Focal nodular hyperplasia: what are the indications for resection?

Benign liver lesions 2022: Guideline for clinical practice of Associazione Italiana Studio del Fegato (AISF), Società Italiana di Radiologia Medica e Interventistica (SIRM), Società Italiana di Chirurgia (SIC), Società Italiana di Ultrasonologia in Medicina e Biologia (SIUMB), Associazione Italiana di Chirurgia Epatobilio-Pancreatica (AICEP), Società Italiana Trapianti d'Organo (SITO), Società Italiana di Anatomia Patologica e Citologia Diagnostica (SIAPEC-IAP) - Part II - Solid lesions

Benign liver lesions are increasingly diagnosed in daily clinical practice due to the growing use of imaging techniques for the study of the abdomen in patients who have non-specific symptoms and do not have an increased risk of hepatic malignancy. They include simple or parasitic hepatic cysts and solid benign tumors which differ widely in terms of prevalence, clinical relevance, symptoms and natural history and often lead to significant clinical problems relating to diagnosis and clinical management. Following the need to have updated guidelines on the management of benign focal liver lesions, the Scientific Societies mainly involved in their management have promoted the drafting of a new dedicated document. This document was drawn up according to the present Italian rules and methodologies necessary to produce clinical, diagnostic, and therapeutic guidelines based on evidence. Here we present the second part of the guideline, concerning the diagnosis and clinical management of hemangioma, focal nodular hyperplasia, and hepatocellular adenoma.

Case Report: Rare Acute Abdomen: Focal Nodular Hyperplasia With Spontaneous Rupture

Focal nodular hyperplasia (FNH) of the liver is a benign lesion characterized by hypertrophic nodules with central star-shaped fibrous scars. The etiology and pathogenesis of FNH are not completely understood. A 43-year-old man was hospitalized because of acute abdominal pain. Emergency computed tomography(CT) showed hepatic tumor rupture and bleeding. The patient’s condition improved following arteriographic embolization to stop bleeding. Laparotomy confirmed spontaneous rupture and hemorrhage of focal hyperplasia and the patient remains asymptomatic after an uneventful recovery. FNH with spontaneous rupture and bleeding is extremely rare. Currently, there is no unified management standard for FNH and most previous studies recommend observation and follow-up. We recommend consideration of surgical treatment of cases with spontaneous rupture and bleeding.

Liver: glucose metabolism and 18F-fluorodeoxyglucose PET findings in normal parenchyma and diseases

Liver has a complex and unique energy metabolism and plays a major role in glucose homeostasis. Liver is the main control center for glycogenesis, glycogenolysis, glycolysis and gluconeogenesis which are essential to provide energy for other tissues. Liver meets its own energy need from various sources which is mainly glucose in the fed state and fatty acids in the fasting state. In this review article, we will mainly describe the glucose metabolism of the liver, effect of various factors on 18F-fluorodeoxyglucose (FDG) activity/uptake in the normal liver and 18F- FDG positron emission tomography (PET) uptake patterns in various malignant and benign liver pathologies. Brief information on metabolomics profiling analyses in liver disorders will also be provided.

RESSECÇÃO LAPAROSCÓPICA DE TUMORES BENIGNOS DO FÍGADO: POSIÇÃO ATUAL

The main indications of the use of laparoscopic liver surgery (LLS), in the early days, were benign liver lesions. As LLS became more popular, indications for malignant diseases outnumbered those for benign ones. This study aims to rule out the indications and results of LLS for the treatment of benign liver tumors.

Trauma laparotomy for the usual reasons, but for unusual causes

The impact of synchronous diseases or conditions on operative management of Trauma patients is not well established. In trauma patients, secondary diagnoses may complicate the treatment strategy and lead to changes in management and potentially outcomes. We present 5 unusual trauma cases and we discuss the difficulties and the outcomes we experienced in managing these patients.

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.

