Evidence of good prognosis of hepatocellular adenoma in post-menopausal women

ACG Clinical Guideline: Focal Liver Lesions

Focal liver lesions (FLLs) have become an increasingly common finding on abdominal imaging, especially asymptomatic and incidental liver lesions. Gastroenterologists and hepatologists often see these patients in consultation and make recommendations for management of multiple types of liver lesions, including hepatocellular adenoma, focal nodular hyperplasia, hemangioma, and hepatic cystic lesions including polycystic liver disease. Malignancy is important to consider in the differential diagnosis of FLLs, and healthcare providers must be familiar with the diagnosis and management of FLLs. This American College of Gastroenterology practice guideline uses the best evidence available to make diagnosis and management recommendations for the most common FLLs.

Variation in the management of benign liver tumors: A European survey and case vignette study

BACKGROUND

Management of focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA), is multidisciplinary and subject to practice variation. We aimed to evaluate variation in clinical management of FNH and HCA in Europe.

METHODS

We distributed an online survey (November 2021-March 2022) among 294 European experts. The survey included questions on local practice and included eight clinical vignettes. The clinical vignettes focused on FNH or HCA management in the setting of sex, lifestyle modification, and pregnancy.

RESULTS

The response rate was 32% and respondents included surgeons (38%), gastroenterologists/hepatologists (25%), radiologists (32%), and pathologists (1.6%) from ten European countries. We observed practice variation with regard to lifestyle modification and imaging follow-up in patients with FNH, and with regard to the management of HCA >5 cm before and during pregnancy. Finally, the management of HCA >5 cm after lifestyle modification deviated from EASL guideline recommendations.

CONCLUSION

Our survey illustrates variability in FNH and HCA management in Europe. Several areas were identified for future research and guideline recommendations, including FNH follow-up and the management of HCA >5 cm. We propose the organization of Delphi consensus meetings to prioritize areas of research and update current guidelines to optimize management for all patients with benign liver tumors.

Hepatocellular Adenomas: Molecular Basis and Multimodality Imaging Update

Hepatocellular adenomas (HCAs) are a family of liver tumors that are associated with variable prognoses. Since the initial description of these tumors, the classification of HCAs has expanded and now includes eight distinct genotypic subtypes based on molecular analysis findings. These genotypic subtypes have unique derangements in their cellular biologic makeup that determine their clinical course and may allow noninvasive identification of certain subtypes. Multiphasic MRI performed with hepatobiliary contrast agents remains the best method to noninvasively detect, characterize, and monitor HCAs. HCAs are generally hypointense during the hepatobiliary phase; the β-catenin-mutated exon 3 subtype and up to a third of inflammatory HCAs are the exception to this characterization. It is important to understand the appearances of HCAs beyond their depictions at MRI, as these tumors are typically identified with other imaging modalities first. The two most feared related complications are bleeding and malignant transformation to hepatocellular carcinoma, although the risk of these complications depends on tumor size, subtype, and clinical factors. Elective surgical resection is recommended for HCAs that are persistently larger than 5 cm, adenomas of any size in men, and all β-catenin-mutated exon 3 HCAs. Thermal ablation and transarterial embolization are potential alternatives to surgical resection. In the acute setting of a ruptured HCA, patients typically undergo transarterial embolization with or without delayed surgical resection. This update on HCAs includes a review of radiologic-pathologic correlations by subtype and imaging modality, related complications, and management recommendations. ^© RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

Development of a set of patient reported outcome measures for patients with benign liver tumours and cysts: patient focus groups and systematic review

BACKGROUND

Patient reported outcome measures (PROMs) may be useful for patients with benign liver tumours and cysts (BLTC) to evaluate the impact of treatment and/or guide shared decision making. Yet, a set of PROMs relevant to patients with BLTC is currently unavailable. In this study, we selected a PROMs set for patients with BLTC.

METHODS

Potentially relevant patient reported outcomes (PROs) were selected by psychologist-researchers based on keywords used or suggested by participants of two virtual focus groups meetings consisting of thirteen female BLTC patients with a median age of 50 years. Subsequently, patients were asked to report their most relevant PROs. PROMs identified by systematic literature review and computerized adaptive tests (CATs) in the Patient-Reported Outcomes Measurement Information System (PROMIS) were considered in selecting the final PROMs set to assess relevant outcomes.

