Undifferentiated (embryonal) sarcoma of the liver (USL): MRI findings including dynamic gadolinium enhancement

Undifferentiated embryonal sarcoma of liver with macroaneurysms and arteriovenous shunt

Undifferentiated embryonal sarcoma (UES) is an uncommon primary hepatic tumour of childhood. The mass usually shows paradoxical features of being cystic on CT and solid on ultrasound. These lesions are usually hypovascular. Very rarely they may present as hypervascular liver masses with macroaneurysms and arteriovenous (AV) shunt, with only less than six cases reported in literature. We report a case of an 11-year-old child who presented with progressive abdominal distention, and CT revealed a large exophytic hypervascular mass of liver with multiple macroaneurysms, pooling of contrast and a high-flow AV shunt. Histopathology, along with immunohistochemistry, revealed the mass to be UES. The child underwent neoadjuvant chemotherapy followed by successful surgery. The prognosis of this tumour depends on prompt diagnosis and early intervention. We present this case to highlight the atypical presentation of UES, which will encourage radiologists to keep this differential in relevant clinical settings.

Non-cirrhotic hepatocellular carcinoma in chronic viral hepatitis: Current insights and advancements

Primary liver cancers carry significant morbidity and mortality. Hepatocellular carcinoma (HCC) develops within the hepatic parenchyma and is the most common malignancy originating from the liver. Although 80% of HCCs develop within background cirrhosis, 20% may arise in a non-cirrhotic milieu and are referred to non-cirrhotic-HCC (NCHCC). NCHCC is often diagnosed late due to lack of surveillance. In addition, the rising prevalence of non-alcoholic fatty liver disease and diabetes mellitus have increased the risk of developing HCC on non-cirrhotic patients. Viral infections such as chronic Hepatitis B and less often chronic hepatitis C with advance fibrosis are associated with NCHCC. NCHCC individuals may have Hepatitis B core antibodies and occult HBV infection, signifying the role of Hepatitis B infection in NCHCC. Given the effectiveness of current antiviral therapies, surgical techniques and locoregional treatment options, nowadays such patients have more options and potential for cure. However, these lesions need early identification with diagnostic models and multiple surveillance strategies to improve overall outcomes. Better understanding of the NCHCC risk factors, tumorigenesis, diagnostic tools and treatment options are critical to improving prognosis and overall outcomes on these patients. In this review, we aim to discuss NCHCC epidemiology, risk factors, and pathogenesis, and elaborate on NCHCC diagnosis and treatment strategies.

Clinical and imaging characteristics of primary hepatic sarcomatoid carcinoma and sarcoma: a comparative study

Background

Primary hepatic sarcomatous carcinoma (PHSC) and primary hepatic sarcoma (PHS) are rare malignancies with frequent overlap in both the clinic and radiology. No comparative study of these tumors for the restricted cases has previously been undertaken. The purpose of our study was to analyze the clinical and imaging features of PHSCs and PHSs, with an emphasis on particularities and similarities through a comparison of the two tumors.

Methods

We retrospectively analyzed the clinical and imaging features of 39 patients with pathologically proven PHSCs (n = 23) and PHSs (n = 16) from four university centers over a 9-year period from 2010 to 2019. Univariate analyses were performed to determine the consistent and distinctive features.

Results

The background of chronic hepatitis or cirrhosis was observed with a high frequency in both of PHSCs (73.7%) and PHSs (62.5%). Tumors with a diameter greater than 10 cm were significantly more common in PHSs than PHSCs (p = 0.043) and cystic masses were more detected in PHSs (P = 0.041). Both PHSCs and PHSs mainly presented hypovascularity (78.3% vs 81.3%). The ring hyper enhancement on the arterial phase (AP) and wash out were more frequently seen in PHSCs and the iso-hypo enhancement on the AP followed persistent or progressive enhancement was more commonly detected in PHSs (all, p < 0.05).

Conclusion

PHSC and PHS generally present as mass lesions with hypovascularity. The ring hyper enhancement on the AP and wash out favor the diagnosis of PHSC. The large size greater than 10 cm, cystic lesion, iso-hypo persistent or progressive enhancement pattern might suggest the possibility of PHSs.

Primary malignant tumours in the non-cirrhotic liver

Intrahepatic chlangiocarcinomas (CCs), the second most common primary malignant liver tumours, usually occur in non-cirrhotic liver, and can be classified into three types based on gross morphology: mass-forming; periductal infiltrating; and intraductal growing. Among them, mass-forming intrahepatic CCs are the most common type and characterized by homogeneous mass with an irregular but well-defined margin with peripheral enhancement on late arterial phase and delayed enhancement in central portion of tumours corresponding to the fibrous stroma. Several imaging features such as enhancement pattern and degree of diffusion restriction have been suggested as prognostic markers for mass-forming CCs. Hepatocellular carcinomas (HCCs) are the most common primary malignant liver tumors, and usually arise from the cirrhotic liver. However, approximately 20% of HCCs involve the non-cirrhotic liver (hereafter, non-cirrhotic HCC), and non-cirrhotic HCCs are often detected at an advanced stage due to the lack of surveillance for patients with non-cirrhotic liver. Other primary malignant liver tumours other than CCs and HCCs including angiosarcoma, undifferentiated embryonal sarcoma are quite rare, and imaging diagnosis is often difficult. This review offers a brief overview of epidemiology, risk factors and imaging features of primary malignant tumours in non-cirrhotic liver. Understanding of radiologic appearance and predisposing clinical features as well as differentials of primary malignant tumour in non-cirrhotic liver can be helpful for radiologists to adequately assess these tumours, and subsequently to make optimal management plan.