Early- and intermediate-term outcome of transarterial embolization for symptomatic hepatic focal nodular hyperplasia

Purpose: To evaluate the early- and intermediate-term outcome in patients with symptomatic hepatic focal nodular hyperplasia (FNH) treated with transarterial embolization using bleomycin-iodinated oil and polyvinyl alcohol (PVA) particles. Materials and methods: In this two-center retrospective study between January 2005 and December 2013, 27 consecutive patients with symptomatic hepatic FNH underwent superselective catheterization by microcatheter techniques and embolization using bleomycin-iodinated oil combined with PVA. Early-term (3-41 months) follow-up of TAE was performed in terms of symptom control, changes in lesion size, and complications. Intermediate-term (45-112 months) follow-up was carried out to assess symptom control and reinterventions for recurrence. Results: Embolization was performed in 27 patients with 31 lesions. Technical success was achieved in all cases. The follow-up period ranged from three to 112 months. At early-term follow-up, mean lesion diameters were decreased significantly from 6.4±2.7 cm pre-intervention to 3.6±1.8 cm at 3-9 months after embolization (P<0.001). A total of 7 lesions had complete resolution during the whole follow-up period. At intermediate-term follow-up, local recurrence was found in 1 treated lesion at 54-months. Contrast-enhanced scans showed complete lack of residual arterial blood supply in the majority of lesions during the follow-up period. There was no major complication associated with the procedure. Conclusion: Transarterial embolization using bleomycin-iodinated oil and PVA is a feasible, safe and effective alternative in both early- and intermediate-terms for the treatment of symptomatic hepatic FNH.

Hepatic Lesions Associated With McCune Albright Syndrome

McCune-Albright syndrome (MAS) results from a GNAS gene mutation. It is associated with café au lait macules, fibrous dysplasia, and several endocrinopathies to include gonadotropin-independent precocious puberty, growth hormone excess, Cushing syndrome, thyroid disease, and renal phosphate wasting. It is recognized to be a rare cause of neonatal cholestasis. We describe the hepatic outcome of 3 children with MAS referred to a single national liver unit. All presented with high gamma-glutamyl transpeptidase cholestasis and hepatitis. Cholestasis resolved by 1 year; but hepatic inflammation persisted, and 2 children developed progressive atypical focal nodular hyperplasia and 1 developed hepatoblastoma. This the first reported malignant hepatic lesion associated with MAS. MAS should be considered part of the differential diagnosis of neonatal cholestasis and affected children should be closely monitored for the development of hepatic lesions with regular liver ultrasound and alpha fetoprotein level.

Growth of Focal Nodular Hyperplasia is Not a Reason for Surgical Intervention, but Patients Should be Referred to a Tertiary Referral Centre

Background

When a liver lesion diagnosed as focal nodular hyperplasia (FNH) increases in size, it may cause doubt about the initial diagnosis. In many cases, additional investigations will follow to exclude hepatocellular adenoma or malignancy. This retrospective cohort study addresses the implications of growth of FNH for clinical management.

Methods

We included patients diagnosed with FNH based on ≥2 imaging modalities between 2002 and 2015. Characteristics of patients with growing FNH with sequential imaging in a 6-month interval were compared to non-growing FNH.

Results

Growth was reported in 19/162 (12%) patients, ranging from 21 to 200%. Resection was performed in 4/19 growing FNHs; histological examination confirmed FNH in all patients. In all 15 conservatively treated patients, additional imaging confirmed FNH diagnosis. No adverse outcomes were reported. No differences were found in characteristics and presentation of patients with growing or non-growing FNH.

Conclusion

This study confirms that FNH may grow significantly without causing symptoms. A significant increase in size should not have any implications on clinical management if confident diagnosis by imaging has been established by a tertiary benign liver multidisciplinary team. Liver biopsy is only indicated in case of doubt after state-of-the-art imaging. Resection is deemed unnecessary if the diagnosis is confirmed by multiple imaging modalities in a tertiary referral centre.