RESULTS

The most important PROs were: insecurity/anxiety (11/12 patients), pain (9/12 patients), fatigue (8/12 patients), and limitations in daily life (5/12 patients). The literature review included 23 studies, which used various generic and disease-specific PROMs, often not measuring (all) relevant PROs. The final selected PROMs set included numerical rating scales for pain, two questions on overall health and quality of life and four PROMIS CATs.

CONCLUSIONS

A PROMs set generically and efficiently measuring outcomes relevant for patients with BLTC was developed and may be used in future research and clinical practice.

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.

Benign liver tumours: understanding molecular physiology to adapt clinical management

Improvements in understanding the pathophysiology of the different benign liver nodules have refined their nosological classification. New criteria have been identified using imaging, histology and molecular analyses for a precise diagnosis of these tumours. Improvement in the classification of liver tumours provides a more accurate prediction of disease progression and has modified patient management. Haemangioma and focal nodular hyperplasia, the most common benign liver tumours that develop in the absence of chronic liver disease, are usually easy to diagnose on imaging and do not require specific treatment. However, hepatocellular adenomas and cirrhotic macronodules can be difficult to discriminate from hepatocellular carcinoma. The molecular subtyping of hepatocellular adenomas in five major subgroups defined by HNF1A inactivation, β-catenin mutation in exon 3 or exon 7/8, and activation of inflammatory or Hedgehog pathways helps to identify the tumours at risk of malignant transformation or bleeding. New clinical, biological and molecular tools have gradually been included in diagnostic and treatment algorithms to classify benign liver tumours and improve patient management. This Review aims to explain the main pathogenic mechanisms of benign liver tumours and how this knowledge could influence clinical practice.

Hepatocellular Adenoma: What We Know, What We Do Not Know, and Why It Matters

In the last 2 decades there has been significant progress in research and diagnosis of hepatocellular adenoma (HCA), resulting in the establishment of a molecular and immunohistological HCA classification. This review aims to fine-tune the current expertise in order to enhance the histopathological diagnostic possibilities, by refining issues that are already known, addressing diagnostic difficulties and identifying still unknown aspects of HCA. We will discuss novel methods to identify HCA subtypes, in particular the sonic hedgehog HCAs and the interpretation of glutamine synthetase patterns for the recognition of beta-catenin mutated HCAs. The major complications of HCAs, bleeding and malignant transformation, will be considered, including the dilemmas of atypical and borderline lesions. Paragraphs on HCAs in different clinical and geographical settings, e.g. pregnancy, cirrhosis and non-western countries are included. The natural history of the different HCA subtypes in relation with age, sex and risk factors is a feature still insufficiently investigated. This is also true for the risks of clinical bleeding and malignant transformation in association with HCA subtypes. As HCA is a relatively rare tumor, a multicenter and multidisciplinary approach across geographical boundaries will be the appropriate method to establish prospective programs to identify, classify and manage HCAs, focusing on several aspects, e.g. etiology, underlying liver disease, complications, regression and growth. Updating what we know, identifying and addressing features that we do not know matters to warrant optimal patient management.

Scoping review of clinical practice guidelines on the management of benign liver tumours

OBJECTIVE

Benign liver tumours (BLT) are increasingly diagnosed as incidentalomas. Clinical implications and management vary across and within the different types of BLT. High-quality clinical practice guidelines are needed, because of the many nuances in tumour types, diagnostic modalities, and conservative and invasive management strategies. Yet, available observational evidence is subject to interpretation which may lead to practice variation. Therefore, we aimed to systematically search for available clinical practice guidelines on BLT, to critically appraise them, and to compare management recommendations.

DESIGN

A scoping review was performed within MEDLINE, EMBASE, and Web of Science. All BLT guidelines published in peer-reviewed, and English language journals were eligible for inclusion. Clinical practice guidelines on BLT were analysed, compared, and critically appraised using the Appraisal of Guidelines, Research and Evaluation (AGREE II) checklist regarding hepatic haemangioma, focal nodular hyperplasia (FNH), and hepatocellular adenoma (HCA). Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations (PRISMA) for scoping reviews were adhered to.

