Department G.F. Ingrassia, Division of Anatomic Pathology, Policlinico-Vittorio Emanuele University Hospital, Via S. Sofia 87, Catania, Italy.
Virchows Arch. 2010 May;456(5):581-6. doi: 10.1007/s00428-010-0902-z. Epub 2010 Mar 23.
We herein report the clinical, radiological, and pathological findings of a rare case of myxoma occurring in the breast parenchyma of a 75-year-old female. The tumor was incidentally detected at a mammographic screening and, ultrasonographically, presented as an ovoid mass. Histologically, an encapsulated hypocellular, myxoid tumor with low vascularization was evident. Neoplastic cells were round- to spindle/stellate-shaped and stained with vimentin and focally with calponin. We emphasize that morphology remains preeminent in the diagnosis of a breast myxoma, while immunohistochemistry may assist in ruling out other tumor entities. Differential diagnosis with all benign and malignant myxoid lesions, primarily occurring in the breast, is provided. The histogenesis of breast myxoma is unknown. The lack of expression of desmin, alpha-smooth muscle actin, CD34, CD99, CD10, bcl-2 protein, and estrogen/progesterone/androgen receptors, all markers characteristically expressed by "the benign spindle cell tumors of the mammary stroma," would suggest that breast myxoma does not fall into this tumor category and that its putative precursor mesenchymal cell resides in the interlobular stroma.
我们在此报告一例发生于 75 岁女性乳腺实质的罕见黏液瘤的临床、影像学和病理学表现。该肿瘤是在乳腺 X 线筛查中偶然发现的，超声表现为卵圆形肿块。组织学上，可见一个包膜的低细胞性、黏液样肿瘤，血管化程度低。肿瘤细胞呈圆形至梭形/星状，免疫组化染色显示波形蛋白阳性，局灶性钙调蛋白阳性。我们强调，在乳腺黏液瘤的诊断中，形态学仍然是最重要的，而免疫组化可能有助于排除其他肿瘤实体。提供了与所有良性和恶性黏液样病变的鉴别诊断，这些病变主要发生在乳房。乳腺黏液瘤的组织发生尚不清楚。缺乏结蛋白、α-平滑肌肌动蛋白、CD34、CD99、CD10、bcl-2 蛋白和雌激素/孕激素/雄激素受体的表达，这些标志物特征性地表达于“乳腺间质良性梭形细胞肿瘤”，这表明乳腺黏液瘤不属于此类肿瘤范畴，其假定的前体细胞间叶细胞位于小叶间间质中。