Indications for liver surgery in benign tumours

Background

Management of benign liver tumours (BLT) is still object of discussion. Uncertainty still exists about patient selection, details of management, indications for surgical intervention and potential surgery-related complications. The up-to-date strategies for management of the most common benign solid tumours are recapitulated in this article. In addition, recommendations concerning practical issues are presented.

Methods

Available data from peer-reviewed publications associated with the major controversies concerning treatment strategies of solid BLT were selected through a PubMed literature search.

Results

Non-randomized controlled trials, retrospective series and case reports dominate the literature. Conservative management in BLT is associated with low overall morbidity and mortality when applied in an appropriate patient population. Surgical intervention is indicated solely in the presence of progressive symptoms and suspicion of a malignant change. Linking abdominal symptoms to BLT should be interpreted with caution. No evidence is recorded for malignant transformation in haemangiomas and focal nodular hyperplasia (FNH), while a subgroup of hepatocellular adenoma (HCA) is associated with malignancy. Follow-up controls of BLT at 3 and 6 months should be sufficient to prove the stability of the lesion and its benign nature, after which no long-term follow-up is required routinely. However, many questions regarding this topic remain without definitive answers in the literature.

Conclusion

Conservative management of solid BLT is a worldwide trend, but the available literature does not provide high-grade evidence for this strategy. Consequently, further prospective investigations on the unclear aspects are required. Hence, this article summarises practical highlights of therapeutic strategies.

What is Changing in Indications and Treatment of Focal Nodular Hyperplasia of the Liver. Is There Any Place for Surgery?

Focal nodular hyperplasia (FNH) is a common benign liver tumor, which occurs in the vast majority of the cases in young women. FNH represents a polyclonal lesion characterized by local vascular abnormalities and is a truly benign lesion without any potential for malignant transformation. A retrospective single institution analysis of 227 FNH patients, treated from 1990 to 2016 and a review of studies reporting surgical therapy of overall 293 patients with FNH was performed. Indications for resection with a focus on diagnostic workup, patient selection, surgical mode and operative mortality and morbidity have been analysed. Ninety three patients underwent elective hepatectomy and 134 patients observation alone, where median follow-up was 107 months. Postoperative complications were recorded in 14 patients, 92% of patients reported an improvement with respect to their symptoms. Overall among 293 patients underwent surgery in the series, included to this review, there was a morbidity of 13%, where median follow-up was 53 months. Systematic follow-up remains the gold standard in asymptomatic patients with FNH. However elective surgery should be considered in symptomatic patients, in those with marked enlargement and in case of uncertainty of diagnosis. Surgery for FNH is a safe procedure with low morbidity and very good long term results as far as quality of life after surgery is concerned and surely an integral part of the modern management of FNH.

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.

Combined dynamic contrast-enhanced liver MRI and MRA using interleaved variable density sampling

PURPOSE

To develop and evaluate a method for volumetric contrast-enhanced MRI of the liver, with high spatial and temporal resolutions, for combined dynamic imaging and MR angiography (MRA) using a single injection of contrast agent.

METHODS

An interleaved variable density (IVD) undersampling pattern was implemented in combination with a real-time-triggered, time-resolved, dual-echo 3D spoiled gradient echo sequence. Parallel imaging autocalibration lines were acquired only once during the first time frame. Imaging was performed in 10 subjects with focal nodular hyperplasia (FNH) and compared with their clinical MRI. The angiographic phase of the proposed method was compared with a dedicated MR angiogram acquired during a second injection of contrast.

RESULTS

A total of 21 FNH, three cavernous hemangiomas, and 109 arterial segments were visualized in 10 subjects. The temporally resolved images depicted the characteristic arterial enhancement pattern of the lesions with a 4-s update rate. Images were graded as having significantly higher quality compared with the clinical MRI. Angiograms produced from the IVD method provided noninferior diagnostic assessment compared with the dedicated MR angiogram.