RESULTS

The literature search yielded unique 367 papers, 348 were excluded after screening of title/abstract, and 16 after full-text screening. Three guidelines were included: the American College of Gastroenterology (ACG; 2014), Brazilian Society of Hepatology (SBH; 2015), and European Association for the Study of the Liver (EASL; 2016). There was no uniformity in the assessment methods for grading and gravity of recommendations between guidelines. Among observed differences were: (1) indications for biopsy in all three tumours; (2) advices on contraceptive pills and follow-up in FNH and HCA; (3) use of an individualised approach to HCA; (4) absence of recommendations for treatment of HCA in men; and (5) approaches to HCA subtype identification on magnetic resonance imaging.

CONCLUSION

Recognising differences in recommendations can assist in harmonisation of practice standards and identify unmet needs in research. This may ultimately contribute to improved global patient care.

Ascites symptom inventory-7 is a valuable tool for evaluating the effectiveness of tolvaptan in patients with cirrhotic ascites

Patients with liver cirrhosis frequently experience non-specific symptoms and report severe reductions in their quality of life (QOL). The underlying mechanisms of the disease are multifactorial that may be specific to the disease or directly related to the liver. The major concern of liver cirrhosis with ascites, however, is the decreased QOL. Therefore, in the present study, the Ascites Symptom Inventory-7 (ASI-7) questionnaire was applied to subjectively evaluate the symptoms in patients with cirrhotic ascites following tolvaptan administration. In total, 69 patients with liver cirrhosis with ascites hospitalized to Nara Medical University were evaluated after being treated with tolvaptan (3.75-7.5 mg/day) and conventional diuretics between December 2013 and April 2018. A follow-up assessment was conducted 7 days after tolvaptan treatment, whilst ASI-7 was used on days 1 and 8 of the study. After an uneventful 7-day tolvaptan treatment regimens, 49 patients (71.0%) lost >1.5 kg of their body weight, who were referred to as responders, with the change in the ASI-7 score being found to correlate with the body weight change. By contrast, changes in urine volume did not correlate with those in the ASI-7 score. The responders experienced a greater reduction in the ASI-7 score after 7 days compared with those in the non-responders (P<0.01). ASI-7 scores were also found to correlate with body weight after tolvaptan administration. In conclusion, ASI-7 accurately reflected changes in body weight but not urine volume and results of the study highlighted the value of ASI-7 in the evaluation of ascitic volume and effectiveness of tolvaptan in cirrhotic ascites. The present clinical trial was registered onto the UMIN-Clinical Trial Registry on 1st March 2014 (registration no. UMIN000013095).

A systematic review on the complications and management of hepatic adenomas: a call for a new approach

Hepatic adenomas are benign hepatic lesions with heterogeneous characteristics. Awareness of complications, including haemorrhage and malignant transformation, has improved alongside a concurrent rise in their detection. Monitoring and management guidelines, however, remain inconsistent. This systematic review analyses the natural history of hepatic adenomas, and existing and novel risk factors associated with haemorrhage and malignant transformation. Results of this systematic review commonly identified male sex, and the beta-catenin histopathological hepatic adenoma subtype, as risk factors for malignant transformation, whilst those associated with haemorrhage included lesion size and number, exophytic nature, and recent hormone use. Overall, females demonstrated higher rates of haemorrhage, whilst males exhibited a higher risk of hepatocellular carcinoma development. This systematic review highlights that tumour size and subtype may not be as characteristically linked with complications as previously thought. We have additionally reported novel risk factors contributing to development of hepatic adenoma-related complications. We conclude by highlighting the risk of taking a conservative approach to seemingly low-risk lesions and suggest revised practice guidelines.

