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 胃肌纤维母细胞瘤

请参阅国外一篇文献（发生在乙状结肠的肌纤维瘤）

Diagn Pathol. 2013 Jun 6;8:90. doi: 10.1186/1746-1596-8-90.

Solitary myofibroma of the sigmoid colon: case report and review of the literature.

Kim MJ, Lee SH, Youk EG, Lee S, Choi JH, Cho KJ.

Source

Department of Pathology, University of Ulsan College of Medicine, Asan Medical Center, 388-1 Pungnap-dong, Seoul, Songpa-gu 138-736, Korea. kjc@amc.seoul.kr.

Abstract

A 58-year-old woman presented with a solitary myofibroma that arose in the sigmoid colon. Computed tomography revealed a highly enhanced intramural mass (1.3-cm maximum diameter) in the proximal sigmoid colon. Histologically, the tumor exhibited a biphasic growth pattern, which comprised haphazardly arranged, interwoven fascicles of plump, myoid-appearing spindle cells with elongated nuclei and abundant eosinophilic cytoplasm, and more cellular areas of primitive-appearing polygonal cells that were arranged in a hemangiopericytomatous pattern. The tumor cells were positive for smooth muscle actin (SMA), and negative for desmin, h-caldesmon, CD34, cytokeratin, S100 protein, and CD117. The Ki-67 labeling index was not high (up to 7%). Based on these histologic and immunohistochemical features, our patient was diagnosed with a myofibroma of the sigmoid colon. The presence of solitary myofibroma in the intestine of an adult requires attention to avoid misdiagnosis as a more aggressive mesenchymal tumor.

上述文献中乙状结肠肿块大体观

上述文献中，肌纤维瘤的显微镜下观。 

谢谢老师提供的经典病例，学习

上文病例的免疫组化标记结果。 

 本例发生在胃的肌纤维瘤与文献报道大肠肌纤维瘤比较，在组织学上和免疫表型上有许多相同之处，肿瘤境界都很清楚，有淡染区和深染区，梭形细胞随机排列或编织成束，有血管外皮瘤样结构，虽然血管生长的形式不完全相同。SMA都是阳性，而CD34都为阴性。