CONCLUSION

Using an undersampled IVD imaging method, we have demonstrated the feasibility of obtaining high spatial and temporal resolution dynamic contrast-enhanced imaging and simultaneous MRA of the liver.

Hepatocellular carcinoma and other liver lesions

Patients with cirrhosis are at greatest risk for development of hepatocellular carcinoma (HCC) and should undergo semiannual surveillance using ultrasound, with or without alpha fetoprotein. Patients with positive surveillance testing should undergo contrast-enhanced MRI or 4-phase CT for diagnostic evaluation. There are therapeutic options for most patients with any tumor stage; however, treatment decisions must be individualized after accounting for degree of liver dysfunction and patient performance status. A multidisciplinary approach to care is recommended for optimal communication and treatment delivery. The aim of this review is to provide an up-to-date summary of the diagnosis and management of HCC.

Focal Nodular Hyperplasia

Focal nodular hyperplasia (FNH) is the second most common benign hepatic mass. The primary purpose of this article is to provide a relevant case study and offer a review of the recent literature related to FNH with a discussion of both the clinical and imaging findings of this classically benign hepatic lesion. Although magnetic resonance imaging is considered the gold standard of FNH imaging, the sonographic and computed tomography appearance also is offered in this article. Furthermore, contrast-enhanced ultrasound, which boasts a 96% success rate at differentiating FNH from other hepatic tumors, is analyzed. The historical treatment options, including medical and possible surgical intervention, are provided as well. Last, this article offers an analysis of the prognosis for the patient diagnosed with FNH.

Management of the focal nodular hyperplasia of the liver: evaluation of the surgical treatment comparing with observation only

BACKGROUND

Long-term results of both surgery and observation for patients with focal nodular hyperplasia (FNH) in a large single-center experience do not exist. Accordingly, the aim of this study was to compare long-term outcomes in patients with FNH who underwent either elective hepatectomy or observation alone.

METHODS

A retrospective single-institution analysis of 185 patients with FNH, treated from 1990 to 2009, was performed.

RESULTS

Seventy-eight patients underwent elective hepatectomy and 107 patients observation alone, with a median follow-up period of 113 months. There was no perioperative mortality. Postoperative complications were recorded in 12 patients, and 92% of patients reported symptomatic reductions. Among observation patients, 9 (13%) developed additional symptoms; tumor enlargement was seen in 3 patients (4%).

CONCLUSIONS

Elective liver resection for FNH is a safe procedure at high-volume centers. This single-center experience showed that 13% of observed patients had protracted symptoms. This justifies the therapeutic algorithm that elective surgery should be considered in symptomatic patients or in those with marked enlargement.

Focal nodular hyperplasia--a review of myths and truths

BACKGROUND

Focal nodular hyperplasia (FNH) is a benign hyperplastic lesion of the liver with no known malignant potential. It has generated much interest due to the frequency with which it presents with atypical features on radiological imaging. Often resulting in misdiagnosis. Moreover, the understanding of particular subtypes of this lesion at a molecular level has changed in recent years. This may have implications on how certain subtypes should be managed.

PURPOSE

This review aims to analyse current literature pertaining to FNH and to provide clinically relevant advice regarding diagnosis and management.

Solid hypervascular liver lesions: accurate identification of true benign lesions on enhanced dynamic and hepatobiliary phase magnetic resonance imaging after gadobenate dimeglumine administration

PURPOSE

To evaluate hepatobiliary phase magnetic resonance imaging with gadobenate dimeglumine for differentiation of benign hypervascular liver lesions from malignant or high-risk lesions.