New insights in the management of Hepatocellular Adenoma

Hepatocellular adenoma (HCA) are benign liver tumours that may be complicated by haemorrhage or malignant transformation to hepatocellular carcinoma. Epidemiological data are fairly outdated, but it is likely to assume that the incidence has increased over the past decades as HCA are more often incidentally found due to the more widespread use of imaging techniques and the increased incidence of obesity. Various molecular subgroups have been described. Each of these molecular subgroups are defined by specific gene mutations and pathway activations. Additionally, they are all related to specific risk factors and show a various biological behaviour. These molecular subgroups may be identified using immunohistochemistry and molecular characterization. Contrast-enhanced MRI is the recommended imaging modality to analyse patients with suspected hepatocellular adenoma allowing to determine the subtype in up to 80%. Surgical resection remains to be the golden standard in treating HCA, although resection is deemed unnecessary in a large number of cases, as studies have shown that the majority of HCA will regress over time without complications such as haemorrhage or malignant transformation occurring. It is preferable to treat patients with suspected HCA in high volume centres with combined expertise of liver surgeons, hepatologists, radiologists and (molecular) pathologists.

Long-term Evolution of Hepatocellular Adenomas at MRI Follow-up

Background Hepatocellular adenomas (HCAs) are rare benign liver tumors. Guidelines recommend continued surveillance of patients diagnosed with HCAs, but these guidelines are mainly based on small studies or expert opinion. Purpose To analyze the long-term evolution of HCAs, including solitary and multiple lesions, and to identify predictive features of progression with MRI. Materials and Methods In a retrospective study, patients diagnosed with pathologically proven solitary or multiple HCAs between January 2004 and December 2015 were included; β-catenin-mutated HCAs and HCAs with foci of malignancy were considered to be at risk for progression. MRI examinations were analyzed, and tumor evolution was evaluated by using Response Evaluation Criteria in Solid Tumors, version 1.1. Student t, Mann-Whitney, χ², Fisher exact, and McNemar tests were used, as appropriate. Results In total, 118 patients (mean age, 40 years ± 10 [standard deviation]; 108 women) were evaluated, including 41 with a solitary HCA (mean age, 40 years ± 14; 36 women) and 77 with multiple HCAs (mean age, 40 years ± 10; 72 women). At a median follow-up of 5 years, 37 of 41 (90%) patients with a solitary HCA and 55 of 77 (71%) patients with multiple HCAs showed stable or regressive disease. After resection of solitary HCAs, new lesions appeared in only two of 29 (7%) patients, both of whom had HCAs at risk of progression. In patients with multiple HCAs, hepatocyte nuclear factor 1α-inactivated HCAs showed a higher rate of progression compared with inflammatory HCAs (11 of 26 [42%] vs seven of 37 [19%], P = .04) despite lower use (28 of 32 patients [88%] vs 45 of 45 patients [100%]; P = .03) and shorter duration (mean, 12.0 years ± 7.5 vs 19.2 years ± 9.2; P = .001) of oral contraceptive intake. Conclusion Long-term MRI follow-up showed that 78% of hepatocellular adenomas had long-term stability or regression. After resection of solitary hepatocellular adenomas, new lesions occurred only in hepatocellular adenomas at risk of progression. Patients with multiple hepatocellular adenomas were more likely to show progressive disease, with hepatic nuclear factor 1α-inactivated hepatocellular adenomas being the most common subtype showing progression. © RSNA, 2020 Online supplemental material is available for this article.

Development and Validation of a Model to Predict Regression of Large Size Hepatocellular Adenoma

INTRODUCTION

Surgery is advocated in hepatocellular adenomas (HCA) >5 cm that do not regress to <5 cm after 6-12 months. The aim of this study was to develop a model for these patients, estimating the probability of HCA regression to <5 cm at 1 and 2 years follow-up.

METHODS

Data were derived from a multicenter retrospective cohort of female patients diagnosed with HCA >5 cm at first follow-up. Potential predictors included age, body mass index, and HCA diameter at diagnosis (T0), HCA-subtype (hepatocyte nuclear factor 1α inactivated HCA, inflammatory-HCA, unclassified HCA) and "T0-T1 regression-over-time" (percentage of regression between T0 and first follow-up (T1) divided by weeks between T0 and T1). Cox proportional hazards regression was used to develop a multivariable model with time to regression of HCA < 5 cm as outcome. Probabilities at 1 and 2 years follow-up were calculated.

