PSIAE group. Surgical complications were comparable between groups (P = 0.476).

CONCLUSION

Patients who underwent PSIAE due to a high risk of severe blood loss during resection of large liver hemangiomas had comparable operative success as patients with a low risk of blood loss who were operated without PSIAE. Hence, PSIAE can be used for the control of intraoperative blood loss, especially in surgically difficult cases.

The value of liver resection for focal nodular hyperplasia: resection yes or no?

Background

Focal nodular hyperplasia (FNH) are benign lesions in the liver. Although liver resection is generally not indicated in these patients, rare indications for surgical approaches indeed exist. We here report on our single-center experience with patients undergoing liver resection for FNH, focussing on preoperative diagnostic algorithms and quality of life (QoL) after surgery.

Methods

Medical records of 100 consecutive patients undergoing liver resection for FNH between 1992 and 2012 were retrospectively analyzed with regard to diagnostic pathways and indications for surgery. Quality of life (QoL) before and after surgery was evaluated using validated assessment tools. Student’s t test, one-way ANOVA, χ², and binary logistic regression analyses such as Wilcoxon–Mann–Whitney test were used, as indicated.

Results

A combination of at least two preoperative diagnostic imaging approaches was applied in 99 cases, of which 70 patients were subjected to further imaging or tumor biopsy. In most patients, there was more than one indication for liver resection, including tumor-associated symptoms with abdominal discomfort (n = 46, 40.7 %), balance of risk for malignancy/history of cancer (n = 54, 47.8 %/n = 18; 33.3 %), tumor enlargement/jaundice of vascular and biliary structures (n = 13, 11.5 %), such as incidental findings during elective operation (n = 1, 0.9 %). Postoperative morbidity was 19 %, with serious complications (>grade 2, Clavien–Dindo classification) being evident in 8 %. Perioperative mortality was 0 %. Liver resection was associated with a significant overall improvement in general health (very good–excellent: preoperatively 47.4 % vs. postoperatively 68.1 %; p = 0.015).

Conclusions

Liver resection remains a valuable therapeutic option in the treatment of either symptomatic FNH or if malignancy cannot finally be ruled out. If clinically indicated, liver resection for FNH represents a safe approach and may lead to significant improvements of QoL especially in symptomatic patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s40001-015-0181-x) contains supplementary material, which is available to authorized users.

Focal nodular hyperplasia and hepatocellular adenoma: The value of shear wave elastography for differential diagnosis

OBJECTIVE

This study assessed the clinical usefulness of shear wave elastography (SWE) during ultrasound for differentiating between focal nodular hyperplasias (FNHs) and hepatocellular adenomas (HAs).

MATERIALS AND METHODS

SWE was performed on 56 patients presenting with 76 liver lesions (57 FNHs and 19HAs) that were confirmed by MRI and contrast-enhanced ultrasound (CEUS) (n=55) or by histology (n=21). A mean elasticity value was obtained for each lesion. The ratios of the elasticity of the lesions to the elasticity of the surrounding liver were determined. The optimal elasticity cut-off value for distinguishing between the two lesion types was determined using ROC analysis. All lesions that were classified as "undetermined" after CEUS were reclassified using the elasticity values.

RESULTS

The mean elasticity value was 46.99 ± 31.15 kPa for FNHs and 12.08 ± 10.68 kPa for HAs (p<0.0001). The mean relative elasticity ratio values were 7.94 ± 6.43 and 1.91 ± 1.70, respectively (p<0.0001). The ROC analysis showed a maximal accuracy of 95% for identification with a cut-off of 18.8 kPa for lesion elasticity (accuracy of 96% with a cut-off of 1.98 for the relative elasticity ratio). A total of 68 CEUS were performed, and 17 lesions (25%) were classified as "undetermined" after CEUS. With these cut-off values 16 lesions (94.1%) were correctly reclassified as FNHs.

CONCLUSION

SWE is a useful adjunctive tool for differentiation between FNH and HA during ultrasound examination.

