Hepatic perivascular epithelioid cell tumor (PEComa): a case report with a review of literatures

Abstract

Hepatic perivascular epithelioid cell tumors (PEComas) are very rare. We report a primary hepatic PEComa with a review of the literature. A 56-year-old women presented with a nodular mass detected during the management of chronic renal failure and chronic hepatitis C. Diagnostic imaging studies suggested a nodular hepatocellular carcinoma in segment 5 of the liver. The patient underwent partial hepatectomy. A brown-colored expansile mass measuring 3.2×3.0 cm was relatively demarcated from the surrounding liver parenchyma. The tumor was mainly composed of epithelioid cells that were arranged in a trabecular growth pattern. Adipose tissue and thick-walled blood vessels were minimally identified. A small amount of extramedullary hematopoiesis was observed in the sinusoidal spaces between tumor cells. Tumor cells were diffusely immunoreactive for human melanoma black 45 (HMB45) and Melan A, focally immunoreactive for smooth muscle actin, but not for hepatocyte specific antigen (HSA).

New recognition of hepatic perivascular epithelioid cell tumours (PEComa): a retrospective analysis of 35 cases

“…According to the results of this study, hepatic PEComas were more likely to occur in the right lobe. However, combined with the ndings from other studies, as the sample size increases, the number of tumours occurring in the left lobes was approximately equal to the right [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19].…”

“…In 2013, the WHO uni ed the names of these tumours, including AMLs and PEComa-NOS. Despite the controversy, the concept of PEComa has gradually been used instead of these original names [10]. With the increasing number of reports of hepatic PEComa, physicians have gradually improved their understanding of this tumour.…”

“…A PEComa can occur in many parts of the human body, such as the uterus, skin, thorax, gastrointestinal tract and liver. The prognosis of benign hepatic PEComas, which are able to be radically cured by surgery, is usually satisfactory and little evidence of recurrence or metastasis of these tumours has been reported after surgery in previous case studies [1][2][3][4][5][6][7][8][9][10][11]. In contrast, malignant hepatic PEComas characterized by aggressive growth and early metastasis have a poor prognosis, but the incidence is much lower than benign hepatic PEComas [12].…”

“…In fact, the tumour cells also contain other cell types, including vacuolar cells with a transparent cytoplasm and eosinophilic cells with atypical nuclei. Another important feature is that abundant dilated hepatic sinusoids and extramedullary haematopoiesis have been observed in some cases [10]. Although many cases of hepatic PEComa have been reported, de nite criteria for the antidiastole on benign and malignant hepatic PEComa have not been developed.…”

Challenging liver lesions in noncirrhotic patients: Report of three cases

“…Primary liver PEComa is very rare, with slightly more than 30 cases described in the literature. 20 PEComa belongs to the same family as AML, being composed predominantly by perivascular or pericytic cells, without mature vascular, muscular, or adipose tissues. PEComas show the same diagnostic issues at radiology as AML, and the diagnosis of PEComas is even more problematic, because they are lesions of uncertain behavior.…”