RESULTS

In total, 180 female patients were included. Median HCA diameter at T0 was 82.0 mm and at T1 65.0 mm. Eighty-one patients (45%) reached the clinical endpoint of regression to <5 cm after a median of 34 months. No complications occurred during follow-up. In multivariable analysis, the strongest predictors for regression to <5 cm were HCA diameter at T0 (logtransformed, hazard ratio (HR) 0.05), T0-T1 regression-over-time (HR 2.15) and HCA subtype inflammatory-HCA (HR 2.93) and unclassified HCA (HR 2.40), compared to hepatocyte nuclear factor 1α inactivated HCA (reference). The model yielded an internally validated c-index of 0.79.

DISCUSSION

In patients diagnosed with HCA > 5 cm that still exceed 5 cm at first follow-up, regression to <5 cm can be predicted at 1 and 2 years follow-up using this model. Although external validation in an independent population is required, this model may aid in decision-making and potentially avoid unnecessary surgery.

Repeat surgery in HNF1alpha-inactivated adenomatosis

BACKGROUND AND AIMS

Stopping oral contraceptives following nodule detection usually prevents further hepatocellular growth (HCA); rare cases of growth have been reported after surgery. The aim of the study was to review our resected HCA cases and their outcomes and more specifically, growth.

METHODS

We retrieved all HCA cases that required a second intervention and HCA growth cases of none resected HCA after resection of one or several HCAs.

RESULTS

Out of the 210 resected classified HCA cases, a second resection was performed in 5 cases, 4 of which were in women with HNF1alpha-inactivated adenomatosis (H-adenomatosis) and had a favorable outcome. The fifth case was the occurrence of an inflammatory HCA, 3 years after resection of a previous one. Of the 65 resected HNF1-inactivated HCAs (H-HCAs), the nodules that remained continued to increase very slowly in 3 adenomatosis cases. After surgery, the liver became dysmorphic years later in one case, and the nodules grew but not significantly in another case. After the diagnosis of adenomatosis, progressive growth leads to surgery 12 years later in the last case.

CONCLUSION

These results confirm that, in rare H-adenomatosis, size of nodules may increase very slowly, probably in part through coalescence of micro H-HCAs and leading occasionally to a second resection.

The effect of oral contraceptive pill cessation on hepatocellular adenoma diameter: A retrospective cohort study

BACKGROUND & AIMS

Hepatocellular adenomas (HCA) are rare, hormone-driven, benign liver tumours. HCA >50 mm are associated with haemorrhage and malignant transformation. Guidelines recommend cessation of oral contraceptive pills (OCP) for size reduction; however, it is currently unknown how HCA respond to cessation of OCP. We sought to investigate the effect of OCP cessation on HCA size.

METHODS

A retrospective cohort study was performed including HCA patients who stopped OCP intake within 6 months of imaging between 2005 and 2018. Biometrics and hormonal medication use were evaluated with self-designed questionnaires. Response of the largest HCA was evaluated according to Response Evaluation Criteria in Solid Tumours (RECISTv1.1). Cox regression was performed for analysis of factors influencing HCA regression.

RESULTS

Seventy-eight HCA patients were included, diagnosed at a median (interquartile range) age of 32 (26-41) years. Follow-up was 1.6 (0.4-2.9) years. HCA size at diagnosis ranged 10-167 mm. After a median time of 1.3 (0.6-2.6) years after OCP cessation, 37.2% of HCA showed ≥30% regression, 5.1% complete regression, 56.4% stability and 1.3% progression. No HCA-induced complications were observed during follow-up. Cox regression analysis demonstrated a significant association of HCA size with rate of regression; 50 ≤ HCA < 100 mm (HR 2.4, 95% CI 1.1-5.3; P < 0.05), HCA ≥ 100 mm (HR 8.3, 95% CI 3.3-21.6; P < 0.001).

CONCLUSIONS

Ninety-eight per cent of HCA remained stable or regressed after OCP cessation. A longer wait-and-see period was associated with a larger proportion of regressing HCA, without HCA-related complications during follow-up.