Minimally invasive liver surgery in a hepato-biliary unit: learning curve and indications

Operative indications and type of resection represent a crucial issue of minimally invasive liver surgery (MILS), and they should not be modified by the increased experience of laparoscopic liver surgeons. The aim of this study was to define the indications for MILS and the learning curve in a high-volume hepatobiliary surgery Unit. Between 2009 and 2014, 993 liver resections were performed in our unit, and MILS was performed in 81 of these (8.2%). The proportion of MILS significantly increased over the study period of time and was significantly higher during the last 2 years than during the first 2 years (10.8 vs. 6.4%; p = 0.042). Rate of liver resections for benign disease between the first 2 years and the last 2 years of the study period was not significantly different (14.7 vs. 10.5%; p = 0.098). Rate of MILS for malignant disease significantly increased from the first 2 years to the last 2 years: 3.2 vs. 7.5% (p < 0.001). Indication for left lateral sectionectomy in the whole series was rare. It was performed in 37 cases as the only liver surgical procedure, on 993 liver resections (3.7%). In 25 (67.6%) of these, a minimally invasive approach was used. Rate of left lateral sectionectomies between the first 2 years and the last 2 years of the study period was not significantly different: 4.5 vs. 3.8% (p = 0.645). This study shows that the proportion of MILS significantly increased over the study period of time in our high-volume hepatobiliary surgery Unit without changing surgical indications for benign disease and type of resections.

MR imaging features for improved diagnosis of hepatocellular carcinoma in the non-cirrhotic liver: Multi-center evaluation

PURPOSE

To determine MR-imaging features for the differentiation between hepatocellular carcinoma (HCC) and benign hepatocellular tumors in the non-cirrhotic liver.

MATERIAL AND METHODS

107 consecutive patients without liver cirrhosis (46 male; 45 ± 14 years) who underwent liver resection due to suspicion of HCC were included in this multi-center study. The following imaging features were assessed: lesion diameter and demarcation, satellite-lesions, central-scar, capsule, fat-content, hemorrhage, vein-infiltration and signal-intensity (SI) on native T1-, T2- and dynamic-enhanced T1-weighted images (center versus periphery). In addition, contrast-media (CM) uptake in the liver specific phase was analyzed in a sub-group of 42 patients.

RESULTS

Significant differences between HCC (n=55) and benign lesions (n=52) were shown for native T1-, T2- and dynamic-enhanced T1-SI, fat-content, and satellite-lesions (all, P<.05). Independent predictors for HCC were T1-hypointensity (odds-ratio, 4.81), T2-hypo-/hyperintensity (5.07), lack of central tumor-enhancement (3.36), and satellite-lesions (5.78; all P<0.05). Sensitivity and specificity of HCC was 91% and 75% respectively for two out-of four independent predictors, whereas specificity reached 98% for all four predictors. Sub-analysis, showed significant differences in liver specific CM uptake between HCC (n=18) and benign lesions (n=24; P<0.001) and revealed lack of liver specific CM uptake (odds-ratio, 2.7) as additional independent feature for diagnosis of HCC.

CONCLUSION

Independent MRI features indicating HCC are T1-hypointensity, T2-hypo- or hyperintensity, lack of central tumor-enhancement, presence of satellite-lesions and lack of liver specific CM-uptake. These features may have the potential to improve the diagnosis of HCC in the non-cirrhotic liver.

Management of Hepatocellular Adenoma: Recent Advances

Hepatocellular adenoma (HCA) is a rare benign liver cell neoplasm that occurs more frequently in young women with a history of prolonged use of oral contraceptives. Surgical resection is considered because of the risk of hemorrhage in 25% and of malignant transformation in 5% of patients with HCA. HCA is a heterogeneous disease comprising 3 subtypes with distinct molecular and complication profiles. The inflammatory or telangiectatic subtype is at increased risk for hemorrhage, the β-catenin-activated subtype is at increased risk for malignant transformation, and the hepatocyte nuclear factor-1α-inactivated or steatotic subtype is at the least risk for complications. One-third of the patients with HCA have multiple tumors on imaging with no increased risk of complications. Magnetic resonance imaging is the modality of choice for the diagnosis and subtype characterization of HCA. Systematic resection of HCA is recommended in male patients owing to the higher incidence of malignant transformation, and surgical excision in women should be reserved for tumors 5 cm or larger associated with an increased risk of complications. Cessation of hormonal therapy and radiologic surveillance in women with HCA tumors smaller than 5 cm shows that the vast majority of HCA remain stable or undergo spontaneous regression. Percutaneous core needle biopsy is of limited value because the therapeutic strategy is based primarily on patient sex and tumor size. Transarterial embolization is the initial treatment for HCA complicated by hemorrhage. Pregnancy should not be discouraged in the presence of HCA, however, frequent sonographic surveillance is recommended.

