*6.1.1 Ultrasound*

*Liver Disease and Surgery*

mutated subtype.

patients with HAs.

**6. Diagnosis and differential diagnosis**

**5. Signs and symptoms**

The conditions that predispose to adenomatosis and evolution of the disease are poorly understood, since the medical literature reports only information in regard to individual cases or small case series, but some similarities with the HA are evident: the tendency toward hemorrhage (especially in adenomas larger than 4 cm) and the risk of malignant transformation. Adenomas in hepatic adenomatosis may be of inflammatory, hepatocyte nuclear factor 1 alpha mutated, or beta-catenin

Most commonly, HA goes unnoticed due to its lack of signs and symptoms, but when it does become symptomatic, it is either due to its increase in volume, tumor necrosis, or complications such as life-threatening intra-abdominal bleeding due to spontaneous rupture of the highly vascularized tumor. Sudden, severe pain with hypotension in a patient with HA indicates rupture into the peritoneum, an event associated with a mortality of up to 20 percent if not identified and/or treated accordingly [9, 31, 32]. The risk of bleeding is difficult to estimate overall, but it is quite high in patients with symptomatic HAs (25–64%). Tumor size that exceeds 35 mm has been associated with an increased risk of bleeding [33]. The risk of bleeding depends on the localization of the tumor. Exophytic lesions (protruding from liver) had the highest risk of bleeding (67%), followed by subcapsular ones (19%) and at last intrahepatic HA (11%). Lesions in segments II and III had more bleeds than those in the right liver (34% versus 19%). The visualization on imaging of peripheral or central arteries represents a risk of bleeding comparative with no visible vascularization in the lesion [33]. Also a long history of contraceptive use and recent hormonal use are risk factors for bleeding from HA. Young age seems to be associated with an increased incidence of HA rupture, independent of hormonal treatment duration, suggesting a need for careful surveillance or prophylactic treatment in this population [34]. Bleeding is graded as intratumoral (grade I), intrahepatic (grade II), or extrahepatic (grade III) and represents a potentially life-threatening complication in

Hepatic adenomas are diagnosed when they cause epigastric or upper quadrant pain or during an imaging study done for unrelated ailments, and less commonly when an abdominal mass is palpated on clinical examination. When HA is sufficiently large and compresses bile ducts, jaundice may become another sign.

There are no specific serologic markers or laboratory findings for HA, but certain findings can lead the diagnosis away from an adenoma and toward a liver cell carcinoma in case of an increased serum alpha-fetoprotein, or toward a metastasis in the case of increased serum tumor markers for digestive tract tumors [35].

The definite diagnosis in this pathology is naturally a histological one; however, obtaining it preoperatively means making a biopsy from a fragile and highly vascular tissue, with significant risk of bleeding. Having to deal with a benign lesion, and given the fact that the amount of tissue obtained is rarely enough or suitable for a diagnosis, this risk is not justified. Thus, the diagnosis of this tumor is based on analyzing a combination of epidemiologic and clinical data and imaging studies, but often the confirmation of the diagnosis is done by the pathologist, after the

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hepatic resection.

The most accessible, cost-friendly, and probably responsible for most discoveries of asymptomatic HA is the ultrasound, even though it cannot distinguish it from other liver tumors. On gray scale ultrasound, HA is seen as a well-defined solid, echogenic mass, but sometimes as complex hyper/hypoechoic, heterogeneous mass with anechoic areas due to fat, hemorrhage, necrosis, and calcifications; a capsule may also be seen [36]. Color Doppler US can aid in the distinction from FNH in the absence of a central arterial signal, FNH having characteristic intratumoral and peritumoral vessels [37, 38]. Contrast-enhanced ultrasound with sulfur hexafluoride microbubbles (SonoVue or Lumason) greatly improves diagnosis as compared to US without contrast.
