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

Incidental Liver Lesions in children: A practical and evidence-based approach

Incidental liver lesions are increasingly being discovered in the context of the increased use of ultrasound studies and the majority are benign. In children, although individually rare, the differential diagnosis is broad and therefore a systematic approach is of utmost importance to reduce the radiological and disease burden in children and their families. This review article collected current evidence and provides fundamental information for the clinician regarding specific differential diagnoses and unique imaging features of benign liver lesions in children. Ultimately, we propose a practical stepwise approach mainly involving clinical and radiological workup. Laboratory tests and histopathological examination may be necessary in the presence of red flags or in indeterminate lesions.

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.

Impact of open and minimally invasive resection of symptomatic solid benign liver tumours on symptoms and quality of life: a systematic review

BACKGROUND

The value of open and minimally invasive liver resection for symptomatic solid benign liver tumours (BLT) such as hepatocellular adenoma, focal nodular hyperplasia and haemangioma is being debated. A systematic review on symptom relief, quality of life (QoL) and surgical outcome after both open and minimally invasive surgery for solid BLT is currently lacking.

METHODS

A systematic search in PubMed and EMBASE was performed according to the PRISMA guidelines (January 1985-April 2018). Articles reporting pre-and postoperative symptoms or QoL in patients undergoing open or minimally surgery for BLT were evaluated. Methodological quality was assessed using the MINORS tool.

RESULTS

Forty-two studies were included with 4061 patients undergoing surgery for BLT, 3536 (87%) open and 525 (13%) laparoscopic resections. Randomized and propensity-matched studies were lacking. Symptoms were the indication for resection in 56% of the patients. After a weighted mean of 28.5 months follow-up after surgery, symptoms were relieved in 82% of symptomatic patients. Validated QoL tools were used in eight studies, of which two found significant better QoL scores following laparoscopic compared to open surgery.

DISCUSSION

Resection of symptomatic BLT seems safe and relieves symptoms in the vast majority of selected patients. Comparative studies are needed before more firm conclusions can be drawn.

Can point shear wave elastography differentiate focal nodular hyperplasia from hepatocellular adenoma

PURPOSE

Focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) are liver tumors that require different management. We assessed the potential of point shear wave elastography (pSWE) to differentiate FNH from HCA and the interobserver and intraobserver reliability of pSWE in the examination of these lesions and of native liver tissue (NLT).

METHODS

The study included 88 patients (65 FNH, 23 HCA). pSWE was performed by two experienced liver sonographers (observers 1 [O1] and 2 [O2]) and acquired within the lesion of interest and NLT. Group differences, optimal cutoff for characterization and interobserver reliability was assessed with Mann-Whitney-U, area under the ROC curce (AUROC) and intraclass correlation coefficient (ICC). Intraobserver reliability in NLT was assessed in 20 healthy subjects using ICC.

RESULTS

Median stiffness was significantly higher in FNH than in HCA (7.01 kPa vs 4.98 kPa for O1 (P = 0.017) and 7.68 kPa vs 6.00 kPa for O2 (P = 0.031)). A cutoff point for differentiation between the two entities could not be determined with an AUROC of 0.67 (O1) and 0.69 (O2). Interobserver reliability was good for lesion- stiffness (ICC = 0.86) and poor for NLT stiffness (ICC = 0.09). In healthy subjects, intraobserver reliability for NLT-stiffness was poor for O1 (ICC = 0.23) and moderate for O2 (ICC = 0.62).

CONCLUSION

This study shows that pSWE cannot reliably differentiate FNH from HCA. Interobserver and intraobserver reliability for pSWE in NLT were insufficient. Interpretation of results gained with this method should be done with great caution.

乙型肝炎合并肝脏巨大腺瘤1例

肝细胞腺瘤(hepatocellular adenoma, HCA)是一种较为罕见的肝内良性肿瘤, 生长缓慢, 发现时体积常较大并伴出血坏死. HCA多见于年轻女性, 常与口服避孕药有关, 本文就乙型肝炎合并肝脏巨大腺瘤1例进行论述.

Benign hepatocellular nodules of healthy liver: focal nodular hyperplasia and hepatocellular adenoma

Owing to the progress of imaging techniques, benign hepatocellular nodules are increasingly discovered in the clinical practice. This group of lesions mostly arises in the context of a putatively normal healthy liver and includes either pseudotumoral and tumoral nodules. Focal nodular hyperplasia and hepatocellular adenoma are prototypical examples of these two categories of nodules. In this review we aim to report the main pathological criteria of differential diagnosis between focal nodular hyperplasia and hepatocellular adenoma, which mainly rests upon morphological and phenotypical features. We also emphasize that for a correct diagnosis the clinical context such as sex, age, assumption of oral contraceptives, associated metabolic or vascular disturbances is of paramount importance. While focal nodular hyperplasia is a single entity epidemiologically more frequent than adenoma, the latter is representative of a more heterogeneous group which has been recently and extensively characterized from a clinical, morphological, phenotypical and molecular profile. The use of the liver biopsy in addition to imaging and the clinical context are important diagnostic tools of these lesions. In this review we will survey their systematic pathobiology and propose a diagnostic algorithm helpful to increase the diagnostic accuracy of not dedicated liver pathologists. The differential diagnosis between so-called typical and atypical adenoma and well differentiated hepatocellular carcinoma will also be discussed.