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.

Update on the new classification of hepatic adenomas: clinical, molecular, and pathologic characteristics

CONTEXT

Hepatic adenoma is an uncommon, benign, hepatic neoplasm that typically occurs in women of child-bearing age, often with a history of long-term use of oral contraceptive drugs. This is usually detected as an incidental mass lesion in a noncirrhotic liver during imaging studies. Pathologic evaluation by needle core biopsy remains the gold standard for diagnosis. Molecular studies have revealed that hepatic adenomas involve unique molecular pathways that are distinct from hepatocellular carcinoma. Based on these studies, a French collaborative group has recently proposed a molecular-pathologic classification for hepatic adenomas. In addition, advances in molecular studies have led to reclassification of the "telangiectatic variant of focal nodular hyperplasia" as "hepatic adenoma, inflammatory subtype."

OBJECTIVE

To review the proposed, new classification of hepatic adenoma and the changes in diagnostic workup in light of the above-mentioned developments.

DATA SOURCES

Review of published literature and illustrations from clinical case material.

CONCLUSIONS

Definitive diagnosis of liver mass lesion on needle core biopsies has a decisive role in clinical management. With the advent of the new classification of hepatic adenomas and its prognostic implications, it is vital for pathologists to be aware of the morphologic features seen in different subtypes and the available diagnostic tools, such as immunohistochemistry, to help identify the correct subtype.

International experience for laparoscopic major liver resection

Although minor laparoscopic liver resections (LLRs) appear as standardized procedures, major LLRs are still limited to few expert teams. The aim of this study was to report the combined data of 18 international centers performing major LLR. Variables evaluated were number and type of LLR, surgical indications, number of synchronous colorectal resections, details on technical points, conversion rates, operative time, blood loss and surgical margins. From 1996 to 2014, a total of 5388 LLR were carried out including 1184 major LLRs. The most frequent indication for laparoscopic right hepatectomy (LRH) was colorectal liver metastases (37.0%). Seven centers used hand assistance or hybrid approach selectively for LRH mostly at the beginning of their experience. Seven centers apply Pringle's maneuver routinely. The conversion rate for all major LLRs was 10% and mean operative time was 291 min. Mean estimated blood loss for all major LLR was 327 ml and negative surgical margin rate was 96.5%. Major LLRs still remain challenging procedures requiring important experience in both laparoscopy and liver surgery. Stimulating the younger generation to learn and accomplish these techniques is the better way to guarantee further development of this surgical field.

Benign nodular hyperplasia of the liver-pedunculated form: diagnostic contributions of ultrasonography and consideration of exophytic liver tumors

Focal nodular hyperplasia (FNH) is an asymptomatic benign liver tumor that may be detected accidentally during an abdominal ultrasound examination; it is associated with unspecific complaints, sometimes painful. Diagnosis can be precise using imaging techniques like ultrasonography. The diagnostic criteria are represented by the spatial display of the tumoral vessels and their hemodynamic characteristics. Sometimes differential diagnostic issues occur with other benign or malignant liver tumors. We present the case of a young female patient without a personal pathological history, who complained of intense, diffuse, intermittent, non-systematic abdominal pain and who underwent ultrasound examination, followed by contrast-enhanced ultrasound. With this technique, we evidenced a solid extrahepatic tumor, which was mobile at the patient's change of position and had the hemodynamic features of FNH. The article also tackles the problem of intra-abdominal pedunculated tumors.

