Benign Hepatic Tumors and Liver Transplantation: A Literature Review

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.

Surgical indications for solid hepatic benign tumors: An updated literature review

Hepatic hemangioma, focal nodular hyperplasia, and hepatic adenoma are the most common benign solid liver tumors. However, their surgical indications have been the subject of debate. Minimally invasive liver resection reduces the cost of surgery and may lead to overtreatment of benign liver tumors. Recently, there has been a growing understanding of the etiology, pathogenesis, and natural history of these tumors. Great progress has also been made in imaging. The use of MRI and contrast agents has improved the accuracy of non-invasive diagnosis of these tumors, and especially in the identification of specific molecular subtypes of liver adenoma. These factors have resulted in alterations of surgical indications for these tumors. This article examines recent literature and it discusses the surgical indications for hepatic hemangioma, focal nodular hyperplasia, and hepatic adenoma while summarizing modifications in clinical management.

The surgical outcomes and risk factors of giant hepatic haemangiomas: a single centre experience

Objective

To evaluate the safety of performing surgery on cavernous haemangiomas in the liver larger than 10 cm and establish preoperative predictors of intraoperative blood transfusion and morbidity.

Methods

A total of 373 patients with haemangiomas larger than 10 cm who underwent surgery in our hospital were retrospectively analysed. According to tumour diameter, the patients were divided into a giant haemangioma (GH) group (241 cases) (10 cm ≤ diameter < 15 cm) and an enormous haemangioma (EH) group (132 cases) (diameter ≥ 15 cm). Clinical parameters were then compared between the two groups.

Results

Compared with the GH group, the EH group had higher rates of leukopenia (10.6% vs. 4.5%), anaemia (26.5% vs. 15.7%), and thrombocytopenia (13.6% vs. 6.2%). The occlusion time in the EH group was longer than that in the GH group (26.33 ± 14.10 min vs. 31.85 ± 20.09 min, P < 0.01). The blood loss and blood transfusion in the EH group were greater than those in the GH group (P < 0.05). Moreover, the morbidity in the EH group was higher than that in the GH group (17.4% vs. 9.13%, P < 0.05). According to the results of the multivariable analysis, the operation time and size of the haemangioma may be independent risk factors for blood transfusion (P < 0.05). Additionally, the size of the haemangioma may be an independent risk factor associated with complications (P < 0.05).

Conclusion

Enormous haemangioma is more likely to cause haematologic abnormalities than giant hepatic haemangioma. The risks of the operation and postoperative complications of enormous haemangioma are higher than those of giant hepatic haemangioma.

Updated information regarding management of hepatic epithelioid hemangioendothelioma

Hepatic epithelioid hemangioendothelioma (HEHE) is a rare hepatic vascular tumor with a borderline biological behavior between hemangioma and hemangiosarcoma. It tends to be multiple or diffuse subcapsular lesions across the liver but has no characteristic clinical manifestations or imaging findings. On computed tomography and magnetic resonance imaging, these lesions usually have a hypodense appearance with heterogeneous enhancement and a "halo sign" or "lollipop sign" may be evident in some cases. HEHE is diagnosed mainly based on a pathological examination along with differential immunohistochemical markers such as CAMTA1, CD31, CD34, CD10, vimentin, and factor VIII antigen. Currently, there are no standardized treatment guidelines for HEHE, and surgery (curative resection and liver transplantation) remains the mainstay of treatment. Studies have indicated that extra-hepatic metastasis might not be a contraindication for resection or transplantation. Systemic chemotherapeutic agents including doxorubicin, vincristine, interferon-a, 5-fluorouracil, and thalidomide, as well as VEGF-related agents are being investigated, but no agents have been approved for the treatment of HEHE.