Uncommon evolutions and complications of common benign liver lesions

Frequently encountered on abdominal imaging studies, the majority of common benign liver lesions are asymptomatic, confidently diagnosed by imaging, and do not require further workup, follow-up, or treatment. The increasing use of multimodality liver imaging, has allowed the recognition of uncommon evolutions of common benign liver lesions such as size changes, fibrotic regression, and content and vascularization changes, and their complications such as rupture, hemorrhage, thrombosis, extrinsic compression, and malignancy. The purpose of this pictorial review is to describe and illustrate the incidence and diagnostic features of these uncommon evolutions and complications on cross-sectional imaging, mainly on computed tomography and magnetic resonance imaging, with emphasis on those imaging clues which are helpful in the differential diagnosis or indicate the need for treatment.

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.

Unexpected discovery of small HNF1α-inactivated hepatocellular adenoma in pathological specimens from patients resected for liver tumours

BACKGROUND AND AIMS

It is rare but not uncommon to discover micro/small HNF1α-inactivated hepatocellular adenoma (H-HCA) outside the context of resected H-HCA. We aimed to review our cases of micro/small H-HCA discovered by chance on different kinds of liver resected specimens.

METHODS

We retrieved cases of micro/small H-HCA discovered by chance on resected specimens outside the context of H-HCA. All these nodules were liver fatty acid binding protein (LFABP)-negative contrasting with normal positivity in the surrounding non-tumoural liver, ruling out the possibility of focal steatosis or other subtypes of micro-HCAs.

RESULTS

We identified 19 micro/small H-HCA cases. In 16 cases they were discovered in patients who underwent surgery for benign nodules including one haemangioma, six focal nodular hyperplasia, seven inflammatory HCA (including one with b-catenin activation), one HCA, whose subtype could not be identified because of massive necrosis/hemorrhage, and one hepatocellular carcinoma. In two additional cases, patients followed up for a melanoma underwent liver surgery to remove micro nodules possibly related to a metastatic process. Finally in one case a micro nodule was seen and resected during a cholecystectomy.

CONCLUSION

Taken together, H-HCAs are more frequent than we initially supposed as micro and small HCAs cannot all be detected by routine ultrasound. Despite no information on the potential growth of these micro/small H-HCAs, there is no argument to stop oral contraceptives or to ask for a specific regular surveillance. The association of different subtypes of HCAs with focal nodular hyperplasia suggests they share or have common etiological factors.

Retrospective study on timing of resection of hepatocellular adenoma

Background

Hepatocellular adenoma (HCA) is a benign liver tumour that may be complicated by bleeding or malignant transformation. Present guidelines advise cessation of oral contraceptives and surgical resection if the lesion is still larger than 5 cm at 6 months after diagnosis. The aim of this study was to evaluate whether this 6-month interval is sufficient to expect regression of a large HCA to 5 cm or smaller.

Methods

This retrospective cohort study included all patients with an HCA larger than 5 cm diagnosed between 1999 and 2015 with follow-up of at least 6 months. Medical records were reviewed for patient characteristics, clinical presentation, lesion characteristics, management and complications. Differences in characteristics were assessed between patients kept under surveillance and those who underwent treatment for an HCA larger than 5 cm.

Results

Some 194 patients were included, of whom 192 were women. Eighty-six patients were kept under surveillance and 108 underwent HCA treatment. Patients in the surveillance group had a significantly higher BMI (P = 0·029), smaller baseline HCA diameter (P &lt; 0·001), more centrally located lesions (P &lt; 0·001) and were more likely to have multiple lesions (P = 0·001) than those in the treatment group. There were no significant differences in sex, age at diagnosis, symptoms, complication rates and HCA subtype distribution. Time-to-event analysis in patients managed conservatively and those still undergoing treatment more than 6 months after diagnosis showed that 69 of 118 HCAs (58·5 per cent) regressed to 5 cm or smaller after a median of 104 (95 per cent c.i. 80–128) weeks. Larger HCAs took longer to regress (P &lt; 0·001). No complications were documented during follow-up.

Conclusion

This study suggests that a 6-month cut-off point for assessment of regression of HCA larger than 5 cm to no more than 5 cm is too early. As no complications were documented during follow-up, the cut-off point in women with typical, non-β-catenin-activated HCA could be prolonged to 12 months, irrespective of baseline diameter.