Department of General and Transplant Surgery, Medical University of Lodz, Norbert Barlicki Memorial Teaching Hospital, Kopcinskiego Street 22, Lodz 90-153, Poland.
Surg Today. 2009;39(10):916-21. doi: 10.1007/s00595-009-3945-5. Epub 2009 Sep 27.
PEComa is very rare mesenchymal neoplasm which is formed by perivascular epithelioid cells and is characterized by dual melanocytic and myoid differentiation. Up to now only a very few cases of PEComa of the liver have been described worldwide. We herein present a patient who underwent a right hemihepatectomy for a huge tumor which could not be identified by imaging investigations. A final histopathologic examination revealed a benign epithelioid tumor with a solid growth pattern, abundant vascularity, and frequently dilated vascular channels. Immunohistochemically, the tumor cells were strongly positive for HMB-45, moderately positive for actin, and faintly positive for S-100, respectively. Based on the above findings, a diagnosis of a primary clear cell "sugar" tumor was established. Because the natural history of PEComas is mostly unpredictable, the patient has been closely followed up; however, no recurrence has so far been observed. Immunohistochemical findings play a crucial role in avoiding a misdiagnosis, and a surgical resection with an adequate margin of healthy tissue remains the gold standard of treatment. A long-term periodic follow-up is reasonable in all cases presenting with PEComa.
PEComa 是一种非常罕见的间叶性肿瘤，由血管周上皮样细胞组成，其特征为双黑色素细胞和肌源性分化。迄今为止，全世界仅描述了少数几例肝脏的 PEComa。本文报道了 1 例患者，因巨大肿瘤而接受了右半肝切除术，但影像学检查无法明确诊断。最终的组织病理学检查显示为良性上皮样肿瘤，呈实性生长模式，血管丰富，血管腔经常扩张。免疫组化染色显示，肿瘤细胞 HMB-45 强阳性，肌动蛋白中度阳性，S-100 弱阳性。根据上述发现，诊断为原发性透明细胞“糖”瘤。由于 PEComa 的自然病程大多不可预测，因此对患者进行了密切随访；然而，迄今为止尚未观察到复发。免疫组化检查结果对于避免误诊至关重要，且手术切除并保留足够的健康组织边缘仍然是治疗的金标准。所有 PEComa 患者均应进行长期定期随访。
