A 13-year-old girl, melanodermic, presented with the history of sporadic abdominal pain a few years ago, worsened in the last three months, increased abdominal volume and feeling of heaviness in the abdomen. The pain was initially mild, oppressive, located mainly in the right upper quadrant of the abdomen, without reports of anorexia, nausea, vomiting, or weight loss. At the physical exam, the patient was in good general condition, stained, hydrated, and anicteric. Cardiovascular and respiratory system examination showed no alteration. Absence of adenomegaly. Abdomen bulging in epigastric and right flank regions, presence of palpable mass, hardened and painful to deep palpation, with rounded margins and firm consistency.
Admission ultrasound (US) showed liver with normal size, regular contours, homogeneous sonic echotexture, and absence of biliary tract dilatation. Presence of expansive formation, predominantly solid with cystic areas, occupying almost the entire upper abdomen, measuring about 23 cm × 16 cm. Kidneys and spleen without alterations. Laboratory tests showed mild anemia, hemoglobin of 11.8 g/dL (normal 12–17 g/dL) and hematocrit of 36.7% (normal 36–50%). Electrolytes and liver function tests were normal. Alpha-fetoprotein and human chorionic gonadotropin were also measured and were within normal limits.
Abdominal computed tomography (CT) revealed a large abdominal expansile formation, in close relation to the lateral portion of the left liver lobe (Fig. 1A). It extends to the level of L4, dislocating the stomach, transverse colon, and small bowel loops, causing a bulging of the anterior wall of the abdomen (Fig. 1B). It had well-defined limits, encapsulated, regular contours, heterogeneous content of cystic predominance, and no evidence of calcifications or fats inside. The estimated size and volume were 25 cm × 22 cm × 12.5 cm and 3595 cm3, respectively. At magnetic resonance imaging (MRI) of the abdomen, the lesion presented predominantly high signal intensity on T2-weighted sequences, with heterogeneous hypersignal content on T1-weighted sequences, with no evidence of contrast enhancement, suggesting cystic lesion with hematic content due to intracystic bleeding. Absence of dilation of the bile ducts intra and extra-hepatic and laterally displaced gallbladder.
Among the diagnostic hypotheses, the possibilities of hepatic lesion with exophytic growth (mesenchymal hamartoma, with cystic predominance) and congenital cystic lesion with heterogeneous content due to probable bleeding were considered. Although the differentiation between a hepatic cyst with a blood clot and a hepatic cystic tumor is often difficult, in this case, as MRI well reflect the morphological features of a simple hepatic cyst with intracystic bleeding, they may provide the most important information for the diagnosis. In general, simple hepatic cysts are hypointense on T1 and hyperintense on T2; however, in the presence of intracystic bleeding, they are hyperintense on both T1 and T2 [9]. In addition, disagreement between US (solid predominant lesion) and CT (cystic predominant lesion) findings is also important to establish the diagnosis of a simple hepatic cyst associated with intracystic hemorrhage, because US usually visualizes the intracystic blood clot such as papillary, nodular, or irregular septal images, and CT cannot clearly visualize the intracystic hemorrhage [10].
With the probable diagnosis of symptomatic and complicated simple hepatic cyst, surgical treatment was indicated. The patient underwent a supra and infra umbilical median laparotomy, showing a large cystic lesion, linked to segments II and III of the liver by a narrow bridge of hepatic tissue, without adherence to other organs (Fig. 2A, B). Complete excision of the lesion, which weighed 3890 g, was performed.
The postoperative period passed without complications, the patient discharged on the 5th day for follow-up in the outpatient clinic. The anatomopathological study revealed a cystic lesion covered by fibrotic wall, with entrapment of biliary ductal structures and hepatocyte parenchyma, containing macrophagic-like cells inside, a large amount of cytoplasm, hematic, and necrotic material. Immunohistochemistry confirmed cystic lesion with hemorrhagic areas covered by mucosecretory columnar epithelium simple without atypia. In the lesion wall, there was entrapment of hepatocytes and bile ducts, besides positivity for cytokeratin in the lining cells, suggesting the diagnosis of solitary biliary cyst.