METHODS AND MATERIALS

Retrospective assessment was performed of 550 patients with 910 hypervascular lesions (302 focal nodular hyperplasia [FNH], 82 nodular regenerative hyperplasia [NRH], 59 hepatic adenoma or liver adenomatosis [HA/LA], 329 hepatocellular carcinomas [HCC], 12 fibrolamellar-HCC [FL-HCC], 21 peripheral cholangiocarcinomas [PCC], 105 metastases). Imaging was performed before and during the arterial, portal-venous, equilibrium, and hepatobiliary phases after gadobenate dimeglumine administration (0.05 mmol/kg). Histologic confirmation was available for ≥1 lesion per patient, except for patients with suspected FNH (diagnosis based on characteristic enhancement/follow-up). Lesion differentiation (benign/malignant) on the basis of contrast washout and lesion enhancement (hypo-/iso-/hyperintensity) was assessed (sensitivity, specificity, accuracy, PPV, and NPV) relative to histology or final diagnosis.

RESULTS

On portal-venous or equilibrium phase images, washout was not seen for 208 of 526 (39.5%) malignant (HCC, FL-HCC, PCC, metastases) and high-risk (HA/LA) lesions. Conversely, only 5 of 384 (1.3%) true benign lesions (FNH/NRH) showed washout. Taking washout as indicating malignancy, the sensitivity, specificity, and accuracy for malignant lesion identification during these phases was 61.8%, 98.7%, and 77.4%. On hepatobiliary phase images, 289 of 302 FNH, 82 of 82 NRH, 1 of 59 HA or LA, 62 of 341 HCC or FL-HCC, and 2 of 105 metastases were hyperintense or isointense. Taking iso- or hyperintensity as an indication for lesion benignity, the sensitivity, specificity, accuracy, PPV, and NPV for benign lesion identification was 96.6%, 87.6%, 91.4%, 85.1%, and 97.3%, respectively.

CONCLUSIONS

Hepatobiliary phase imaging with gadobenate dimeglumine is accurate for distinguishing benign lesions from malignant or high-risk lesions. Biopsy should be considered for hypointense lesions on hepatobiliary phase images after gadobenate dimeglumine.

An update on indications for treatment of solid hepatic neoplasms in noncirrhotic liver

During recent years, we have experienced an increased detection of previously unsuspected liver masses in otherwise asymptomatic patients owing to the widespread application of imaging techniques. Regardless of the malignant or cystic tissues, a remarkable percentage of these masses are represented by benign solid neoplasms. Treatment of benign liver tumors still represents a major concern in the hepatic surgery field. Indications for surgery have remained unchanged for many years, but the laparoscopic approach could determine in some cases a broadening of indications, which may result in overtreatment. In this article, the main surgical indication for hepatic hemangioma, focal nodular hyperplasia and hepatocellular adenoma are discussed with regard to the most recent advancements in literature. In addition, a separate section deals with the role of laparoscopy in the treatment of benign liver neoplasms.

MR imaging of hypervascular liver masses: a review of current techniques

Major technologic advances in magnetic resonance (MR) imaging, including the advent of novel pulse sequences (eg, diffusion-weighted and steady-state free precession sequences) and the use of hepatocyte-specific contrast agents, have led to better image quality and shorter acquisition times, resulting in dramatic improvements in the noninvasive detection and characterization of hepatic lesions, particularly hypervascular neoplasms. However, as the role of MR imaging in clinical evaluation of the liver continues to evolve, keeping abreast of new developments can be daunting as well as confusing. A systematic approach that makes use of a simple decision algorithm can help differentiate hypervascular hepatic lesions on the basis of their distinguishing MR imaging characteristics and related clinical information.

Focal nodular hyperplasia of the liver and elevated alpha fetoprotein level in an infant with isolated hemihyperplasia

A case of focal nodular hyperplasia of the liver in a 43-day-old baby girl with isolated hemihyperplasia and elevated serum alpha-fetoprotein is presented. The child referred to our hospital with bilateral renal masses detected by prenatal and postnatal ultrasonography. A mass lesion was detected in segment 6 of liver and was diagnosed as focal nodular hyperplasia. We present this case to emphasize the presence of focal nodular hyperplasia in a patient with isolated hemihypertrophy and elevated serum alpha-fetoprotein level.