Unique genetic alterations and clinicopathological features of hepatocellular adenoma in Chinese population

Hepatic adenoma: evolution of a more individualized treatment approach

BACKGROUND

Hepatic adenomas (HAs) are benign, solid liver lesions, which carry a risk of hemorrhage and malignant transformation. This review article highlights the advances in the diagnosis and management of HAs.

METHODS

A comprehensive review was performed using MEDLINE/PubMed and Web of Science databases with a search period ending on September 30, 2023. Using PubMed, the terms "hepatocellular," "hepatic," and "adenoma" were searched.

RESULTS

HA has been classified into at least 8 subtypes based on molecular pathology, each exhibiting unique histopathologic features, clinical considerations, and risk of malignant transformation. The most common subtype is inflammatory HA, followed by hepatocyte nuclear factor 1α-inactivated HA, β-catenin exon 3-mutated HA (βex3-HA), β-catenin exon 7- or 8-mutated HA, sonic hedgehog HA, and unclassified HA. Magnetic resonance imaging is the best imaging method for diagnosis and can distinguish among HA subtypes based on fat and telangiectasia pathologic characteristics. The risk of malignant transformation varies among molecular subtypes, ranging from <1% to approximately 50%. Up to 42% of HAs present with spontaneous intratumoral hemorrhage and peritoneal hemorrhage. In general, only 15% to 20% of patients require surgery. HA larger than 5 cm are more likely to be complicated by bleeding and malignant transformation, regardless of subtype, and should generally be resected. In particular, βex3-HA carries a high risk of malignant transformation and can be considered a true precancerous lesion.

CONCLUSION

The management of HAs is based on a multidisciplinary approach. Clinical decision-making should integrate information on gender, tumor size, and HA subtyping. In the future, patients with HA will benefit from novel medical therapies tailored to the individual molecular subtypes.

Hepatic adenoma in a 7-year-old girl: a case report and literature review

BACKGROUND

Hepatocellular adenomas (HCAs) are rare benign tumors of the liver that occur predominantly in women taking oral contraceptives. In children, HCAs comprise < 5% of hepatic tumors. We report a case of HCAs in a 7-year-old girl with estrogen and glucose imbalance.

CASE PRESENTATION

A 7-year-old girl was presented to our hospital with bilateral breast enlargement for 2 months, polydipsia, polyuria, polyphagia, hyperglycemia, and significant weight gain. Computed tomography (CT) showed a 7.2 cm×6.9 cm×5.3 cm round-shaped mass in the left inner lobe of the liver, ovarian ultrasound showed multiple follicles in the ovaries bilaterally, and cranial magnetic resonance imaging (MRI) showed an enlarged superior pituitary. Hematological and biochemical results were as follows: fasting glucose was 19.7 mmol/L, estradiol was 122.9 pmol/L, follicle-stimulating hormone 10.81 IU/L, luteinizing hormone 10.99 IU/L, insulin-like growth factor 1,513 ng/mL, glutamine aminotransferase 86 U/L, and alkaline phosphatase 362 U/L. Thyroid functions, methemoglobin, fetal protein, carcinoembryonic antigen, and chorionic gonadotropin were normal. The patient had a complete surgical resection of the liver tumor, and the postoperative histopathological diagnosis was HCAs. After the surgery, insulin was injected and the glucose levels were stable. During the 36-month follow-up period, neither tumor recurrence nor significant abnormalities were detected using color Doppler ultrasound of the liver. The child's precocious puberty is currently under control.

CONCLUSIONS

HCAs are particularly rare in children with liver tumors, and risk factors for the development of HCAs in children include sex hormone imbalance, obesity, Fanconi anemia (FA), glycogen storage diseases (GSDs) type I, III, and IV, galactosemia, immunodeficiency, congenital portosystemic shunts (CPSS), cardiac hepatopathy status-post Fontan procedure, Hurler syndrome, familial adenomatous polyposis, germline HNF1A mutations, and maturity-onset diabetes of the young type 3. Most HCAs are detected during a physical examination without clinical symptoms, and some patients may present with symptoms such as abdominal pain, abdominal distension, and abdominal masse. Serum liver function tests can show increased alkaline phosphatase (ALP) and γ- glutamyl transferase (GT), whereas α-Fetoprofein (AFP) levels are normal. The definitive diagnosis relies mainly on histopathological examination. Because HCAs can rupture and bleed and become malignant. Early surgical treatment is recommended after detection.

Hepatocellular adenoma initially diagnosed as hepatocellular carcinoma with resistance to proton beam radiotherapy - A case report

Introduction and importance

Hepatocellular adenoma (HCA) is a rare liver tumor. We report a case of a radio-resistant liver tumor that was removed surgically and found to be HCA.

