title: Solitary myofibroma of the sigmoid colon: case report and review of the literature.
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.
  The virtual silde(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2096403796957687.
authors.affiliation: Departments of Pathology, Daehang Hospital, Seoul, Korea.
authors.forename: Mi-Jung
authors.initials: MJ
authors.lastname: Kim
authors.forename: Suk Hee
authors.initials: SH
authors.lastname: Lee
authors.forename: Eui Gon
authors.initials: EG
authors.lastname: Youk
authors.forename: Sojin
authors.initials: S
authors.lastname: Lee
authors.forename: Joon Hyuk
authors.initials: JH
authors.lastname: Choi
authors.forename: Kyung-Ja
authors.initials: KJ
authors.lastname: Cho
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D007889:Leiomyoma / Q000175:diagnosis* / Q000473:pathology*; D008875:Middle Aged; D047708:Myofibroma / Q000175:diagnosis* / Q000473:pathology*; D012811:Sigmoid Neoplasms / Q000175:diagnosis* / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor