Mayo Clinic, Department of Anatomic Pathology, Rochester, Minnesota 55905, USA.
Neurosurgery. 2012 Oct;71(4):E901-4. doi: 10.1227/NEU.0b013e318260ffb0.
Myoepithelioma of bone is a rare osseous tumor thought to be related to myoepithelial lesions found at other anatomic sites such as the salivary gland and skin. These tumors are composed of varying proportions of epithelial and myoepithelial cells and exhibit a spectrum of biologic behavior ranging from benign to malignant. We present the first reported case of myoepithelioma of the skull.
A 20-year-old white woman presented with a persistent right parieto-occipital skull nodule, relating its presence to a fall on the site 2 years previously. The nodule had become painful in the past 2 months. Her past medical history and workup were otherwise unremarkable. The initial biopsy was inconclusive for diagnosis. The lytic bone lesion was subsequently resected, and histopathological examination showed a proliferation of epithelioid cells in a myxochondroid background. Fluorescence in situ hybridization studies revealed a rearrangement of the EWSR1 locus. The morphologic and molecular findings were consistent with the diagnosis of myoepithelioma of bone.
Six months after surgery, the patient is doing well with no evidence of recurrence. This case illustrates the clinical presentation, histopathology, and molecular findings of a myoepithelioma of the skull with successful surgical treatment. Because myoepitheliomas with benign morphological appearance may rarely act aggressively, long-term clinical follow-up is warranted.
骨的肌上皮瘤被认为与其他解剖部位（如唾液腺和皮肤）的肌上皮病变有关，是一种罕见的骨肿瘤。这些肿瘤由不同比例的上皮细胞和肌上皮细胞组成，表现出从良性到恶性的一系列生物学行为。我们报告了首例颅骨的肌上皮瘤病例。
一名 20 岁的白人女性因 2 年前在同一部位摔倒后持续出现右顶枕部颅骨小结节而就诊，其存在与小结节有关。在过去的 2 个月中，小结节变得疼痛。她的既往病史和检查结果无其他异常。最初的活检对诊断没有定论。随后切除了溶骨性骨病变，组织病理学检查显示在黏液软骨样背景下有上皮样细胞的增殖。荧光原位杂交研究显示 EWSR1 基因座的重排。形态学和分子学发现与骨的肌上皮瘤的诊断一致。
手术后 6 个月，患者情况良好，无复发迹象。该病例说明了颅骨肌上皮瘤的临床表现、组织病理学和分子学特征，并通过成功的手术治疗得到了很好的治疗效果。由于具有良性形态学表现的肌上皮瘤可能很少具有侵袭性，因此需要进行长期的临床随访。