What is changing in indications and treatment of hepatic hemangiomas. A review

Hepatic cavernous hemangioma accounts for 73% of all benign liver tumors with a frequency of 0.4-7.3% at autopsy and is the second most common tumor seen in the liver after metastases. Patients affected by hemangioma usually have their tumor diagnosed by ultrasound abdominal examination for a not well defined pain, but pain persist after treatment of the hemangioma. The causes of pain can be various gastrointestinal pathologies including cholelithiasis and peptic ulcer disease.The malignant trasformation is practically inexistent. Different imaging modalities are used to diagnosis liver hemangioma including ultrasonography, computed tomography (CT), magnetic resonance (MR) imaging, and less frequently scintigraphy, positronemission tomography combined with CT (PET/CT) and angiography. Imaging-guided biopsy of hemangioma is usually not resorted to except in extremely atypical cases. The right indications for surgery remain rupture, intratumoral bleeding, Kasabach-Merritt syndrome and organ or vessels compression (gastric outlet obstruction, Budd-Chiari syndrome, etc.) represents the valid indication for surgery and at the same time they are all complications of the tumor itself. The size of the tumor do not represent a valid indication for treatment. Liver hemangiomas, when indication exist, have to be treated firstly by surgery (hepatic resection or enucleation, open, laproscopic or robotic), but in the recent years other therapies like liver transplantation, radiofrequency ablation, radiotherapy, trans-arterial embolization, and chemotherapy have been applied.

Focal nodular hyperplasia: a review of current indications for and outcomes of hepatic resection

BACKGROUND

Focal nodular hyperplasia (FNH) is a common benign disease of the liver with no recognized potential for malignant transformation. The term describes an entity of lobular proliferation of normally differentiated hepatocytes, frequently around a central fibrous scar. Two key issues influence surgical decision making in FNH: diagnostic certainty, and symptomatic assessment.

METHODS

A systematic review of studies reporting hepatic resections of FNH was performed. Indications and outcomes in adult populations were examined with a focus on diagnostic workup, patient selection and operative mortality and morbidity.

RESULTS

Diagnostic modalities in the majority of studies involved ultrasound and computed tomography. Fewer than half employed magnetic resonance imaging (MRI). In instances in which MRI was not available, diagnostic accuracy was inferior.

CONCLUSIONS

Percutaneous biopsy should be avoided to prevent the risk for tumour seeding. Patients presenting with asymptomatic definitive FNH can be safely managed conservatively. In symptomatic patients surgical resection is a safe and effective treatment for which acceptable rates of morbidity (14%) and zero mortality are reported. However, evidence of symptom resolution is reported with conservative strategies. Diagnostic uncertainty remains the principal valid indication for FNH resection, but only in patients in whom contrast-enhanced MRI forms part of preoperative assessment.

Focal nodular hyperplasia: hepatobiliary enhancement patterns on gadoxetic-acid contrast-enhanced MRI

OBJECTIVES

To assess the range of hepatobiliary enhancement patterns of focal nodular hyperplasia (FNH) after gadoxetic-acid injection, and to correlate these patterns to specific histological features.

MATERIALS AND METHODS

FNH lesions, imaged with Gadoxetic-acid-enhanced MRI, with either typical imaging findings on T1, T2 and dynamic-enhanced sequences or histologically proven, were evaluated for hepatobiliary enhancement patterns and categorized as homogeneously hyperintense, inhomogeneously hyperintense, iso-intense, or hypo-intense-with-ring. Available histological specimens of FNHs (surgical resection or histological biopsy), were re-evaluated to correlate histological features with observed enhancement patterns.

RESULTS

26 FNHs in 20 patients were included; histology was available in six lesions (four resections, two biopsies). The following distribution of enhancement patterns was observed: 10/26 homogeneously hyperintense, 4/26 inhomogeneously hyperintense, 5/26 iso-intense, 6/26 hypointense-with-ring, and 1/26 hypointense, but without enhancing ring. The following histological features associated with gadoxetic-acid uptake were identified: number and type of bile-ducts (pre-existent bile-ducts, proliferation, and metaplasia), extent of fibrosis, the presence of inflammation and extent of vascular proliferation.