A rare large symptomatic simple hepatic cyst

A fit and well 4-year-old girl presented with a 1-year history of abdominal distension, pain and vomiting with signs of non-shifting dullness on the right side of the abdomen. An abdominal CT revealed a 19 cm epigastric cyst that did not appear to connect to any solid organ and was therefore thought to represent a mesenteric cyst. However, laparotomy revealed that the cyst was arising from the liver. The cyst was resected and subsequent histology revealed a simple hepatic cyst. The patient has been well post-operation. The case represents the largest described simple hepatic cyst in the 0-16 years paediatric age group in Europe to date. We outline the epidemiology, embryology, key investigations and management options for these lesions.

Paradoxical hepatic tumor: Undifferentiated embryonal sarcoma of the liver

Undifferentiated embryonal sarcoma (UES) is a rare primary malignant tumor of the liver that typically presents in late childhood. We report a case of primary UES, which had a typical paradoxical appearance on different imaging modalities.

Embryonal sarcoma of the liver in an adult mimicking complicated hepatic cyst: MRI findings

Radiologically, embryonal sarcoma reveals a characteristic spectrum of both solid and cystic features. However, MRI is sometimes unable to reveal the solid components. Here, we describe a case in which intracystic hemorrhage revealed a solid mural nodule obscured with the cystic lesion. Knowledge of this feature is helpful when making a prospective diagnosis of this important, albeit rare, hepatic malignancy.

A case of embryonal sarcoma of the liver mimicking a hydatid cyst in an adult

An undifferentiated (embryonal) liver sarcoma (ULS) originates from a primitive mesenchymal cell, with a predilection for childhood and very rare occurrence in adults. We report a case of a ULS that was incidentally found in a 53-year-old female. Our case was initially interpreted as a large hydatid cyst, which was later suspected to be a neoplastic lesion because its size was increasing and a solid portion was newly detected after shrinkage of the cyst following drainage. The patient underwent successful right hepatic lobectomy with complete resection, and is currently disease-free without adjuvant therapy. Although it is difficult to diagnose a hepatic cyst as a ULS due to its rare occurrence in adulthood and lack of specific findings, its possibility should be considered, especially when its size is increasing, because early diagnosis and curative resection are necessary for a favorable outcome.

Undifferentiated embryonal sarcoma of liver in an old female: Case report and review of the literature

The clinical characteristics of undifferentiated (embryonal) sarcoma of the liver (UESL) were investigated and the best treatment modalities were recommended. Both histology and immuno-histochemistry demonstrated the cellular features of this peculiar tumor. The tumor size was 12 cm × 9 cm × 8 cm in the right liver lobe. The patient underwent surgical resection of the tumor. The postoperative recovery was uneventful and she died eight months after diagnosis. The tumor showed mixed spindle and polygonal cells within the myxoid matrix. Some tumor cells contained eosinophilic hyaline globules that were positive for resistant diastase. Immunohistochemistry showed positive vimentin. Stellate and spindle cells were positively stained with alpha-1-antichymotrypsin (AACT) and CD68. This case indicates that UESL is not obviously differentiated in old-aged adults.

Pediatric liver: focal masses

Imaging is a standard part of the evaluation of pediatric liver disease. Advances in MR imaging have improved detection, characterization, and staging of hepatic lesions. This article addresses the MR imaging appearances of various focal hepatic lesions that can present in children. Techniques for performing hepatic MR imaging also are reviewed.

Primary hepatic sarcomas: CT findings

Primary hepatic sarcomas are rare tumors that are difficult to diagnose clinically. Different primary hepatic sarcomas may have different clinical, morphologic, and radiological features. In this pictorial review, we summarized computed tomography (CT) findings of some relatively common types of hepatic sarcomas, including angiosarcoma, epithelioid hemangioendothelioma (EHE), liposarcoma, undifferentiated embryonal sarcoma (UES), leiomyosarcoma, malignant fibrous histiocytoma (MFH), and carcinosarcoma (including cystadenocarcinosarcoma). To our knowledge, hepatic cystadenocarcinosarcoma has not been described in the English literature. The CT findings in our case are similar to that of cystadenocarcinoma, a huge, multilocular cystic mass with a large mural nodule and solid portion. The advent of CT has allowed earlier detection of primary hepatic sarcomas as well as more accurate diagnosis and characterization. In addition, we briefly discuss the MRI findings and diagnostic value of primary hepatic sarcomas.