Mesothelial cyst of the round ligament of the liver

A colic mesothelial cyst, mimicking an appendicular mucocoele in an elderly patient: A case report and a literature review

ABSTRACT

Benign cystic mesothelioma is a very rare and uncommon lesion, first reported by Plaut in 1928. It affects young women of reproductive age. It is usually asymptomatic or has non-specific symptoms. Diagnosis remains difficult despite the evolution of imaging, and the histopathological study is the key examination to make the diagnosis. Surgery remains the only curative treatment, regardless of significant rate of recurrence, and until today, no consensus on the therapeutic strategy is established.

Hepatic Benign Cystic Mesothelioma in Adults: A Case Report of a Rare Hepatic Cyst

Benign cystic mesothelioma (BCM), also known as peritoneal inclusion cyst, is a benign mesothelial lined cystic lesion, nearly always described in the pelvis of adult females. The hepatic location of BCM is rarely reported in the literature. We report a case of hepatic benign cysts in a 65-year-old woman that was incidentally discovered by imaging studies 12 years ago as a small cyst. Recently, the patient started having abdominal discomfort, distension, and anxiety. A CT scan revealed two low-density fluid-filled cystic lesions, the largest in the caudate lobe measuring up to 10.7 cm and causing a mass effect on hepatic veins and inferior vena cava. Laparoscopic marsupialization of the large liver cyst was done without complications. On gross examination, the collapsed cyst wall was a thin partly translucent pale tan to pink membranous structure with fine vascularity. No discrete nodularity or solid lesion was identified. Microscopic examination showed a thin fibro-connective wall lined by a single layer of flat cuboidal cells with no cellular atypia. The cyst lining showed characteristic calretinin-positive immunohistochemical reactivity for mesothelium, supporting the diagnosis of BCM. Hepatic BCM is among a broad differential spectrum of cystic liver lesions ranging from developmental, reactive, inflammatory, and infectious lesions, benign to premalignant or frankly malignant neoplasms with different treatment strategies. Although BCM is the rarest among the long list of differential diagnoses of hepatic cysts, its identification in this rarely reported location is essential to avoid aggressive surgical treatment.

Approach to Cystic Lesions in the Abdomen and Pelvis, with Radiologic-Pathologic Correlation

Cystic lesions found in and around the peritoneal cavity can often be challenging to diagnose owing to significant overlap in imaging appearance between the different entities. When the cystic lesion can be recognized to arise from one of the solid abdominal organs, the differential considerations can be more straightforward; however, many cystic lesions, particularly when large, cannot be clearly associated with one of the solid organs. Cystic lesions arising from the mesentery and peritoneum are less commonly encountered and can be caused by relatively rare entities or by a variant appearance of less-rare entities. The authors provide an overview of the classification of cystic and cystic-appearing lesions and the basic imaging principles in evaluating them, followed by a summary of the clinical, radiologic, and pathologic features of various cystic and cystic-appearing lesions found in and around the peritoneal cavity, organized by site of origin. Emphasis is given to lesions arising from the mesentery, peritoneum, or gastrointestinal tract. Cystic lesions arising from the liver, spleen, gallbladder, pancreas, urachus, adnexa, or soft tissue are briefly discussed and illustrated with cases to demonstrate the overlap in imaging appearance with mesenteric and peritoneal cystic lesions. When approaching a cystic lesion, the key imaging features to assess include cyst content, locularity, wall thickness, and presence of internal septa, solid components, calcifications, or any associated enhancement. While definitive diagnosis is not always possible with imaging, careful assessment of the imaging appearance, location, and relationship to adjacent structures can help narrow the differential diagnosis. Online supplemental material is available for this article. ^©RSNA, 2021.

Mesothelial cyst of the spleen mimicking a metastasis: a case report

Mesothelial cyst of the spleen is a developmental disorder. Previous reports have elaborated on the radiological features of splenic mesothelial cysts as being unilocular with a smooth and well-defined margin. However, due to its rarity, it is unclear whether these characteristics are representative and specific for the diagnosis of mesothelial cysts. Herein, this case report presents an atypical case of splenic mesothelial cyst mimicking a malignant tumour, especially splenic metastasis in a 66-year-old woman with ascending colon cancer. Due to an overlapping imaging finding of hypodense splenic lesions, and considering the clinical history, a mesothelial cyst that developed as a multilocular hypodense mass from an ill-defined small nodule was inevitably misdiagnosed as metastasis. Although rare, it is important to consider the possibility of mesothelial cyst in a patient with multilocular hypodense lesions of the spleen.