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.

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.

Hepatocellular benign tumors-from molecular classification to personalized clinical care

Focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) are benign hepatocellular tumors that develop most frequently in women without cirrhosis. Genomic approaches have identified signaling pathways related to these benign hepatocyte proliferations. FNH, a polyclonal lesion, is characterized by local vascular abnormalities and heterogeneous activation of Wnt/β-catenin and transforming growth factor β signaling. Four major subgroups of HCAs have been identified based on mutations in specific oncogenes and tumor suppressor genes. Each molecular subtype of HCA has been associated with specific pathways, providing new information about benign tumorigenesis. Key features include metabolic alterations (induced by defects in HNF1A), oncogene-induced inflammation (activation of JAK-STAT signaling in inflammatory adenomas), and an association between activation of Wnt/β-catenin signaling and progression of HCAs in hepatocellular carcinomas. Benign hepatocellular tumors can be classified using immunohistochemical analyses. Studies of genotypes and phenotypes of FNH and HCAs have led to the identification of risk factors and improved invasive and noninvasive diagnostic techniques, evaluation of prognosis, and treatment. We review the molecular pathways involved in benign hepatocyte proliferation and discuss how this basic knowledge has been progressively translated into personalized clinical care.

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.

Histological and immunohistochemical revision of hepatocellular adenomas: a learning experience

Light has been shed on the genotype/phenotype correlation in hepatocellular adenoma (HCA) recognizing HNF1 α -inactivated HCA (H-HCA), inflammatory HCA (IHCA), and β -catenin-activated HCA (b-HCA). We reviewed retrospectively our surgical HCA series to learn how to recognize the different subtypes histopathologically and how to interpret adequately their immunohistochemical staining. From January 1992 to January 2012, 37 patients underwent surgical resection for HCA in our institution. Nine had H-HCA (25%) characterized by steatosis and loss of L-FABP expression; 20 had IHCA (55.5%) showing CRP and/or SAA expression, sinusoidal dilatation, and variable inflammation; and 1 patient had both H-HCA and IHCA. In 5 patients (14%), b-HCA with GS and β -catenin nuclear positivity was diagnosed, two already with hepatocellular carcinoma. Two cases (5.5%) remained unclassified. One of the b-HCA showed also the H-HCA histological and immunohistochemical characteristics suggesting a subgroup of β -catenin-activated/HNF1 α -inactivated HCA, another b-HCA exhibited the IHCA histological and immunohistochemical characteristics suggesting a subgroup of β -catenin-activated/inflammatory HCA. Interestingly, three patients had underlying vascular abnormalities. Using the recently published criteria enabled us to classify histopathologically our retrospective HCA surgical series with accurate recognition of b-HCA for which we confirm the higher risk of malignant transformation. We also underlined the association between HCA and vascular abnormalities.

Clinical features of rare benign liver tumors: A retrospective analysis of 45 cases

AIM: To analyze the clinical features of rare benign liver tumors.

METHODS: The clinical data for 45 patients with rare benign liver tumors were retrospectively analyzed. The detection rates and diagnostic accuracy of B-Ultrasound, CT and MRI were compared. The relationship between age and clinical features of patients with rare benign liver tumors was also investigated.

RESULTS: The detection rates of B-ultrasound, CT and MRI for focal liver lesions were all 100%; however, their diagnostic accuracy rates were 42.2%, 60.5% and 65.7%, respectively. Patients with liver cirrhosis were all misdiagnosed with liver cancer. The cause of symptoms in patients with rare benign liver tumors was not the rare benign tumor itself but the accompanying diseases. The incidence of rare benign liver tumors was higher in males than in females, and in patients ≥ 46 years than in those ≤ 45 years.

CONCLUSION: Lack of specific symptoms is the cause of misdiagnosis of rare benign liver tumors, and the misdiagnosis rate may be decreased by combined application of examination with B-ultrasound, CT and MRI. Further research is needed to investigate whether the incidence of rare benign liver tumors is really different between different age and gender groups.

A standard definition of major hepatectomy: resection of four or more liver segments

BACKGROUND

While commonly used to describe liver resections at risk for post-operative complications, no standard definition of 'major hepatectomy' exists. The objective of the present retrospective study is to specify the extent of hepatic resection that should describe a major hepatectomy.

METHODS

Demographics, diagnoses, surgical treatments and outcomes from patients who underwent a liver resection at two high-volume centres were reviewed.

RESULTS

From 2002 to 2009, 1670 patients underwent a hepatic resection. Post-operative mortality and severe, overall and hepatic-related morbidity occurred in 4.4%, 29.7%, 41.6% and 19.3% of all patients. Mortality (7.4% vs. 2.7% vs. 2.6%) and severe (36.7% vs. 24.7% vs. 24.1%), overall (49.3% vs. 40.6% vs. 35.9%) and hepatic-related (25.6% vs. 16.4% vs. 15.2%) morbidity were more common after resection of four or more liver segments compared with after three or after two or fewer segments (all P < 0.001). There were no significant differences in any post-operative outcome after resection of three and two or fewer segments (all P > 0.05). On multivariable analysis, resection of four or more liver segments was independently associated with post-operative mortality and severe, overall, and hepatic-related morbidity (all P < 0.01).

CONCLUSIONS

A major hepatectomy should be defined as resection of four or more liver segments.