Inferior vena cava (IVC) leiomyosarcomas are rare smooth muscle neoplasms that account for 0.5% of adult soft tissue sarcomas. They present with nonspecific symptoms and have poor prognosis. We present a case of leiomyosarcoma arising from the retrohepatic IVC that was difficult to diagnose on imaging, showing similar characteristics to intrahepatic cholangiocarcinoma including heterogenous arterial phase enhancement and delayed enhancement on contrast-enhanced magnetic resonance imaging. Important differentiating features of IVC leiomyosarcomas on imaging include dilated IVC, imperceptible IVC lumen, and development of prominent venous collaterals. Despite this, imaging features may be similar to other retrohepatic mass etiologies so IVC leiomyosarcoma should be included in the differential diagnosis of any retrohepatic mass and biopsy should be pursued.

Combined hepatocellular cholangiocarcinoma (cHCC-CC) is a rare and poorly understood primary liver cancer. First identified over a century ago, it has been referred to by various names and reclassified multiple times since the initial description. Diagnosis is extremely challenging as the tumor can mimic hepatocellular carcinoma (HCC) or intrahepatic cholangiocarcinoma (ICC) on imaging or show overlapping features of both. The tumor may also be incorrectly diagnosed with biopsy due to inadequate tissue sampling. As such, many tumors are only correctly diagnosed histologically following surgical resection or transplantation for presumptive HCC. A variety of treatment options are available, although no national or international consensus exists regarding the optimal treatment strategy. Treatment outcomes vary with cHCC-CC showing an intermediate prognosis between HCC and ICC. In this updated review, we provide a conceptual overview of this intriguing neoplasm, including its classification and origins, epidemiology, clinical characteristics, and diagnostic and treatment options. Finally, we discuss the use of radiomics artificial intelligence (AI) to address challenges in lesion differentiation from HCC and ICC, and in predicting post-treatment survival and recurrence.

History An asymptomatic 45-year-old man with sickle cell disease and coinherited α-thalassemia was referred to the hepatology department for workup of an indeterminate hepatic mass discovered incidentally at screening cardiac MRI. The patient was diagnosed with sickle cell disease in childhood and required several hospitalizations with blood transfusions. During adulthood, disease management was suboptimal, with infrequent transfusion therapy and undertreated chronic hemolytic anemia. There was no history of malignancy, hepatitis B or C infection, alcohol consumption, metabolic syndrome, diabetes, or fatty liver disease. There was no evidence of tuberous sclerosis, glycogen storage disease, or anabolic steroid use. Laboratory investigations demonstrated chronic hemolytic anemia, with a hemoglobin level of 98–109 g/L (reference range, 135–175 g/L) and markedly elevated reticulocyte count (207.9 × 10 ⁹ /L to 247.8 × 10 ⁹ /L; reference range, 25 × 10 ⁹ /L to 75 × 10 ⁹ /L). Peripheral blood smear showed sickle cells, target cells, and Howell-Jolly bodies. Liver enzymes, synthetic liver function, and tumor markers (α-fetoprotein, carbohydrate antigen 19-9, and carcinoembryonic antigen) were within normal limits. There was no evidence of systemic iron overload. Abdominal US ( Fig 1 ), abdominal MRI ( Figs 2 , 3 ), and chest CT ( Fig 4 ) were performed.

Primary hepatic angiosarcoma (PHA) is a rare hepatic mesenchymal tumor that accounts for 2% of all primary malignant liver tumors. It typically presents with nonspecific symptoms, is highly aggressive, and there are limited treatment options. Imaging characteristics of PHA overlap with that of hepatic hemangioma, a common benign hepatic lesion, creating a potential diagnostic pitfall. We present a case of PHA that mimicked hepatic hemangioma on imaging. We review the differentiating characteristics between these two hepatic tumors. PHAs demonstrate irregular/infiltrating margins, higher lesion multiplicity, higher risk of tumor rupture, and rapid growth, which are not typically seen with hepatic hemangiomas.