CONCLUSION

FNH lesions can be categorized into different hepatobiliary enhancement patterns on Gadoxetic-acid-enhanced MRI, which appear to be associated with histological differences in number and type of bile-ducts, and varying the presence of fibrous tissue, inflammation, and vascularization.

Liver-specific agents for contrast-enhanced MRI: role in oncological imaging

Liver-specific magnetic resonance (MR) contrast agents are increasingly used in evaluation of the liver. They are effective in detection and morphological characterization of lesions, and can be useful for evaluation of biliary tree anatomy and liver function. The typical appearances and imaging pitfalls of various tumours at MR imaging performed with these agents can be understood by the interplay of pharmacokinetics of these contrast agents and transporter expression of the tumour. This review focuses on the applications of these agents in oncological imaging.

Laparoscopic liver resection: a review

Laparoscopic liver surgery was slower to develop than other fields of laparoscopic surgery because of a steep learning curve, and fear of uncontrolled bleeding or gas embolism. However, laparoscopic liver resection (LLR) is associated with significant advantages: faster recovery, less post-operative pain, less morbidity, easier subsequent surgery and better cosmetic results. Since the inception of this technique, more than 3000 procedures have been reported. The aim of this update was to review the literature in order to define the indications (malignant tumors, benign tumors, major resections), the advantages and limits of this approach as well as the expected value of new technology, such as intra-operative guidance or robotics, in the development of this branch of surgery.

Large hepatic adenoma in a 21-year-old male

Hepatic adenoma is an uncommon benign lesion of the liver that occurs more frequently in women in their third and fourth decades. The female/male ratio is up to 11:1. Hepatic adenomas may be single or multiple occasionally reaching sizes up to 20 cm. They are non-cancerous lesions, however they can become malignant. We present a 21-year-old male patient with no medical history who presented with abdominal pain, a palpable abdominal mass, abnormal liver function tests and a 14 kg weight loss in a 2-year period. A CT scan was performed with a 17 cm tumour compressing intrahepatic bile ducts. The patient underwent a right hepatectomy with no complications. Histopathological analysis of the tumour revealed a hepatic adenoma with central necrosis. The patient is asymptomatic at 1-year follow-up.

Defining vascular signatures of benign hepatic masses: role of MDCT with 3D rendering

Multidetector CT (MDCT) provides new opportunities for hepatic tumor characterization. By coupling high-resolution isotropic datasets with advanced post-processing tools, maps of tumor vascularity can be generated to elucidate characteristic findings. This two-part review describes a range of benign and malignant liver masses, with emphasis on IV contrast-enhanced MDCT features and vascular signatures that can be identified on 3D vascular mapping.

Focal Nodular Hyperplasia and Hepatocellular Adenoma around the World Viewed through the Scope of the Immunopathological Classification

Focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) are benign hepatocellular tumors. The risk of bleeding and malignant transformation of HCA are strong arguments to differentiate HCA from FNH. Despite great progress that has been made in the differential radiological diagnosis of the 2 types of nodules, liver biopsy is sometimes necessary to separate the 2 entities. Identification of HCA subtypes using immunohistochemical techniques, namely, HNF1A-inactivated HCA (35-40%), inflammatory HCA (IHCA), and beta-catenin-mutated inflammatory HCA (b-IHCA) (50-55%), beta-catenin-activated HCA (5-10%), and unclassified HCA (10%) has greatly improved the diagnostic accuracy of benign hepatocellular nodules. If HCA malignant transformation occurs in all HCA subgroups, the risk is by far the highest in the β -catenin-mutated subgroups (b-HCA, b-IHCA). In the coming decade the management of HCA will be more dependent on the identification of HCA subtypes, particularly for smaller nodules (<5 cm) in terms of imaging, follow-up, and resection.

CT and MRI imaging at the acute phase of inaugural non-traumatic hepatic haemorrhages

PURPOSE

Although rare, non-traumatic hepatic haemorrhage is a known complication of liver tumors. In cases where the haemorrhage is the first clinical event, diagnostic work-up is critical.

MATERIAL AND METHODS

This retrospective study was conducted between July 2001 and March 2011. Acute phase CT-scan and MRI imaging in patients diagnosed with non-traumatic liver hematomas were interpreted with particular attention to the radio-semiotic characteristics of hematomas and liver lesions. Those findings were then confronted to the patients' final diagnoses.

