Hepatic multiple perivascular epithelioid cell neoplasm: A case report and literature review

Abstract

Abstract. Perivascular epithelioid cell neoplasm (PEComa) is a rare tumor type and primary hepatic multiple perivascular is rarer still. The present case report investigated the case of a 40-year-old woman who was admitted to The Second Xiangya Hospital for hepatic multiple tumor by physical examination without any history of abdominal pain or body weight loss. Abdominal plain computed tomography revealed three lesions in the liver. All lesions exhibited a well-defined boarder and only one mass contained fatty tissue in S6 of the liver. An enhanced scan revealed that all lesions were heterogeneous, and were enhanced on the artery phase and on portal vein phase. On delay phase, the lesions revealed continued enhancement, which is isoattenuating to the normal hepatic parenchyma. Following excision of the three masses, the patient was pathologically diagnosed with hepatic multiple PEComa. Short-term re-examination revealed no recurrence.

Computed tomography imaging features of hepatic perivascular epithelioid cell tumor

“…[ 2 ] Almost all the PEComas were identified to be strongly positive for HMB-45, SAM, and Melan-A, which are helpful for confirming the diagnosis. [ 1 – 3 ]…”

“…Computed tomography (CT) imaging typically demonstrates a heterogeneous hypo-dense mass with either well or ill-defined margin. [ 3 – 6 ] Contrast-enhanced CT in almost all hepatic PEComas shows marked enhancement in arterial phase, while mild-to-moderate enhancement in equilibrium phase. [ 7 ] The final diagnosis of PEComa is established on its histopathological characteristics, including epithelioid cells without adipocytes or abnormal blood vessels, and on immunohistochemical evidence, including positive human melanoma black 45(HMB-45), melanocytic, and smooth muscle markers.…”

PEComa—A Rare Liver Tumor

“…PEComa is more common in young women, with a 6:1 female to male ratio [6,11]. Usually, these are single lesions; however, multifocality was also reported more frequently in cases involving malignant lesions [12]. Differential diagnoses include other liver tumors, such as hepatocellular carcinoma (HCC), hemangiomas, focal nodular hyperplasia, and liver adenomas [8,13].…”

“…Similarly, both in CT and MRI, the main features of these tumors are the strong enhancement in the arterial phase and contrast wash-out in the veno-portal and delayed phases, as a consequence of rich vascularization from the branches of the hepatic artery (Figures 1-4). The presence of adipose tissue, which is easier to detect on MRI, is typical only for some PEComas, such as AMLs [12]. In addition, the tumor does not show MR-specific features; it is usually hyperintense in T2-weighted images and hypointense in T1-weighted images and may show restriction of water diffusion [6,10,15].…”

“…The basic treatment for patients with PEComa is surgery (excision o which in the case of benign tumors (and PEComa, which occurs in the m patients) is sufficient. In malignant lesions, apart from surgical treatment, t tablished post-operative therapy, chemotherapy, or radiotherapy [12,17].…”