title: Myxoma of the breast: report of a case with unique histological and immunohistochemical appearances.
abstract: A case of myxoma of the breast is reported. The patient, a 19 year old Japanese woman, showed a lump in the left breast which had enlarged gradually over 3 years. A tumor measuring 5 x 5 x 4.5 cm was located mainly in the mammary parenchyma, but partially involved the overlying subcutaneous tissue. Histologically the tumor was multinodular and each nodule consisted of an abundant myxoid substance with a few spindle or stellate mesenchymal cells. The presence of hyaluronic acid was observed in the myxoid area, and a few constituent cells showed immunoreactivities for S-100 protein and alpha 1-antichymotrypsin. Electron microscopic studies revealed that some constituent cells looked like undifferentiated mesenchymal cells, while others showed a differentiation similar to fibroblast or histiocyte. These findings suggest that the constituent cells might derive from totipotential primitive mesenchymal cells.
authors.affiliation: Second Department of Pathology, Hiroshima University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Arihiro
authors.forename: K
authors.initials: K
authors.lastname: Inai
authors.forename: K
authors.initials: K
authors.lastname: Kurihara
authors.forename: S
authors.initials: S
authors.lastname: Takeda
authors.forename: N
authors.initials: N
authors.lastname: Khatun
authors.forename: K
authors.initials: K
authors.lastname: Kuroi
authors.forename: H
authors.initials: H
authors.lastname: Kawami
authors.forename: T
authors.initials: T
authors.lastname: Toge
mesh_terms: D000328:Adult; D001943:Breast Neoplasms / Q000737:chemistry / Q000473:pathology*; D002454:Cell Differentiation / Q000502:physiology; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008854:Microscopy, Electron; D009232:Myxoma / Q000737:chemistry / Q000473:pathology*