RESULTS

Twelve patients were included (mean age of 42 years). In seven of them a suspect liver lesion was discovered in the acute CT-Scan or MRI imaging. All lesions were strongly hyper vascular.The haemorrhage revealed hepatocarcinoma in four patients, liver adenoma in two and focal nodular hyperplasia in an other.

CONCLUSION

It is important in spontaneous liver haemorrhage to consider the high probability of hepatocarcinoma or potentially malignant lesions even when the patient has no known hepatic disorders, and especially in young patients. The results of this study show that imaging is a key issue at the acute phase of inaugural non-traumatic hepatic haemorrhages and requires a simple but complete triphasic injected protocol.

[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.

Adopting Gayet's Techniques of Totally Laparoscopic Liver Surgery in the United States

Professor Brice Gayet of the Institut Mutualiste Montsouris in Paris, France, has developed totally laparoscopic techniques for all segments of the liver. As a pioneer in the field of minimally invasive hepato-pancreato-biliary surgery, he started a Minimally Invasive Hepato-Pancreato-Biliary Fellowship in 2006. A retrospective review of all hepatic cases performed by a single surgeon since completing this Fellowship was undertaken. From November 2007 to October 2012, a total of 80 liver resections were done, of which 73 were begun with the intention of completing the case laparoscopically. Of these, more than 90% were completed laparoscopically and 88% were for malignant disease. One of the foundations of Professor Gayet's techniques is the low lithotomy or 'French' position and the utilization of a small robotically controlled laparoscope holder that is sterilizeable and considerably more economic than complete surgical systems. Prototypes exist of robotically controlled hand-held laparoscopic instruments that, unlike the complete surgical system, enable surgeons to maintain a sense of touch (haptics). Proper training in minimally invasive hepato-pancreato-biliary techniques can be obtained with surgeons able to independently perform laparoscopic major hepatectomies without senior minimally invasive backup. Furthermore, miniature and more affordable robotics may enable more surgeons to enjoy the benefits of minimally invasive surgery while maintaining patient safety and minimizing the rising burden of health-care costs worldwide.

Investigation and management of hepatic incidentalomas

With the widespread use of medical imaging has come the detection of incidental liver lesions that are, by and large, asymptomatic prior to their discovery. These lesions may become a source of anxiety and often require further investigation to reassure the patient of their usually benign nature. Use of contemporary hepatobiliary imaging and simple laboratory tests often allow a definite diagnosis to be made without resorting to exhaustive investigation or inappropriate surgery. The goal of this paper is to review the clinical features and imaging characteristics of common and important liver incidentalomas, their natural course, complications, and indications for surgical or other intervention.

Co-existence of hepatocellular adenoma and focal nodular hyperplasia in a young female

Focal nodular hyperplasia (FNH) and hepatocellular adenoma (HA) are both benign hepatocellular lesions, presenting mainly in women of childbearing age in non-cirrhotic, non-fibrotic livers. Simultaneous occurrence of these two lesions is extremely rare. We herein report a case of a young female without any predisposing risk factors who presented to our emergency department complaining of acute abdominal pain. Imaging studies revealed a 6 cm lesion in the right hepatic lobe and a 2.5 cm lesion in the left hepatic lobe, respectively. In view of the patient's symptoms and lack of a confirmed diagnosis based on imaging, we performed a bisegmentectomy V-VI and a wedge resection of the lesion in segment III by laparotomy. Postoperative course was uneventful and the patient was discharged on the fourth postoperative day. The pathology report demonstrated an HA in segments V-VI and FNH in segment III, respectively. Six months later, the patient remains asymptomatic with normal liver function tests, ultrasound and magnetic resonance imaging follow-up. To our best knowledge, this is the first case to describe simultaneous occurrence of HA and FNH without the presence of any known risk factors for these entities. The uncertainty in diagnosis and acuteness of presenting symptoms were established criteria for prompt surgical intervention.

