Single-center Experience in the Diagnosis and Treatment of Hepatic Perivascular Epithelioid Cell Neoplasm

Abstract

Background and Aims: Perivascular epithelioid cell neoplasms (PEComas) are a rare type of mesenchymal neoplasm and their preoperative diagnosis is challenging. In this study, we summarized the experience from a single medical center to study the examinations, clinical presentations, and pathological and histological characteristics of PEComas in the liver in order to optimize overall understanding of the diagnosis and treatment of these neoplasms. Methods: We conducted a retrospective analysis to investigate the clinical and pathological characteristics as well as imaging presentations of 75 patients diagnosed with hepatic PEComa in The First Affiliated Hospital of Zhejiang University between April 2010 and April 2020. Results: Among the 75 patients, 52 were women, and the median age was 48 years. Most patients had no specific symptoms, and two were admitted to the hospital for a second time owing to relapse. All patients underwent surgical resection. Histologically, 38 patients had classical angiomyolipoma (AML) and 37 had epithelioid AML. The PEComas were accompanied by positive immunohistochemical expression of HMB45, Melan-A, and smooth muscle actin. Follow-up data were obtained from 47 of the total 75 patients, through October 2020. Two patients had metastasis after surgery. Conclusions: AML is the most common type of hepatic PEComa. There are no specific symptoms of hepatic PEComa, and serological examinations and imaging modalities for accurate preoperative diagnosis are lacking. Epithelioid AML should be considered a tumor of uncertain malignant potential; however, the prognosis of PEComa after resection is promising.

Case report: Liver PEComa after kidney transplantation in recipient with tuberous sclerosis complex

“…Unrecommended terminology is still in use. eAML is often included in the analysis with cAML which is confusing ( 15 , 16 ) and makes it impossible to distinguish between the characteristics of both groups. HAML, first described by Ishak et al.…”

“…Preoperative diagnosis of hepatic PEComa is difficult to make ( 15 , 28 ) and is often an incidental finding ( 29 ). Other hepatic lesions, such as FNH, HCC, hemangioma, adenoma and others are more probable and hence are always put forth in diagnostic process.…”

Multimodal imaging study of hepatic perivascular epithelioid cell tumors: a case report

“…Hepatic PEComas are usually solitary, with only 5–15% occurring as part of the tuberous sclerosis complex ( 5 ). Hepatic PEComas are mainly angiomyolipomas, often characterized by a prominent epithelioid morphology and may lack mature adipose tissue or thick-walled blood vessels, typically presenting as a single phenotype ( 7 ). Therefore, it can histomorphologically mimic some hepatocyte-derived tumors, such as hepatocellular adenomas and hepatocellular carcinoma (HCC), leading to an incorrect diagnosis.…”

A Case of Primary Lymphoepithelioma-Like Carcinoma of the Bladder With Review

“…An undifferentiated nasopharyngeal carcinoma, which was characterized by epithelial neoplastic cells developing in solid or incohesive sheets mixed with a noticeable lymphoid infiltration, was first named lymphoepithelioma by Carbone in 1982 [ 9 ]. LELC had similar histological features with lymphoepithelioma but primarily occurred in other organs, such as the esophagus [ 3 ], thymus [ 4 ], lungs [ 5 ], stomach [ 6 ], and liver [ 7 ]. LELC in the urinary system is rare, most common in the bladder, followed by the renal pelvis [ 10 ], ureter [ 11 ], and urethra [ 12 ].…”

“…Lymphoepithelioma-like carcinoma (LELC) or lymphoepithelioma carcinoma is a rare malignant epithelial tumor characterized by lymphocytic interstitial hyperplasia [ 1 ]. It is most common in the nasopharynx [ 2 ], followed by the esophagus [ 3 ], thymus [ 4 ], lungs [ 5 ], stomach [ 6 ], and liver [ 7 ]. Primary LELC of the urinary system is rare.…”