Pancreatic mesothelial cyst

A 60-year-old woman was investigated for abdominal pain and increasing asthenia. Abdominal CT revealed a 25 mm hypodense cystic lesion in the tail of the pancreas. MRI showed a multiloculated cystic lesion, T1-hypointense and T2-hyperintense lesion, without wall enhancement. Endoscopic ultrasound detected a 25 mm multi-loculated cystic lesion, with regular margin and without pancreatic duct communication. Diagnosis of pancreatic mucinous cystadenoma was discussed and the patient was referred to surgery. She underwent distal pancreatectomy with spleen preservation. Pathological examination revealed the diagnosis of pancreatic mesothelial cyst. Histologically, the cyst was multiloculated, lined by cuboidal epithelium, ovoid nuclei and amphophilic cytoplasm, without mucin deposition or cytological atypia. Immunohistochemistry examination revealed positive staining for cytokeratin 5/6, vimentin and calretinin. At 1-year follow-up, she is in her usual health, without any symptoms.

Large falciform ligament cyst in a child: A rare entity of peritoneal cysts and review of the literature

Peritoneal cysts are not uncommon in children - mesenteric/omental cysts being the commoner entity. Peritoneal cysts in the falciform ligament are a very rare entity reported in the literature. We present a 5-year-old boy who presented with pain upper central abdomen and few episodes of non-bilious vomiting for 1 year. He was stable on examination, with abdominal examination revealing the fullness of the abdomen with palpable generalised cystic mass which was mobile transversely. Ultrasound and contrast-enhanced computed tomography of the abdomen revealed intra-peritoneal cystic lesion measuring 13 cm × 11.5 cm × 9 cm with septations seen in the abdominal cavity from the epigastric region to the infraumbilical region (D11-L5 level). Laparoscopy showed a large cyst of the abdomen arising from the anterior abdominal wall, along the falciform ligament. The dark yellow fluid was aspirated and the cyst was excised leaving a part which was adherent to the anterior wall. Histopathology revealed cuboidal epithelium lined by the fibrous wall. The patient is doing well at 6 months follow-up. Falciform ligament cysts are very rare and laparoscopy can confirm the diagnosis as well as help in excision of the cyst with good results.

Mesothelial cyst in the liver round ligament: A case report and review of the literature

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Liver round ligament’s cysts are rare entities.

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Due to the low incidence of this pathology the true etiology is unclear.

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A correct diagnosis is difficult to achieve preoperatively and it is often obtained only after surgical excision.

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Today, laparoscopy should be regarded as the treatment of choice for mesenteric cysts.

Introduction

Cysts of the liver round ligament are rare and they are benign in the majority of cases. Current literature has been reviewed on this subject.

Presentation of case

A 22-year-old woman with a history of epigastric pain was admitted at our institution. Computed tomography (CT) of the abdomen showed a 14-mm cystic lesion in the epigastrium. A large cyst of the liver round ligament was successfully removed during exploratory laparoscopy and histopathology revealed a benign mesothelial cyst.

Discussion

Mesothelial cysts of the liver round ligament are rare entities and we found a total of 5 cases from the literature. Diameter varies from 5 to 14 cm. Most patients were asymptomatic or may complain abdominal pain in the upper quadrants. Ultrasonography and CT scan are the most useful diagnostic tools, however differential diagnosis between various abdominal cystic lesions can be difficult. Treatment is usually surgical excision.

Conclusion

Mesothelial cysts of the liver round ligament are extremely rare but should be taken in consideration in the differential diagnosis of intra-abdominal cystic lesions. We stress the importance of exploratory laparoscopy that can allow both diagnosis and radical surgical excision.

Laparoscopically Resected Solitary Metastasis of Hepatocellular Carcinoma to the Round Ligament

Hepatocellular carcinoma (HCC) is known to metastasize to the lung, lymph node, and musculoskeletal regions; however, to our knowledge, metastasis to the round ligament of the liver has never been reported. In addition, because the conventional approach for surgical resection of intra-abdominal metastasis is open surgery, the laparoscopic approach has been rarely performed. This report presents the case of a 72-year-old Asian man who developed a tumor in the round ligament, a rare site for distant metastases, 2 years after complete resection of an HCC. As the tumor was solitary and noninvasive, laparoscopic resection was planned and safely performed. He has now been free of recurrence for more than 3 years. Good perioperative outcomes and a long-term disease-free survival were thus achieved with minimally invasive surgery. In addition to being the first report of this rare recurrence site, this is also the first reported case of resection of an extrahepatic metastasis by laparoscopic surgery alone. This report may encourage surgeons to select a laparoscopic approach when managing intra-abdominal metastases from an HCC.