Laparoscopic liver resection: Current role and limitations

Laparoscopic liver resection (LLR) for the treatment of benign and malignant liver lesions is often performed at specialized centers. Technological advances, such as laparoscopic ultrasonography and electrosurgical tools, have afforded surgeons simultaneous improvements in surgical technique. The utilization of minimally invasive techniques for liver resection has been reported to reduce operative time, decrease blood loss, and shorten length of hospital stay with equivalent postoperative mortality and morbidity rates compared to open liver resection (OLR). Non-anatomic liver resection and left lateral sectionectomy are now routinely performed laparoscopically at many institutions. Furthermore, major hepatic resections are performed by pure laparoscopy, hand-assisted technique, and the hybrid method. In addition, robotic surgery and single port surgery are revealing early promising results. The consensus recommendation for the treatment of benign liver disease and malignant lesions remains unchanged when considering a laparoscopic approach, except when comorbidities and anatomic limitations of the liver lesion preclude this technique. Disease free and survival rates after LLR for hepatocellular carcinoma and metastatic colon cancer correspond to OLR. Patient selection is a significant factor for these favorable outcomes. The limitations include LLR of superior and posterior liver lesions; however, adjustments in technique may now consider a laparoscopic approach as a viable option. As growing data continue to reveal the feasibility and efficacy of laparoscopic liver surgery, this skill is increasingly being adopted by hepatobiliary surgeons. Although the full scope of laparoscopic liver surgery remains infrequently used by many general surgeons, this technique will become a standard in the treatment of liver diseases as studies continue to show favorable outcomes.

[Benign focal hepatic lesions]

A profound knowledge of the various benign focal hepatic lesions and selection of the most suitable radiological examination modality is essential for achieving an accurate characterization of a hepatic lesion and in turn will determine the further patient management. This will avoid unnecessary agitation to both patient and the referring clinician and limits time-consuming, costly and risky biopsies to an absolute minimum. The following article will discuss the typical and atypical appearances of the most frequent and clinically relevant benign focal hepatic lesions with ultrasound, computed tomography and magnetic resonance imaging.

Laparoscopic liver surgery: new frontiers

Laparoscopic liver resection (LHR) has shown classical advantages of minimally invasive surgery over open counterpart. In spite of introduction in early 1990's only few centres worldwide adapted LHR to routine practice. It was due to considerable technical challenges and uncertainty about oncologic outcomes. Surgical instrumentation and accumulation of surgical experience has largely enabled to solve many technical considerations. Intraoperative navigation options have also been improved. Consequently indications have been drastically expanded nearly reaching criteria equal to open liver resection in expert centres. Recent studies have verified oncologic integrity of LHR. However, mastering of LHR is still a quite demanding task limiting expansion of this patient friendly technique. This emphasizes the necessity of systematic training for laparoscopic liver surgery. This article reviews the state of the art of laparoscopic liver surgery lightening burning issues of research and clinical practice.

Molecular pathology of hepatic neoplasms: classification and clinical significance

Recent technological advances have enabled investigators to characterize the molecular genetics and genomics of hepatic neoplasia in remarkable detail. From these studies, an increasing number of molecular markers are being identified that correlate with clinically important tumor phenotypes. This paper discusses current knowledge relevant to the molecular classification of epithelial primary hepatic tumors that arise in adults, including focal nodular hyperplasia (FNH), hepatocellular adenoma (HCA), hepatocellular carcinoma (HCC), cholangiocarcinoma (CC), and combined HCC-CC. Genetic analysis has defined molecular subtypes of HCA that are clinicopathologically distinct and can be distinguished through immunohistochemistry. Gene expression studies have identified molecular signatures of progression from dysplastic nodules (DNs) to early HCC in cirrhosis. Analyses of the mutational spectra, chromosomal aberrations and instability, transcriptomics, and microRNA profiles of HCC have revealed the existence of biologically distinct subtypes of this common malignancy, with prognostic implications. Molecular characterization of biliary and hepatic progenitor cell phenotypes in liver cancer has shed new light on the histogenesis of these tumors and has focused attention on novel therapeutic targets. In coming years, the molecular classification of hepatic neoplasms will be increasingly valuable for guiding patient care, as targeted therapies for liver cancer are developed and brought into clinical practice.