Case presentation

A 37-year-old Japanese man was incidentally diagnosed with a liver tumor. He had no history of viral hepatitis nor metabolic disorders. MRI revealed a tumor enhancing in arterial phase, followed by washout in late phase, and hypointensity in hepatobiliary phase. A diagnosis of hepatocellular carcinoma (HCC) was made and surgery was advised. However, the patient chose proton beam radiotherapy. Although the tumor initially shrunk, it increased in size thereafter. Therefore, anterior sectionectomy was performed. Histology revealed proliferation of hepatocytes without cytologic atypia. On immunohistochemistry, CRP, SAA, GS, L-FABP, and nuclear expression of β-catenin were positive. A final diagnosis of mixed inflammatory and β-catenin activated HCA was made.

Clinical discussion

HCA is associated with obesity. The present case was a slightly obese man without history of viral hepatitis. In such cases, HCA should be considered. In the present case, proton beam radiotherapy was performed for a diagnosis of HCC. However, the tumor was radio-resistant.

Conclusion

HCA shows an almost equal male to female ratio in the Asian population. Molecular classification is vital in the management of HCA. HCC and HCA are often difficult to differentiate; tumor biopsy is necessary for patients with atypical imaging findings and in younger patients without underlying liver disease. Since the effectiveness of radiation therapy on HCA has not been reported, surgery should be preferred.

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HCA is more prevalent in women in the western countries, while equal gender distribution in Asian countries

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Subgroups show different imaging findings. I-HCA, atoll sign; b-HCA, iso-hyperintensity in the hepatobiliary phase

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In the present case, the tumor showed resistance to radiation

Hepatocellular adenomas: recent updates

Hepatocellular adenoma (HCA) is a heterogeneous entity, from both the histomorphological and molecular aspects, and the resultant subclassification has brought a strong translational impact for both pathologists and clinicians. In this review, we provide an overview of the recent updates on HCA from the pathologists’ perspective and discuss several practical issues and pitfalls that may be useful for diagnostic practice.

Hepatocellular adenoma in Taiwan: Distinct ensemble of male predominance, overweight/obesity, and inflammatory subtype

BACKGROUND AND AIM

The clinicopathologic features of hepatocellular adenoma in Asian populations have been poorly defined. The study aimed to characterize this rare entity in a single institution in Taiwan.

METHODS

In total, 45 hepatocellular adenomas from 1995 to 2018 were included and sent for pathologic review and molecular subtyping.

RESULTS

The numbers of patients with hepatocellular adenoma has doubled in the recent decade. Surprisingly, men outnumbered women in our cohort (n = 26, 58% vs N = 19, 42%). A collection of clinical information revealed that overweight/obesity accounts for most of the associated conditions of hepatocellular adenoma. Only three women took oral contraceptives. There were 34 inflammatory (75%), three LFABP-negative (7%), four β-catenin activated (9%), and four unclassified (9%) hepatocellular adenomas. Ten inflammatory hepatocellular adenomas demonstrated strong and homogeneous glutamine synthetase staining and were thus also β-catenin activated. Notably, overweight and obesity were significantly associated with inflammatory hepatocellular adenoma than other subtypes (P = .029 and .056, respectively) and were strongly correlated with steatosis in background liver (P = .028 and.007, respectively). Malignant transformation (four borderline tumors and two hepatocellular carcinomas) was identified in six adenomas (two women and four men). All six hepatocellular adenomas with malignancy were β-catenin activated; β-catenin activation could serve as a biomarker for malignant progression.

CONCLUSIONS

The clinicopathologic features of hepatocellular adenoma in Taiwan are distinct from those reported in Western countries. Rare oral contraceptive usage and an emerging epidemic of overweight/obesity in Taiwan provides new insights into the pathogenesis of hepatocellular adenoma.

MR imaging of hepatocellular adenomas on genotype-phenotype classification: A report from China

PURPOSE

To investigate and compare the MR features between hepatocellular adenoma (HCA) subtypes in China, including preliminary observations on diffusion-weighted imaging (DWI).

METHODS

Thirty-six patients with 39 pathologically proven HCAs underwent gadopentetate dimeglumine enhanced MRI. The morphological and imaging features on T1, T2-weighted, dynamic-enhanced imaging and DWI were retrospectively evaluated and compared between four HCA subtypes, using Kruskal-Wallis test, Fisher's exact test and Dunn-Bonferroni post hoc test.

RESULTS

HCA frequently occurred in male (n = 19, 52.8%), lacked an association with oral contraceptives (n = 0), and had a relatively high incidence of coexistent Hepatitis B infection (n = 6, 16.7%). Signals on T1 and T2-weighted imaging, enhancement pattern and intensity, lesion heterogeneity, as well as accompanying findings including lesion steatosis, necrosis or cystic component, central scar, and pseudocapsule were different between HCA subtypes (P < .0001 to P = .019). Apparent diffusion coefficient (ADC) values among HCA subtypes were different as a whole (P = .029), within which β-catenin-mutated HCA had the lowest ADCs; but post hoc comparisons demonstrated no significant differences between groups (P = .066-1.000).

CONCLUSION

Both clinical and MR imaging presentation of HCA in China had some specific characteristics, and a good relationship existed between MR data and genotype-phenotype classification. Furthermore, ADC value may provide a potential indicator of malignant transformation.