Lu Hai-zhen, Zhang Hong-tu, Liu Xiu-yun, Xue Xin-hua, Xie Yong-qiang, Liu Shang-mei, Su Qin
Department of Pathology, Chinese Academy of Medical Sciences, Beijing 100021, China.
Zhonghua Zhong Liu Za Zhi. 2009 Mar;31(3):213-6.
To study the neoplasm with perivascular epithelioid cell differentiation (PEComa) with respect to their morphologic, immunohistochemical and clinical phenotypes.
Three PEComas were included in this study, one located at the left uterine horn, and two presented as a mass in the uterine corpus. The tumors were examined by histopathology and immunohistochemistry.
The lesions were composed of spindle, blunt epithelioid cells, with foci of, or scattered, cells showing adipose differentiation in two cases. The myomelanocytic differentiation was demonstrated, proving the diagnosis as PEComa. Mild nuclear atypia and focal necrosis was observed in one lesion, and the rest two showed malignant morphologic phenotypes including moderate nuclear atypia and coagulative necrosis. The mitotic and Ki67-labelling indices ranged from 0.5/10 HPF to 14/10 HPF and 0.6% to 7.0%, respectively. All of the three patients remain alive. Malignant nature of the two lesions with worrisome morphology was confirmed by occurrence of metastases after hysterectomy.
PEComa is a rare tumor, occurring preferentially in the uterus. It is regarded as a tumor with uncertain malignant potential, but a minority of them shows malignant clinical behaviors. Some pathologic parameters including large tumor size, sheet-like necrosis, marked nuclear atypia, elevated mitotic index (> or = 10/10 HPF), aberrant mitotic figure and vascular invasion may help to establish a diagnosis of malignant PEComa.
研究具有血管周上皮样细胞分化（PEComa）的肿瘤的形态学、免疫组化及临床表型。
本研究纳入3例PEComa，1例位于子宫左角，2例表现为子宫体部肿块。对肿瘤进行组织病理学和免疫组化检查。
病变由梭形、钝圆上皮样细胞组成，2例可见灶性或散在的脂肪分化细胞。证实有肌黑素细胞分化，确诊为PEComa。1例病变观察到轻度核异型性和局灶性坏死，其余2例表现为恶性形态学表型，包括中度核异型性和凝固性坏死。有丝分裂和Ki67标记指数分别为0.5/10高倍视野至14/10高倍视野和0.6%至7.0%。3例患者均存活。子宫切除术后发生转移证实了2例形态学可疑病变的恶性性质。
PEComa是一种罕见肿瘤，好发于子宫。它被认为是一种恶性潜能不确定的肿瘤，但少数表现出恶性临床行为。一些病理参数，包括肿瘤体积大、片状坏死、明显核异型性、有丝分裂指数升高（≥10/10高倍视野）、异常有丝分裂象和血管侵犯，可能有助于诊断恶性PEComa。
